ivcon.c

/* ivcon.c  24 May 2001 */

/*
http://orion.math.iastate.edu/burkardt/g_src/ivcon/ivcon.html

The program can be used in command line form, as in:

ivcon input.iv output.stl
or can be used in an interactive mode, in which input and output files can be read or converted in any order.
Graphics file formats are poorly documented; hence this program was written primarily by examining typical files and struggling to interpret them. Particularly in the case of Inventor and DXF files, the program is not able to handle all the subtleties of the file format, and may mangle data, or even crash.

Helpful corrections to the 3DS reader were supplied by John F Flanagan. The GMOD reader and writer were written and supplied by Zik Saleeba. Improvements to the DXF routines to handle polygon oriented files were supplied by Zik Saleeba. The 3DS reader is based on a program by Martin van Velsen, with the help of Gert van der Spoel.

IVCON is a C version of the FORTRAN IVREAD program.
*/

/*
  Purpose:

   IVCON converts various 3D graphics files.

  Acknowledgements:

    Coding, comments, and advice were supplied by a number of collaborators.

    John F Flanagan made some corrections to the 3D Studio Max routines.

    Zik Saleeba (zik@zikzak.net) enhanced the DXF routines, and added the 
    Golgotha GMOD routines.

    Thanks to Susan M. Fisher, University of North Carolina,
    Department of Computer Science, for pointing out a coding error
    in FACE_NULL_DELETE that was overwriting all the data!

  Modified:

    04 July 2000

  Author:

    John Burkardt
*/
 
#include <ctype.h>
#include <math.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#define FALSE 0
#define TRUE 1

#define ERROR 1
#define G1_SECTION_MODEL_QUADS 18
#define G1_SECTION_MODEL_TEXTURE_NAMES 19
#define G1_SECTION_MODEL_VERT_ANIMATION 20
#define GMOD_MAX_SECTIONS 32
#define GMOD_UNUSED_VERTEX 65535
#define PI 3.141592653589793238462643
#define SUCCESS 0

#define DEG_TO_RAD   ( PI / 180.0 )
#define RAD_TO_DEG   ( 180.0 / PI )

/******************************************************************************/

/* GLOBAL DATA */

/******************************************************************************/

/*
  BACKGROUND_RGB[3], the background color.

  BYTE_SWAP, byte swapping option.

  COR3[3][COR3_MAX], the coordinates of nodes.

  COR3_MATERIAL[COR3_MAX], the index of the material of each node.

  COR3_MAX, the maximum number of points.

  COR3_NORMAL[3][COR3_MAX], normal vectors associated with nodes.

  COR3_NUM, the number of points.

  COR3_RGB[3][COR3_MAX], RGB colors associated with nodes.

  COR3_TEX_UV[2][COR3_MAX], texture coordinates associated with nodes.

  FACE[ORDER_MAX][FACE_MAX] contains the index of the I-th node making up face J.

  FACE_AREA(FACE_MAX), the area of each face.

  FACE_MATERIAL[FACE_MAX]; the material of each face.

  FACE_MAX, the maximum number of faces.

  FACE_NORMAL[3][FACE_MAX], the face normal vectors.

  FACE_NUM, the number of faces.

  FACE_ORDER[FACE_MAX], the number of vertices per face.

  FACE_TEX_UV[2][FACE_MAX], texture coordinates associated with faces.

  LINE_DEX[LINES_MAX], node indices, denoting polylines, each terminated by -1.

  LINE_MATERIAL[LINES_MAX], index into RGBCOLOR for line color.

  LINES_MAX, the maximum number of line definition items.

  LINE_NUM, the number of line definition items.

  LINE_PRUNE, pruning option ( 0 = no pruning, nonzero = pruning).

  MATERIAL_MAX, the maximum number of materials.

  MATERIAL_NUM, the number of materials.

  ORDER_MAX, the maximum number of vertices per face.

  TEXTURE_MAX, the maximum number of textures.

  TEXTURE_NAME[TEXTURE_MAX][LINE_MAX_LEN], ...

  TEXTURE_NUM, the number of textures.

  TRANSFORM_MATRIX[4][4], the current transformation matrix.

  VERTEX_MATERIAL[ORDER_MAX][FACE_MAX]; the material of vertices of faces.

  VERTEX_NORMAL[3][ORDER_MAX][FACE_MAX], normals at vertices of faces. 

  VERTEX_RGB[3][ORDER_MAX][FACE_MAX], colors of vertices of faces. 

  VERTEX_TEX_UV[2][ORDER_MAX][FACE_MAX], texture coordinates of vertices of faces.
*/

#define COLOR_MAX 1000
#define COR3_MAX 200000
#define FACE_MAX 200000
#define LINE_MAX_LEN 256
#define LEVEL_MAX 10
#define LINES_MAX 100000
#define MATERIAL_MAX 100
#define ORDER_MAX 10
#define TEXTURE_MAX 100

char   anim_name[LINE_MAX_LEN];
float  background_rgb[3];
int    bad_num;
int    byte_swap;
int    bytes_num;
int    color_num;
int    comment_num;

float  cor3[3][COR3_MAX];
int    cor3_material[COR3_MAX];
float  cor3_normal[3][COR3_MAX];
int    cor3_num;
float  cor3_tex_uv[3][COR3_MAX];

int    debug;

int    dup_num;

int    face[ORDER_MAX][FACE_MAX];
float  face_area[FACE_MAX];
int    face_flags[FACE_MAX];
int    face_material[FACE_MAX];
float  face_normal[3][FACE_MAX];
int    face_num;
int    face_object[FACE_MAX];
int    face_order[FACE_MAX];
int    face_smooth[FACE_MAX];
float  face_tex_uv[2][FACE_MAX];

char   filein_name[81];
char   fileout_name[81];

int    group_num;

int    i;
char   input[LINE_MAX_LEN];
int    k;
char   level_name[LEVEL_MAX][LINE_MAX_LEN];

int    line_dex[LINES_MAX];
int    line_material[LINES_MAX];
int    line_num;
int    line_prune;

int    list[COR3_MAX];

char   material_binding[80];
char   material_name[MATERIAL_MAX][LINE_MAX_LEN];
int    material_num;
float  material_rgba[4][MATERIAL_MAX];

char   mat_name[81];
int    max_order2;

char   normal_binding[80];
float  normal_temp[3][ORDER_MAX*FACE_MAX];

char   object_name[81];
int    object_num;

float  origin[3];
float  pivot[3];
float  rgbcolor[3][COLOR_MAX];
char   temp_name[81];

int    text_num;

char   texture_binding[80];
char   texture_name[TEXTURE_MAX][LINE_MAX_LEN];
int    texture_num;
float  texture_temp[2][ORDER_MAX*FACE_MAX];

float  transform_matrix[4][4];

int    vertex_material[ORDER_MAX][FACE_MAX];
float  vertex_normal[3][ORDER_MAX][FACE_MAX];
float  vertex_rgb[3][ORDER_MAX][FACE_MAX];
float  vertex_tex_uv[2][ORDER_MAX][FACE_MAX];

/******************************************************************************/

/* FUNCTION PROTOTYPES */

/******************************************************************************/

int                main ( int argc, char **argv );
int                ase_read ( FILE *filein );
int                ase_write ( FILE *fileout );
int                byu_read ( FILE *filein );
int                byu_write ( FILE *fileout );
int                char_index_last ( char* string, char c );
int                char_pad ( int *char_index, int *null_index, char *string, 
                     int STRING_MAX );
char               char_read ( FILE *filein );
int                char_write ( FILE *fileout, char c );
int                command_line ( char **argv );
void               cor3_normal_set ( void );
void               cor3_range ( void );
void               data_check ( void );
void               data_init ( void );
int                data_read ( void );
void               data_report ( void );
int                data_write ( void );
int                dxf_read ( FILE *filein );
int                dxf_write ( FILE *fileout );
void               edge_null_delete ( void );
void               face_area_set ( void );
void               face_normal_ave ( void );
void               face_null_delete ( void );
int                face_print ( int iface );
void               face_reverse_order ( void );
int                face_subset ( void );
void               face_to_line ( void );
void               face_to_vertex_material ( void );
char              *file_ext ( char *file_name );
float              float_read ( FILE *filein );
float              float_reverse_bytes ( float x );
int                float_write ( FILE *fileout, float float_val );
int                gmod_arch_check ( void );
int                gmod_read ( FILE *filein );
float              gmod_read_float ( FILE *filein );
unsigned short     gmod_read_w16 ( FILE *filein );
unsigned long      gmod_read_w32 ( FILE *filein );
int                gmod_write ( FILE *fileout );
void               gmod_write_float ( float Val, FILE *fileout );
void               gmod_write_w16 ( unsigned short Val, FILE *fileout );
void               gmod_write_w32 ( unsigned long Val, FILE *fileout );
void               hello ( void );
void               help ( void );
int                hrc_read ( FILE *filein );
int                hrc_write ( FILE *fileout );
void               init_program_data ( void );
int                interact ( void );
int                iv_read ( FILE *filein );
int                iv_write ( FILE *fileout );
int                ivec_max ( int n, int *a );
int                leqi ( char* string1, char* string2 );
long int           long_int_read ( FILE *filein );
int                long_int_write ( FILE *fileout, long int int_val );
void               news ( void );
void               node_to_vertex_material ( void );
int                obj_read ( FILE *filein );
int                obj_write ( FILE *fileout );
int                pov_write ( FILE *fileout );
int                rcol_find ( float a[][COR3_MAX], int m, int n, float r[] );
float              rgb_to_hue ( float r, float g, float b );
short int          short_int_read ( FILE *filein );
int                short_int_write ( FILE *fileout, short int int_val );
int                smf_read ( FILE *filein );
int                smf_write ( FILE *fileout );
int                stla_read ( FILE *filein );
int                stla_write ( FILE *fileout );
int                stlb_read ( FILE *filein );
int                stlb_write ( FILE *fileout );
void               tds_pre_process ( void );
int                tds_read ( FILE *filein );
unsigned long int  tds_read_ambient_section ( FILE *filein );
unsigned long int  tds_read_background_section ( FILE *filein );
unsigned long int  tds_read_boolean ( unsigned char *boolean, FILE *filein );
unsigned long int  tds_read_camera_section ( FILE *filein );
unsigned long int  tds_read_edit_section ( FILE *filein, int *views_read );
unsigned long int  tds_read_keyframe_section ( FILE *filein, int *views_read );
unsigned long int  tds_read_keyframe_objdes_section ( FILE *filein );
unsigned long int  tds_read_light_section ( FILE *filein );
unsigned long int  tds_read_u_long_int ( FILE *filein );
int                tds_read_long_name ( FILE *filein );
unsigned long int  tds_read_matdef_section ( FILE *filein );
unsigned long int  tds_read_material_section ( FILE *filein );
int                tds_read_name ( FILE *filein );
unsigned long int  tds_read_obj_section ( FILE *filein );
unsigned long int  tds_read_object_section ( FILE *filein );
unsigned long int  tds_read_tex_verts_section ( FILE *filein );
unsigned long int  tds_read_texmap_section ( FILE *filein );
unsigned short int tds_read_u_short_int ( FILE *filein );
unsigned long int  tds_read_spot_section ( FILE *filein );
unsigned long int  tds_read_unknown_section ( FILE *filein );
unsigned long int  tds_read_view_section ( FILE *filein, int *views_read );
unsigned long int  tds_read_vp_section ( FILE *filein, int *views_read );
int                tds_write ( FILE *fileout );
int                tds_write_string ( FILE *fileout, char *string );
int                tds_write_u_short_int ( FILE *fileout, 
                     unsigned short int int_val );
int                tec_write ( FILE *fileout );
void               tmat_init ( float a[4][4] );
void               tmat_mxm ( float a[4][4], float b[4][4], float c[4][4] );
void               tmat_mxp ( float a[4][4], float x[4], float y[4] );
void               tmat_mxp2 ( float a[4][4], float x[][3], float y[][3], int n );
void               tmat_mxv ( float a[4][4], float x[4], float y[4] );
void               tmat_rot_axis ( float a[4][4], float b[4][4], float angle, 
                     char axis );
void               tmat_rot_vector ( float a[4][4], float b[4][4], float angle, 
                     float v1, float v2, float v3 );
void               tmat_scale ( float a[4][4], float b[4][4], float sx, float sy, 
                     float sz );
void               tmat_shear ( float a[4][4], float b[4][4], char *axis, 
                     float s );
void               tmat_trans ( float a[4][4], float b[4][4], float x, float y, 
                     float z );
int                tria_read ( FILE *filein );
int                tria_write ( FILE *fileout );
int                trib_read ( FILE *filein );
int                trib_write ( FILE *fileout );
int                txt_write ( FILE *fileout );
int                ucd_write ( FILE *fileout );
void               vertex_normal_set ( void );
void               vertex_to_face_material ( void );
void               vertex_to_node_material ( void );
int                vla_read ( FILE *filein );
int                vla_write ( FILE *fileout );
int                wrl_write ( FILE *filout );
int                xgl_write ( FILE *fileout );

/******************************************************************************/

int main ( int argc, char **argv )

/******************************************************************************/

/*
  Purpose:

    MAIN is the main program for converting graphics files.

  Modified:

    26 May 1999

  Author:
 
    John Burkardt
*/
{
  int result;
/*
  Initialize the program data.
*/
  init_program_data ( );
/*
  If there are at least two command line arguments, call COMMAND_LINE.
  Otherwise call INTERACT and get information from the user.
*/ 
  if ( argc >= 2 ) {
    result = command_line ( argv );
  }
  else {
    result = interact (  );
  }

  return result;
}
/******************************************************************************/

int ase_read ( FILE *filein )

/******************************************************************************/

/*
  Purpose:
   
    ASE_READ reads an AutoCAD ASE file.

  Modified:

    22 May 1999

  Author:

    John Burkardt
*/
{
  float bval;
  int   count;
  float gval;
  int   i;
  int   iface;
  int   ivert;
  int   iword;
  int   level;
  char *next;
  int   nlbrack;
  int   nrbrack;
  int   cor3_num_old;
  int   face_num_old;
  float rval;
  float temp;
  int   width;
  char  word[LINE_MAX_LEN];
  char  word1[LINE_MAX_LEN];
  char  word2[LINE_MAX_LEN];
  char  wordm1[LINE_MAX_LEN];
  float x;
  float y;
  float z;

  level = 0;
  strcpy ( level_name[0], "Top" );
  cor3_num_old = cor3_num;
  face_num_old = face_num;
  nlbrack = 0;
  nrbrack = 0;

  strcpy ( word, " " );
  strcpy ( wordm1, " " );
/*
  Read a line of text from the file.
*/

  for ( ;; ) {

    if ( fgets ( input, LINE_MAX_LEN, filein ) == NULL ) {
      break;
    }

    text_num = text_num + 1;
    next = input;
    iword = 0;
/*
  Read the next word from the line.
*/
    for ( ;; ) {

      strcpy ( wordm1, word );
      strcpy ( word, " " );

      count = sscanf ( next, "%s%n", word, &width );
      next = next + width;

      if ( count <= 0 ) {
        break;
      }

      iword = iword + 1;

      if ( iword == 1 ) {
        strcpy ( word1, word );
      }
/*
  In case the new word is a bracket, update the bracket count.
*/
      if ( strcmp ( word, "{" ) == 0 ) {

        nlbrack = nlbrack + 1;
        level = nlbrack - nrbrack;
        strcpy ( level_name[level], wordm1 );
      }
      else if ( strcmp ( word, "}" ) == 0 ) {

        nrbrack = nrbrack + 1;

        if ( nlbrack < nrbrack ) {

          printf ( "\n" );
          printf ( "ASE_READ - Fatal error!\n" );
          printf ( "  Extraneous right bracket on line %d\n", text_num );
          printf ( "  Currently processing field:\n" );
          printf ( "%s\n", level_name[level] );
          return ERROR;
        }

      }
/*
  *3DSMAX_ASCIIEXPORT  200
*/
      if ( strcmp ( word1, "*3DSMAX_ASCIIEXPORT" ) == 0 ) {
        break;
      }
/*
  *COMMENT
*/
      else if ( strcmp ( word1, "*COMMENT" ) == 0 ) {
        break;
      }
/*
  *GEOMOBJECT
*/
      else if ( strcmp ( level_name[level], "*GEOMOBJECT" ) == 0 ) {

        if ( strcmp ( word, "{" ) == 0 ) {
          continue;
        }
        else if ( strcmp ( word, "}" ) == 0 ) {
          level = nlbrack - nrbrack;
          continue;
        }
/*
  Why don't you read and save this name?
*/
        else if ( strcmp ( word, "*NODE_NAME" ) == 0 ) {
          break;
        }
        else if ( strcmp ( word, "*NODE_TM" ) == 0 ) {
          continue;
        }
        else if ( strcmp ( word, "*MESH" ) == 0 ) {
          continue;
        }
        else if ( strcmp ( word, "*PROP_CASTSHADOW" ) == 0 ) {
          break;
        }
        else if ( strcmp ( word, "*PROP_MOTIONBLUR" ) == 0 ) {
          break;
        }
        else if ( strcmp ( word, "*PROP_RECVSHADOW" ) == 0 ) {
          break;
        }
        else {
          bad_num = bad_num + 1;
          printf ( "Bad data in GEOMOBJECT, line %d\n", text_num );
          break;
        }
      }
/*
  *MESH
*/
      else if ( strcmp ( level_name[level], "*MESH" ) == 0 ) {

        if ( strcmp ( word, "{" ) == 0 ) {
          continue;
        }
        else if ( strcmp ( word, "}" ) == 0 ) {
          level = nlbrack - nrbrack;
          continue;
        }
        else if ( strcmp ( word, "*MESH_CFACELIST" ) == 0 ) {
          continue;
        }
        else if ( strcmp ( word, "*MESH_CVERTLIST" ) == 0 ) {
          continue;
        }
        else if ( strcmp ( word, "*MESH_FACE_LIST" ) == 0 ) {
          continue;
        }
        else if ( strcmp ( word, "*MESH_NORMALS" ) == 0 ) {
          continue;
        }
        else if ( strcmp ( word, "*MESH_NUMCVERTEX" ) == 0 ) {
          break;
        }
        else if ( strcmp ( word, "*MESH_NUMCVFACES" ) == 0 ) {
          break;
        }
        else if ( strcmp ( word, "*MESH_NUMFACES" ) == 0 ) {
          break;
        }
        else if ( strcmp ( word, "*MESH_NUMTVERTEX" ) == 0 ) {
          break;
        }
        else if ( strcmp ( word, "*MESH_NUMTVFACES" ) == 0 ) {
          break;
        }
        else if ( strcmp ( word, "*MESH_NUMVERTEX" ) == 0 ) {
          break;
        }
        else if ( strcmp ( word, "*MESH_TFACELIST" ) == 0 ) {
          continue;
        }
        else if ( strcmp ( word, "*MESH_TVERTLIST" ) == 0 ) {
          continue;
        }
        else if ( strcmp ( word, "*MESH_VERTEX_LIST" ) == 0 ) {
          continue;
        }
        else if ( strcmp ( word, "*TIMEVALUE" ) == 0 ) {
          break;
        }
        else {
          bad_num = bad_num + 1;
          printf ( "Bad data in MESH, line %d\n", text_num );
          break;
        }
      }
/*
  *MESH_CFACELIST
*/
      else if ( strcmp ( level_name[level], "*MESH_CFACELIST" ) == 0 ) {

        if ( strcmp ( word, "{" ) == 0 ) {
          continue;
        }
        else if ( strcmp ( word, "}" ) == 0 ) {
          level = nlbrack - nrbrack;
          continue;
        }
        else if ( strcmp ( word, "*MESH_CFACE" ) == 0 ) {
          break;
        }
        else {
          bad_num = bad_num + 1;
          printf ( "Bad data in MESH_CFACE, line %d\n", text_num );
          break;
        }
      }
/*
  *MESH_CVERTLIST

  Mesh vertex indices must be incremented by COR3_NUM_OLD before being stored
  in the internal array.
*/
      else if ( strcmp ( level_name[level], "*MESH_CVERTLIST" ) == 0 ) {

        if ( strcmp ( word, "{" ) == 0 ) {
          continue;
        }
        else if ( strcmp ( word, "}" ) == 0 ) {
          level = nlbrack - nrbrack;
          continue;
        }
        else if ( strcmp ( word, "*MESH_VERTCOL" ) == 0 ) {

          count = sscanf ( next, "%d%n", &i, &width );
          next = next + width;

          i = i + cor3_num_old;

          count = sscanf ( next, "%f%n", &rval, &width );
          next = next + width;

          count = sscanf ( next, "%f%n", &gval, &width );
          next = next + width;

          count = sscanf ( next, "%f%n", &bval, &width );
          next = next + width;

          if ( material_num < MATERIAL_MAX ) {
            material_rgba[0][material_num] = rval;
            material_rgba[1][material_num] = gval;
            material_rgba[2][material_num] = bval;
            material_rgba[3][material_num] = 1.0;
          }

          material_num = material_num + 1;
          cor3_material[i] = material_num;
        }
        else {
          bad_num = bad_num + 1;
          printf ( "\n" );
          printf ( "ASE_READ - Warning!\n" );
          printf ( "  Bad data in MESH_CVERTLIST, line %d\n", text_num );
          break;
        }

      }
/*
  *MESH_FACE_LIST
  This coding assumes a face is always triangular or quadrilateral.
*/
      else if ( strcmp ( level_name[level], "*MESH_FACE_LIST" ) == 0 ) {

        if ( strcmp ( word, "{" ) == 0 ) {
          continue;
        }
        else if ( strcmp ( word, "}" ) == 0 ) {
          level = nlbrack - nrbrack;
          continue;
        }
        else if ( strcmp ( word, "*MESH_FACE" ) == 0 ) {

          if ( face_num < FACE_MAX ) {

            face_material[face_num] = 0;
            face_order[face_num] = 0;

            count = sscanf ( next, "%d%n", &i, &width );
            next = next + width;

            count = sscanf ( next, "%s%n", word2, &width );
            next = next + width;
            count = sscanf ( next, "%s%n", word2, &width );
            next = next + width;

            count = sscanf ( next, "%d%n", &i, &width );
            next = next + width;
            face[0][face_num] = i + cor3_num_old;
            face_order[face_num] = face_order[face_num] + 1;

            count = sscanf ( next, "%s%n", word2, &width );
            next = next + width;

            count = sscanf ( next, "%d%n", &i, &width );
            next = next + width;
            face[1][face_num] = i + cor3_num_old;
            face_order[face_num] = face_order[face_num] + 1;

            count = sscanf ( next, "%s%n", word2, &width );
            next = next + width;

            count = sscanf ( next, "%d%n", &i, &width );
            next = next + width;
            face[2][face_num] = i + cor3_num_old;
            face_order[face_num] = face_order[face_num] + 1;

            count = sscanf ( next, "%s%n", word2, &width );
            next = next + width;

            if ( strcmp ( word2, "D:" ) == 0 ) {
              count = sscanf ( next, "%d%n", &i, &width );
              next = next + width;
              face[3][face_num] = i + cor3_num_old;
              face_order[face_num] = face_order[face_num] + 1;
            }
          }

          face_num = face_num + 1;

          break;

        }
        else {
          bad_num = bad_num + 1;
          printf ( "Bad data in MESH_FACE_LIST, line %d\n", text_num );
          break;
        }
      }
/*
  *MESH_NORMALS
*/
      else if ( strcmp ( level_name[level], "*MESH_NORMALS" ) == 0 ) {

        if ( strcmp ( word, "{" ) == 0 ) {
          continue;
        }
        else if ( strcmp ( word, "}" ) == 0 ) {
          level = nlbrack - nrbrack;
          continue;
        }
        else if ( strcmp ( word, "*MESH_FACENORMAL" ) == 0 ) {

          count = sscanf ( next, "%d%n", &iface, &width );
          next = next + width;

          count = sscanf ( next, "%f%n", &x, &width );
          next = next + width;

          count = sscanf ( next, "%f%n", &y, &width );
          next = next + width;

          count = sscanf ( next, "%f%n", &z, &width );
          next = next + width;

          iface = iface + face_num_old;
          ivert = 0;

          face_normal[0][iface] = x;
          face_normal[1][iface] = y;
          face_normal[2][iface] = z;

          break;

        }
        else if ( strcmp ( word, "*MESH_VERTEXNORMAL" ) == 0 ) {

          count = sscanf ( next, "%d%n", &i, &width );
          next = next + width;

          count = sscanf ( next, "%f%n", &x, &width );
          next = next + width;

          count = sscanf ( next, "%f%n", &y, &width );
          next = next + width;

          count = sscanf ( next, "%f%n", &z, &width );
          next = next + width;

          vertex_normal[0][ivert][iface] = x;
          vertex_normal[1][ivert][iface] = y;
          vertex_normal[2][ivert][iface] = z;
          ivert = ivert + 1;

          break;
        }
        else {
          bad_num = bad_num + 1;
          printf ( "Bad data in MESH_NORMALS, line %d\n", text_num );
          break;
        }
      }
/*
  *MESH_TFACELIST
*/
      else if ( strcmp ( level_name[level], "*MESH_TFACELIST" ) == 0 ) {

        if ( strcmp ( word, "{" ) == 0 ) {
          continue;
        }
        else if ( strcmp ( word, "}" ) == 0 ) {
          level = nlbrack - nrbrack;
          continue;
        }
        else if ( strcmp ( word1, "*MESH_TFACE" ) == 0 ) {
          break;
        }
        else {
          bad_num = bad_num + 1;
          printf ( "Bad data in MESH_TFACE_LIST, line %d\n", text_num );
          break;
        }
      }
/*
  *MESH_TVERTLIST
*/
      else if ( strcmp ( level_name[level], "*MESH_TVERTLIST" ) == 0 ) {

        if ( strcmp ( word, "{" ) == 0 ) {
          continue;
        }
        else if ( strcmp ( word, "}" ) == 0 ) {
          level = nlbrack - nrbrack;
          continue;
        }
        else if ( strcmp ( word1, "*MESH_TVERT" ) == 0  ) {
          break;
        }
        else {
          bad_num = bad_num + 1;
          printf ( "Bad data in MESH_TVERTLIST, line %d\n", text_num );
          break;
        }
      }
/*
  *MESH_VERTEX_LIST
*/
      else if ( strcmp ( level_name[level], "*MESH_VERTEX_LIST" ) == 0 ) {

        if ( strcmp ( word, "{" ) == 0 ) {
          cor3_num_old = cor3_num;
          continue;
        }
        else if ( strcmp ( word, "}" ) == 0 ) {
          level = nlbrack - nrbrack;
          continue;
        }
        else if ( strcmp ( word1, "*MESH_VERTEX" ) == 0 ) {

          count = sscanf ( next, "%d%n", &i, &width );
          next = next + width;

          count = sscanf ( next, "%f%n", &x, &width );
          next = next + width;

          count = sscanf ( next, "%f%n", &y, &width );
          next = next + width;

          count = sscanf ( next, "%f%n", &z, &width );
          next = next + width;

          i = i + cor3_num_old;
          if ( cor3_num < i + 1 ) {
            cor3_num = i + 1;
          }

          if ( i < COR3_MAX ) {

            cor3[0][i] =
              transform_matrix[0][0] * x 
            + transform_matrix[0][1] * y 
            + transform_matrix[0][2] * z 
            + transform_matrix[0][3];

            cor3[1][i] =
              transform_matrix[1][0] * x 
            + transform_matrix[1][1] * y 
            + transform_matrix[1][2] * z 
            + transform_matrix[1][3];

            cor3[2][i] =
              transform_matrix[2][0] * x 
            + transform_matrix[2][1] * y 
            + transform_matrix[2][2] * z 
            + transform_matrix[2][3];
          }

          break;
        }
        else {
          bad_num = bad_num + 1;
          printf ( "Bad data in MESH_VERTEX_LIST, line %d\n", text_num );
          break;
        }
      }
/*
  *NODE_TM

  Each node should start out with a default transformation matrix.
*/
      else if ( strcmp ( level_name[level], "*NODE_TM" ) == 0 ) {

        if ( strcmp ( word, "{" ) == 0 ) {

          tmat_init ( transform_matrix );

          continue;
        }
        else if ( strcmp ( word, "}" ) == 0 ) {
          level = nlbrack - nrbrack;
          continue;
        }
        else if ( strcmp ( word, "*INHERIT_POS" ) == 0 ) {
          break;
        }
        else if ( strcmp ( word, "*INHERIT_ROT" ) == 0 ) {
          break;
        }
        else if ( strcmp ( word, "*INHERIT_SCL" ) == 0 ) {
          break;
        }
        else if ( strcmp ( word, "*NODE_NAME" ) == 0 ) {
          break;
        }
        else if ( strcmp ( word, "*TM_POS" ) == 0 ) {
          break;
        }
        else if ( strcmp ( word, "*TM_ROTANGLE" ) == 0 ) {
          break;
        }
        else if ( strcmp ( word, "*TM_ROTAXIS" ) == 0 ) {
          break;
        }
        else if ( strcmp ( word, "*TM_ROW0" ) == 0 ) {

          count = sscanf ( next, "%f%n", &temp, &width );
          next = next + width;
          transform_matrix[0][0] = temp;

          count = sscanf ( next, "%f%n", &temp, &width );
          next = next + width;
          transform_matrix[1][0] = temp;

          count = sscanf ( next, "%f%n", &temp, &width );
          next = next + width;
          transform_matrix[2][0] = temp;

          break;
        }
        else if ( strcmp ( word, "*TM_ROW1" ) == 0 ) {

          count = sscanf ( next, "%f%n", &temp, &width );
          next = next + width;
          transform_matrix[0][1] = temp;

          count = sscanf ( next, "%f%n", &temp, &width );
          next = next + width;
          transform_matrix[1][1] = temp;

          count = sscanf ( next, "%f%n", &temp, &width );
          next = next + width;
          transform_matrix[2][1] = temp;

          break;
        }
        else if ( strcmp ( word, "*TM_ROW2" ) == 0 ) {

          count = sscanf ( next, "%f%n", &temp, &width );
          next = next + width;
          transform_matrix[0][2] = temp;

          count = sscanf ( next, "%f%n", &temp, &width );
          next = next + width;
          transform_matrix[1][2] = temp;

          count = sscanf ( next, "%f%n", &temp, &width );
          next = next + width;
          transform_matrix[2][2] = temp;

          break;
        }
        else if ( strcmp ( word, "*TM_ROW3" ) == 0 ) {

          count = sscanf ( next, "%f%n", &temp, &width );
          next = next + width;
          transform_matrix[0][3] = temp;

          count = sscanf ( next, "%f%n", &temp, &width );
          next = next + width;
          transform_matrix[1][3] = temp;

          count = sscanf ( next, "%f%n", &temp, &width );
          next = next + width;
          transform_matrix[2][3] = temp;

          break;
        }
        else if ( strcmp ( word, "*TM_SCALE" ) == 0 ) {
          break;
        }
        else if ( strcmp ( word, "*TM_SCALEAXIS" ) == 0 ) {
          break;
        }
        else if ( strcmp ( word, "*TM_SCALEAXISANG" ) == 0 ) {
          break;
        }
        else {
          bad_num = bad_num + 1;
          printf ( "Bad data in NODE_TM, line %d\n", text_num );
          break;
        }
      }
/*
  *SCENE
*/
      else if ( strcmp ( level_name[level], "*SCENE" ) == 0 ) {

        if ( strcmp ( word, "{" ) == 0 ) {
          continue;
        }
        else if ( strcmp ( word, "}" ) == 0 ) {
          level = nlbrack - nrbrack;
          continue;
        }
        else if ( strcmp ( word, "*SCENE_AMBIENT_STATIC" ) == 0 ) {
          break;
        }
        else if ( strcmp ( word, "*SCENE_BACKGROUND_STATIC" ) == 0 ) {
          break;
        }
        else if ( strcmp ( word, "*SCENE_FILENAME" ) == 0 ) {
          break;
        }
        else if ( strcmp ( word, "*SCENE_FIRSTFRAME" ) == 0 ) {
          break;
        }
        else if ( strcmp ( word, "*SCENE_FRAMESPEED" ) == 0 ) {
          break;
        }
        else if ( strcmp ( word, "*SCENE_LASTFRAME" ) == 0 ) {
          break;
        }
        else if ( strcmp ( word, "*SCENE_TICKSPERFRAME" ) == 0 ) {
          break;
        }
        else {
          bad_num = bad_num + 1;
          printf ( "Bad data in SCENE, line %d\n", text_num );
          break;
        }

      }

    }
/*
  End of loop reading words from the line.
*/
  }
/*
  End of loop reading lines from input file.
*/

  return SUCCESS;
}
/******************************************************************************/

int ase_write ( FILE *fileout )

/******************************************************************************/

/*
  Purpose:

    ASE_WRITE writes graphics information to an AutoCAD ASE file.

  Modified:

    30 September 1998

  Author:

    John Burkardt

*/
{
  int i1;
  int i2;
  int i3;
  int i4;
  int iface;
  int ivert;
  int j;
  int text_num;

  text_num = 0;
/*
  Write the header.
*/
  fprintf ( fileout, "*3DSMAX_ASCIIEXPORT 200\n" );
  fprintf ( fileout, "*COMMENT \"%s, created by IVCON.\"\n", fileout_name );
  fprintf ( fileout, "*COMMENT \"Original data in %s\"\n", filein_name );

  text_num = text_num + 3;
/*
  Write the scene block.
*/
  fprintf ( fileout, "*SCENE {\n" );
  fprintf ( fileout, "  *SCENE_FILENAME \"\"\n" );
  fprintf ( fileout, "  *SCENE_FIRSTFRAME 0\n" );
  fprintf ( fileout, "  *SCENE_LASTFRAME 100\n" );
  fprintf ( fileout, "  *SCENE_FRAMESPEED 30\n" );
  fprintf ( fileout, "  *SCENE_TICKSPERFRAME 160\n" );
  fprintf ( fileout, "  *SCENE_BACKGROUND_STATIC 0.0000 0.0000 0.0000\n" );
  fprintf ( fileout, "  *SCENE_AMBIENT_STATIC 0.0431 0.0431 0.0431\n" );
  fprintf ( fileout, "}\n" );

  text_num = text_num + 9;
/*
  Begin the big geometry block.
*/
  fprintf ( fileout, "*GEOMOBJECT {\n" );
  fprintf ( fileout, "  *NODE_NAME \"%s\"\n", object_name );

  text_num = text_num + 2;
/*
  Sub block NODE_TM:
*/
  fprintf ( fileout, "  *NODE_TM {\n" );
  fprintf ( fileout, "    *NODE_NAME \"Object01\"\n" );
  fprintf ( fileout, "    *INHERIT_POS 0 0 0\n" );
  fprintf ( fileout, "    *INHERIT_ROT 0 0 0\n" );
  fprintf ( fileout, "    *INHERIT_SCL 0 0 0\n" );
  fprintf ( fileout, "    *TM_ROW0 1.0000 0.0000 0.0000\n" );
  fprintf ( fileout, "    *TM_ROW1 0.0000 1.0000 0.0000\n" );
  fprintf ( fileout, "    *TM_ROW2 0.0000 0.0000 1.0000\n" );
  fprintf ( fileout, "    *TM_ROW3 0.0000 0.0000 0.0000\n" );
  fprintf ( fileout, "    *TM_POS 0.0000 0.0000 0.0000\n" );
  fprintf ( fileout, "    *TM_ROTAXIS 0.0000 0.0000 0.0000\n" );
  fprintf ( fileout, "    *TM_ROTANGLE 0.0000\n" );
  fprintf ( fileout, "    *TM_SCALE 1.0000 1.0000 1.0000\n" );
  fprintf ( fileout, "    *TM_SCALEAXIS 0.0000 0.0000 0.0000\n" );
  fprintf ( fileout, "    *TM_SCALEAXISANG 0.0000\n" );
  fprintf ( fileout, "  }\n" );

  text_num = text_num + 16;
/*
  Sub block MESH:
    Items
*/
  fprintf ( fileout, "  *MESH {\n" );
  fprintf ( fileout, "    *TIMEVALUE 0\n" );
  fprintf ( fileout, "    *MESH_NUMVERTEX %d\n", cor3_num );
  fprintf ( fileout, "    *MESH_NUMFACES %d\n", face_num );

  text_num = text_num + 4;
/*
  Sub sub block MESH_VERTEX_LIST
*/
  fprintf ( fileout, "    *MESH_VERTEX_LIST {\n" );
  text_num = text_num + 1;

  for ( j = 0; j < cor3_num; j++ ) {
    fprintf ( fileout, "      *MESH_VERTEX %d %f %f %f\n", j, cor3[0][j],
      cor3[1][j], cor3[2][j] );
    text_num = text_num + 1;
  }

  fprintf ( fileout, "    }\n" );
  text_num = text_num + 1;
/*
  Sub sub block MESH_FACE_LIST
    Items MESH_FACE
*/
  fprintf ( fileout, "    *MESH_FACE_LIST {\n" );
  text_num = text_num + 1;

  for ( iface = 0; iface < face_num; iface++ ) {

    i1 = face[0][iface];
    i2 = face[1][iface];
    i3 = face[2][iface];

    if ( face_order[iface] == 3 ) {
      fprintf ( fileout, "      *MESH_FACE %d: A: %d B: %d C: %d", iface, i1, i2, i3 ); 
      fprintf ( fileout, " AB: 1 BC: 1 CA: 1 *MESH_SMOOTHING *MESH_MTLID 1\n" );
      text_num = text_num + 1;
    }
    else if ( face_order[iface] == 4 ) {
      i4 = face[3][iface];
      fprintf ( fileout, "      *MESH_FACE %d: A: %d B: %d C: %d D: %d", iface, i1, i2, i3, i4 ); 
      fprintf ( fileout, " AB: 1 BC: 1 CD: 1 DA: 1 *MESH_SMOOTHING *MESH_MTLID 1\n" );
      text_num = text_num + 1;
    }
  }

  fprintf ( fileout, "    }\n" );
  text_num = text_num + 1;
/*
  Item MESH_NUMTVERTEX.
*/
  fprintf ( fileout, "    *MESH_NUMTVERTEX 0\n" );
  text_num = text_num + 1;
/*
  Item NUMCVERTEX.
*/
  fprintf ( fileout, "    *MESH_NUMCVERTEX 0\n" );
  text_num = text_num + 1;
/*
  Sub block MESH_NORMALS
    Items MESH_FACENORMAL, MESH_VERTEXNORMAL (repeated)
*/
  fprintf ( fileout, "    *MESH_NORMALS {\n" );
  text_num = text_num + 1;

  for ( iface = 0; iface < face_num; iface++ ) {

    fprintf ( fileout, "      *MESH_FACENORMAL %d %f %f %f\n", 
      iface, face_normal[0][iface], face_normal[1][iface], face_normal[2][iface] );
    text_num = text_num + 1;

    for ( ivert = 0; ivert < face_order[iface]; ivert++ ) {
      fprintf ( fileout, "      *MESH_VERTEXNORMAL %d %f %f %f\n", 
        face[ivert][iface], vertex_normal[0][ivert][iface], 
        vertex_normal[1][ivert][iface], vertex_normal[2][ivert][iface] );
      text_num = text_num + 1;
    }
  }

  fprintf ( fileout, "    }\n" );
  text_num = text_num + 1;
/*
  Close the MESH object.
*/
  fprintf ( fileout, "  }\n" );
/*
  A few closing parameters.
*/
  fprintf ( fileout, "  *PROP_MOTIONBLUR 0\n" );
  fprintf ( fileout, "  *PROP_CASTSHADOW 1\n" );
  fprintf ( fileout, "  *PROP_RECVSHADOW 1\n" );
/*
  Close the GEOM object.
*/
  fprintf ( fileout, "}\n" );

  text_num = text_num + 5;
/*
  Report.
*/
  printf ( "\n" );
  printf ( "ASE_WRITE - Wrote %d text lines;\n", text_num );

  return SUCCESS;
}
/**********************************************************************/

int byu_read ( FILE *filein )

/**********************************************************************/

/*
  Purpose:

    BYU_READ reads graphics data from a Movie.BYU surface geometry file.

  Discussion:

    A Movie.BYU surface geometry file contains 4 groups of data.

    The first group of data is a single line, containing 4 integers,
    each one left justified in 8 columns.  The integers are:

      PART_NUM, VERTEX_NUM, POLY_NUM, EDGE_NUM,
 
    that is, the number of parts or objects, the number of vertices or nodes,
    the number of polygons or faces, and the number of edges.

    The second group of data is a single line, containing 2 integers,
    each one left justified in 8 columnes.  The integers are:

      POLY1, POLY2,

    the starting and ending polygon numbers.  Presumably, this means
    that the polygons are labeled POLY1, POLY1+1, ..., POLY2, comprising
    a total of POLY_NUM polygons.

    The third group is the X, Y and Z coordinates of all the vertices.
    These may be written using a FORTRAN format of 6E12.5, which
    crams two sets of (X,Y,Z) data onto each line, with each real value
    written in an exponential format with 5 places after the decimal.
    However, it is generally possible to write the XYZ coordinate data
    for each vertex on a separate line.

    The fourth group defines the polygons in terms of the vertex indices.
    For each polygon, the vertices that make up the polygon are listed in
    counterclockwise order.  The last vertex listed is given with a negative
    sign to indicate the end of the list.  All the vertices for all the
    polygons are listed one after the other, using a format that puts
    up to 10 left-justified integers on a line, with each integer occupying
    8 spaces.

    This code will certainly read a BYU file created by BYU_WRITE, but
    it will not handle more general files.  In particular, an object
    can have several parts, the coordinate data can be grouped so
    that there are 2 sets of (x,y,z) data per line, and so on.

  Example:

      1       8       6      24
      1       6
    0.00000E+00 0.00000E+00 0.00000E+00
    1.00000E+00 0.00000E+00 0.00000E+00
    1.00000E+00 2.00000E+00 0.00000E+00
    0.00000E+00 2.00000E+00 0.00000E+00
    0.00000E+00 0.00000E+00 1.00000E+00
    1.00000E+00 0.00000E+00 1.00000E+00
    1.00000E+00 2.00000E+00 1.00000E+00
    0.00000E+00 2.00000E+00 1.00000E+00
      4       3       2      -1
      5       6       7      -8
      1       5       8      -4
      4       8       7      -3
      3       7       6      -2
      2       6       5      -1

  Modified:

    24 May 2001

  Author:

    John Burkardt

*/
{
  int cor3_num_new;
  int count;
  int edge_num;
  int face_num_new;
  int iface;
  int ival;
  int ivert;
  int j;
  char *next;
  int part_num;
  int poly1;
  int poly2;
  int text_num;
  int width;
  float x;
  float y;
  float z;

  text_num = 0;

  if ( fgets ( input, LINE_MAX_LEN, filein ) == NULL ) {
    return ERROR;
  }
  text_num = text_num + 1;

  sscanf ( input, "%d %d %d %d", &part_num, &cor3_num_new, &face_num_new,
    &edge_num );

  if ( fgets ( input, LINE_MAX_LEN, filein ) == NULL ) {
    return ERROR;
  }
  text_num = text_num + 1;

  sscanf ( input, "%d %d", &poly1, &poly2 );

  for ( j = cor3_num; j < cor3_num + cor3_num_new; j++ ) {

    if ( fgets ( input, LINE_MAX_LEN, filein ) == NULL ) {
      return ERROR;
    }
    text_num = text_num + 1;

    sscanf ( input, "%f %f %f", &x, &y, &z );
    cor3[0][j] = x;
    cor3[1][j] = y;
    cor3[2][j] = z;
  }

  for ( iface = face_num; iface < face_num + face_num_new; iface++ ) {

    if ( fgets ( input, LINE_MAX_LEN, filein ) == NULL ) {
      return ERROR;
    }
    text_num = text_num + 1;

    next = input;
    ivert = 0;

    for (;;) {

      count = sscanf ( next, "%d%n", &ival, &width );
      next = next + width;

      if ( count <= 0 ) {
        return ERROR;
      }

      if ( ival > 0 ) {
        face[ivert][iface] = ival - 1 + cor3_num;
      }
      else {
        face[ivert][iface] = - ival - 1 - cor3_num;
        break;
      }

      ivert = ivert + 1;

    }
    face_order[iface] = ivert + 1;
  }

  cor3_num = cor3_num + cor3_num_new;
  face_num = face_num + face_num_new;
/*
  Report.
*/
  printf ( "\n" );
  printf ( "BYU_READ - Read %d text lines.\n", text_num );

  return SUCCESS;
}
/**********************************************************************/

int byu_write ( FILE *fileout )

/**********************************************************************/

/*
  Purpose:

    BYU_WRITE writes out the graphics data as a Movie.BYU surface geometry file.

  Discussion:

    A Movie.BYU surface geometry file contains 4 groups of data.

    The first group of data is a single line, containing 4 integers,
    each one left justified in 8 columns.  The integers are:

      PART_NUM, VERTEX_NUM, POLY_NUM, EDGE_NUM,
 
    that is, the number of parts or objects, the number of vertices or nodes,
    the number of polygons or faces, and the number of edges.

    The second group of data is a single line, containing 2 integers,
    each one left justified in 8 columnes.  The integers are:

      POLY1, POLY2,

    the starting and ending polygon numbers.  Presumably, this means
    that the polygons are labeled POLY1, POLY1+1, ..., POLY2, comprising
    a total of POLY_NUM polygons.

    The third group is the X, Y and Z coordinates of all the vertices.
    These may be written using a FORTRAN format of 6E12.5, which
    crams two sets of (X,Y,Z) data onto each line, with each real value
    written in an exponential format with 5 places after the decimal.
    However, it is generally possible to write the XYZ coordinate data
    for each vertex on a separate line.

    The fourth group defines the polygons in terms of the vertex indices.
    For each polygon, the vertices that make up the polygon are listed in
    counterclockwise order.  The last vertex listed is given with a negative
    sign to indicate the end of the list.  All the vertices for all the
    polygons are listed one after the other, using a format that puts
    up to 10 left-justified integers on a line, with each integer occupying
    8 spaces.

  Example:

      1       8       6      24
      1       6
    0.00000E+00 0.00000E+00 0.00000E+00
    1.00000E+00 0.00000E+00 0.00000E+00
    1.00000E+00 2.00000E+00 0.00000E+00
    0.00000E+00 2.00000E+00 0.00000E+00
    0.00000E+00 0.00000E+00 1.00000E+00
    1.00000E+00 0.00000E+00 1.00000E+00
    1.00000E+00 2.00000E+00 1.00000E+00
    0.00000E+00 2.00000E+00 1.00000E+00
      4       3       2      -1
      5       6       7      -8
      1       5       8      -4
      4       8       7      -3
      3       7       6      -2
      2       6       5      -1

  Modified:

    24 May 2001

  Author:

    John Burkardt
*/
{
  int edge_num;
  int iface;
  int ivert;
  int j;
  int jp;
  int part_num;
  int text_num;

  text_num = 0;

  edge_num = 0;
  for ( iface = 0; iface < face_num; iface++ ) {
    edge_num = edge_num + face_order[iface];
  }

  part_num = 1;

  fprintf ( fileout, "%d %d %d %d\n", part_num, cor3_num, face_num, edge_num );
  text_num = text_num + 1;

  fprintf ( fileout, "1 %d\n", face_num );
  text_num = text_num + 1;

  for ( j = 0; j < cor3_num; j++ ) {
    fprintf ( fileout, "%f %f %f\n", cor3[0][j], cor3[1][j], cor3[2][j] );
    text_num = text_num + 1;
  }

  for ( iface = 0; iface < face_num; iface++ ) {

    for ( ivert = 0; ivert < face_order[iface]; ivert++ ) {

      jp = face[ivert][iface] + 1;
      if ( ivert == face_order[iface] - 1 ) {
        jp = - jp;
      }
     fprintf ( fileout, "%d ", jp );
    }
    fprintf ( fileout, "\n" );
    text_num = text_num + 1;
  }
/*
  Report.
*/
  printf ( "\n" );
  printf ( "BYU_WRITE - Wrote %d text lines.\n", text_num );

  return SUCCESS;
}
/******************************************************************************/

int char_index_last ( char* string, char c )

/******************************************************************************/

/*
  Purpose:

    CHAR_INDEX_LAST reports the last occurrence of a character in a string.

  Author:
 
    John Burkardt
*/
{
  int i;
  int j;
  int nchar;

  j = -1;

  nchar = strlen ( string );

  for ( i = 0; i < nchar; i++ ) {
    if ( string[i] == c ) {
      j = i;
    }
  }

  return j;

}
/******************************************************************************/

int char_pad ( int *char_index, int *null_index, char *string, 
  int STRING_MAX )

/******************************************************************************/

/*
  Purpose:

    CHAR_PAD "pads" a character in a string with a blank on either side.

  Modified:

    16 October 1998

  Author:

    John Burkardt

  Parameters:

    Input/output, int *CHAR_INDEX, the position of the character to be padded.
    On output, this is increased by 1.

    Input/output, int *NULL_INDEX, the position of the terminating NULL in 
    the string.  On output, this is increased by 2.

    Input/output, char STRING[STRING_MAX], the string to be manipulated.

    Input, int STRING_MAX, the maximum number of characters that can be stored
    in the string.

    Output, int CHAR_PAD, is SUCCESS if the operation worked, and ERROR otherwise.
*/
{
  int i;

  if ( *char_index < 0 || 
       *char_index >= *null_index || 
       *char_index > STRING_MAX-1 ) {
    return ERROR;
  }

  if ( (*null_index) + 2 > STRING_MAX-1 ) {
    return ERROR;
  }

  for ( i = *null_index + 2; i > *char_index + 2; i-- ) {
    string[i] = string[i-2];
  }
  string[*char_index+2] = ' ';
  string[*char_index+1] = string[*char_index];
  string[*char_index] = ' ';

  *char_index = *char_index + 1;
  *null_index = *null_index + 2;

  return SUCCESS;
}
/******************************************************************************/

char char_read ( FILE *filein )

/******************************************************************************/

/*
  Purpose:

    CHAR_READ reads one character from a binary file.

  Modified:

    24 May 1999

  Author:

    John Burkardt
*/
{
  char c;

  c = ( char ) fgetc ( filein );

  return c;
}
/******************************************************************************/

int char_write ( FILE *fileout, char c )

/******************************************************************************/

/*
  Purpose:

    CHAR_WRITE writes one character to a binary file.

  Modified:

    24 May 1999

  Author:

    John Burkardt
*/
{
  fputc ( c, fileout );

  return 1;
}
/******************************************************************************/

int command_line ( char **argv )

/******************************************************************************/

/*

  Purpose:

    COMMAND_LINE carries out a command-line session of file conversion.

  Discussion:

    This routine is invoked when the user command is something like

      ivcon filein_name fileout_name

    or

      ivcon -rn filein_name fileout_name

    where "-rn" signals the "reverse normals" option, or

      ivcon -rf filein_name fileout_name

    where "-rf" signals the "reverse faces" option.

  Modified:

    28 June 1999

  Author:
 
    John Burkardt
*/
{
  int   i;
  int   iarg;
  int   icor3;
  int   ierror;
  int   iface;
  int   ivert;
  int   reverse_faces;
  int   reverse_normals;
/* 
  Initialize local data. 
*/
  iarg = 0;
  ierror = 0;
  reverse_faces = FALSE;
  reverse_normals = FALSE;
/*
  Initialize the graphics data.
*/
  data_init ( );
/*
  Get the -RN option, -RF option, and the input file name. 
*/
  iarg = iarg + 1;
  strcpy ( filein_name, argv[iarg] );

  if ( leqi ( filein_name, "-RN" ) == TRUE ) {
    reverse_normals = TRUE;
    printf ( "\n" );
    printf ( "COMMAND_LINE: Reverse_Normals option requested.\n" );
    iarg = iarg + 1;
    strcpy ( filein_name, argv[iarg] );
  }

  if ( leqi ( filein_name, "-RF" ) == TRUE ) {
    reverse_faces = TRUE;
    printf ( "\n" );
    printf ( "COMMAND_LINE: Reverse_Faces option requested.\n" );
    iarg = iarg + 1;
    strcpy ( filein_name, argv[iarg] );
  }
/*
  Read the input. 
*/
  ierror = data_read ( );

  if ( ierror == ERROR ) {
    printf ( "\n" );
    printf ( "COMMAND_LINE - Fatal error!\n" );
    printf ( "  Failure while reading input data.\n" );
    return ERROR;
  }
/*
  Reverse the normal vectors if requested.
*/
  if ( reverse_normals == TRUE ) {

    for ( icor3 = 0; icor3 < cor3_num; icor3++ ) {
      for ( i = 0; i < 3; i++ ) {
        cor3_normal[i][icor3] = - cor3_normal[i][icor3];
      }
    }

    for ( iface = 0; iface < face_num; iface++ ) {
      for ( i = 0; i < 3; i++ ) {
        face_normal[i][iface] = - face_normal[i][iface];
      }
    }

    for ( iface = 0; iface < face_num; iface++ ) {
      for ( ivert = 0; ivert < face_order[iface]; ivert++ ) {
        for ( i = 0; i < 3; i++ ) {
          vertex_normal[i][ivert][iface] = 
            - vertex_normal[i][ivert][iface];
        }
      }
    }
    printf ( "\n" );
    printf ( "COMMAND_LINE - Note:\n" );
    printf ( "  Reversed node, face, and vertex normals.\n" );
  }
/*
  Reverse the faces if requested.
*/
  if ( reverse_faces == TRUE ) {

    face_reverse_order ( );

    printf ( "\n" );
    printf ( "COMMAND_LINE - Note:\n" );
    printf ( "  Reversed the face definitions.\n" );
  }
/*
  Write the output file. 
*/
  iarg = iarg + 1;
  strcpy ( fileout_name, argv[iarg] );

  ierror = data_write ( );

  if ( ierror == ERROR ) {
    printf ( "\n" );
    printf ( "COMMAND_LINE - Fatal error!\n" );
    printf ( "  Failure while writing output data.\n" );
    return ERROR;
  }
  return SUCCESS;
}
/******************************************************************************/

void cor3_normal_set ( void )

/******************************************************************************/

/*
  Purpose:

    COR3_NORMAL_SET computes node normal vectors.

  Modified:

    18 November 1998

  Author:

    John Burkardt
*/
{
  int   icor3;
  int   iface;
  int   ivert;
  int   j;
  float norm;
  float temp;

  for ( icor3 = 0; icor3 < cor3_num; icor3++ ) {
    for ( j = 0; j < 3; j++ ) {
      cor3_normal[j][icor3] = 0.0;
    }
  }
/*
  Add up the normals at all the faces to which the node belongs.
*/
  for ( iface = 0; iface < face_num; iface++ ) {

    for ( ivert = 0; ivert < face_order[iface]; ivert++ ) {

      icor3 = face[ivert][iface];

      for ( j = 0; j < 3; j++ ) {
        cor3_normal[j][icor3] = cor3_normal[j][icor3]
          + vertex_normal[j][ivert][iface];
      }
    }
  }
/*
  Renormalize.
*/
  for ( icor3 = 0; icor3 < cor3_num; icor3++ ) {

    norm = 0.0;
    for ( j = 0; j < 3; j++ ) {
      temp = cor3_normal[j][icor3];
      norm = norm + temp * temp;
    }

    if ( norm == 0.0 ) {
      norm = 3.0;
      for ( j = 0; j < 3; j++ ) {
        cor3_normal[j][icor3] = 1.0;
      }
    }

    norm = ( float ) sqrt ( norm );

    for ( j = 0; j < 3; j++ ) {
      cor3_normal[j][icor3] = cor3_normal[j][icor3] / norm;
    }
  }

  return;
}
/******************************************************************************/

void cor3_range ( void )

/******************************************************************************/

/*
  Purpose:

    COR3_RANGE computes the coordinate minima and maxima.

  Modified:

    31 August 1998

  Author:

    John Burkardt
*/
{
  int   i;
  float xave;
  float xmax;
  float xmin;
  float yave;
  float ymax;
  float ymin;
  float zave;
  float zmax;
  float zmin;

  xave = cor3[0][0];
  xmax = cor3[0][0];
  xmin = cor3[0][0];

  yave = cor3[1][0];
  ymax = cor3[1][0];
  ymin = cor3[1][0];

  zave = cor3[2][0];
  zmax = cor3[2][0];
  zmin = cor3[2][0];

  for ( i = 1; i < cor3_num; i++ ) {

    xave = xave + cor3[0][i];
    if ( cor3[0][i] < xmin ) {
      xmin = cor3[0][i];
    }
    if ( cor3[0][i] > xmax ) {
      xmax = cor3[0][i];
    }

    yave = yave + cor3[1][i];
    if ( cor3[1][i] < ymin ) {
      ymin = cor3[1][i];
    }
    if ( cor3[1][i] > ymax ) {
      ymax = cor3[1][i];
    }

    zave = zave + cor3[2][i];
    if ( cor3[2][i] < zmin ) {
      zmin = cor3[2][i];
    }
    if ( cor3[2][i] > zmax ) {
      zmax = cor3[2][i];
    }
  }

  xave = xave / cor3_num;
  yave = yave / cor3_num;
  zave = zave / cor3_num;

  printf ( "\n" );
  printf ( "COR3_RANGE - Data range:\n" );
  printf ( "\n" );
  printf ( "   Minimum   Average   Maximum  Range\n" );
  printf ( "\n" );
  printf ( "X  %f %f %f %f\n", xmin, xave, xmax, xmax-xmin );
  printf ( "Y  %f %f %f %f\n", ymin, yave, ymax, ymax-ymin );
  printf ( "Z  %f %f %f %f\n", zmin, zave, zmax, zmax-zmin );

}
/******************************************************************************/

void data_check ( void )

/******************************************************************************/

/*
  Purpose:
   
    DATA_CHECK checks the input data.

  Modified:

    18 May 1999

  Author:
 
    John Burkardt
*/
{
  int iface;
  int nfix;

  if ( color_num > COLOR_MAX ) {
    printf ( "\n" );
    printf ( "DATA_CHECK - Warning!\n" );
    printf ( "  The input data requires %d colors.\n", color_num );
    printf ( "  There was only room for %d\n", COLOR_MAX );
    color_num = COLOR_MAX;
  }
  
  if ( cor3_num > COR3_MAX ) {
    printf ( "\n" );
    printf ( "DATA_CHECK - Warning!\n" );
    printf ( "  The input data requires %d points.\n", cor3_num );
    printf ( "  There was only room for %d\n", COR3_MAX );
    cor3_num = COR3_MAX;
  }

  if ( face_num > FACE_MAX ) {
    printf ( "\n" );
    printf ( "DATA_CHECK - Warning!\n" );
    printf ( "  The input data requires %d faces.\n", face_num );
    printf ( "  There was only room for %d\n", FACE_MAX );
    face_num = FACE_MAX;
  }

  if ( line_num > LINES_MAX ) {
    printf ( "\n" );
    printf ( "DATA_CHECK - Warning!\n" );
    printf ( "  The input data requires %d line items.\n", line_num );
    printf ( "  There was only room for %d.\n", LINES_MAX );
    line_num = LINES_MAX;
  }

  nfix = 0;

  for ( iface = 0; iface < face_num; iface++ ) {

    if ( face_order[iface] > ORDER_MAX ) {
      face_order[iface] = ORDER_MAX;
      nfix = nfix + 1;
    }

  }

  if ( nfix > 0 ) {
    printf ( "\n" );
    printf ( "DATA_CHECK - Warning!\n" );
    printf ( "  Corrected %d faces using more than %d vertices per face.\n",
      nfix, ORDER_MAX );
  }

  for ( i = 0; i < material_num; i++ ) {
    if ( strcmp ( material_name[i], "" ) == 0 ) {
      strcpy ( material_name[i], "Material_0000" );
    }
  }

  for ( i = 0; i < texture_num; i++ ) {
    if ( strcmp ( texture_name[i], "" ) == 0 ) {
      strcpy ( texture_name[i], "Texture_0000" );
    }
  }

  printf ( "\n" );
  printf ( "DATA_CHECK - Data checked.\n" );

  return;
}
/******************************************************************************/

void data_init ( void )

/******************************************************************************/

/*
  Purpose:

    DATA_INIT initializes the internal graphics data.

  Modified:

    04 July 2000

  Author:

    John Burkardt
*/
{
  int i;
  int iface;
  int ivert;
  int j;
  int k;

  strcpy( anim_name, "" );

  for ( i = 0; i < 3; i++ ) {
    background_rgb[i] = 0.0;
  }

  for ( i = 0; i < 3; i++ ) {
    for ( j = 0; j < COR3_MAX; j++ ) {
      cor3[i][j] = 0.0;
    }
  }

  for ( i = 0; i < COR3_MAX; i++ ) {
    cor3_material[i] = 0;
  }

  for ( i = 0; i < 3; i++ ) {
    for ( j = 0; j < COR3_MAX; j++ ) {
      cor3_normal[i][j] = 0.0;
    }
  }

  for ( j = 0; j < COR3_MAX; j++ ) {
    cor3_tex_uv[0][j] = 0.0;
    cor3_tex_uv[1][j] = 0.0;
  }

  for ( iface = 0; iface < FACE_MAX; iface++ ) {
    for ( ivert = 0; ivert < ORDER_MAX; ivert++ ) {
      face[ivert][iface] = 0;
    }
  }

  for ( iface = 0; iface < FACE_MAX; iface++ ) {
    face_flags[iface] = 6;
  }

  for ( iface = 0; iface < FACE_MAX; iface++ ) {
    face_material[iface] = 0;
  }

  for ( iface = 0; iface < FACE_MAX; iface++ ) {
    for ( i = 0; i < 3; i++ ) {
      face_normal[i][iface] = 0;
    }
  }

  for ( iface = 0; iface < FACE_MAX; iface++ ) {
    face_object[iface] = -1;
  }

  for ( iface = 0; iface < FACE_MAX; iface++ ) {
    face_order[iface] = 0;
  }

  for ( iface = 0; iface < FACE_MAX; iface++ ) {
    face_smooth[iface] = 1;
  }

  for ( i = 0; i < LINES_MAX; i++ ) {
    line_dex[i] = -1;
  }

  for ( i = 0; i < LINES_MAX; i++ ) {
    line_material[i] = 0;
  }

  strcpy ( material_binding, "DEFAULT" );

  for ( j = 0; j < MATERIAL_MAX; j++ ) {
    strcpy ( material_name[j], "Material_0000" );
  }

  for ( i = 0; i < 4; i++ ) {
    for ( j = 0; j < MATERIAL_MAX; j++ ) {
      material_rgba[i][j] = 0.0;
    }
  }

  strcpy ( normal_binding, "DEFAULT" );

  for ( j = 0; j < ORDER_MAX*FACE_MAX; j++ ) {
    for ( i = 0; i < 3; i++ ) {
      normal_temp[i][j] = 0;
    }
  }

  color_num = 0;
  cor3_num = 0;
  face_num = 0;
  group_num = 0;
  line_num = 0;
  material_num = 0;
  object_num = 0;
  texture_num = 0;

  strcpy ( object_name, "IVCON" );

  for ( i = 0; i < 3; i++ ) {
    origin[i] = 0.0;
  }

  for ( i = 0; i < 3; i++ ) {
    pivot[i] = 0.0;
  }

  for ( j = 0; j < COLOR_MAX; j++ ) {
    rgbcolor[0][j] = 0.299;
    rgbcolor[1][j] = 0.587;
    rgbcolor[2][j] = 0.114;
  }

  strcpy ( texture_binding, "DEFAULT" );

  for ( j = 0; j < TEXTURE_MAX; j++ ) {
    strcpy ( texture_name[j], "Texture_0000" );
  }

  tmat_init ( transform_matrix );

  for ( iface = 0; iface < FACE_MAX; iface++ ) {
    for ( ivert = 0; ivert < ORDER_MAX; ivert++ ) {
      vertex_material[ivert][iface] = 0;
    }
  }

  for ( iface = 0; iface < FACE_MAX; iface++ ) {
    for ( ivert = 0; ivert < ORDER_MAX; ivert++ ) {
      for ( i = 0; i < 3; i++ ) {
        vertex_normal[i][ivert][iface] = 0.0;
      }
    }
  }

  for ( j = 0; j < 3; j++ ) {
    for ( k = 0; k < FACE_MAX; k++ ) {
      vertex_rgb[0][j][k] = 0.299;
      vertex_rgb[1][j][k] = 0.587;
      vertex_rgb[2][j][k] = 0.114;
    }
  }

  for ( iface = 0; iface < FACE_MAX; iface++ ) {
    for ( ivert = 0; ivert < ORDER_MAX; ivert++ ) {
      for ( i = 0; i < 2; i++ ) {
        vertex_tex_uv[i][ivert][iface] = 0.0;
      }
    }
  }

  if ( debug ) {
    printf ( "\n" );
    printf ( "DATA_INIT: Graphics data initialized.\n" );
  }

  return;
}
/******************************************************************************/

int data_read ( void )

/******************************************************************************/

/*
  Purpose:

    DATA_READ reads a file into internal graphics data.

  Modified:

    26 September 1999

  Author:
 
    John Burkardt
*/
{
  FILE *filein;
  char *filein_type;
  int   icor3;
  int   ierror;
  int   iface;
  int   iline;
  int   ivert;
  int   ntemp;
/* 
  Retrieve the input file type. 
*/
  filein_type = file_ext ( filein_name );

  if ( filein_type == NULL ) {
    printf ( "\n" );
    printf ( "DATA_READ - Fatal error!\n" );
    printf ( "  Could not determine the type of '%s'.\n", filein_name );
    return ERROR;
  }
  else if ( debug ) {
    printf ( "\n" );
    printf ( "DATA_READ: Input file has type %s.\n", filein_type );  
  }
/*
  Initialize some data.
*/
  max_order2 = 0;
  bad_num = 0;
  bytes_num = 0;
  comment_num = 0;
  dup_num = 0;
  text_num = 0;
/* 
  Open the file. 
*/
  if ( leqi ( filein_type, "3DS" ) == TRUE ||
       leqi ( filein_type, "STLB" ) == TRUE ||
       leqi ( filein_type, "TRIB" ) == TRUE ) {
    filein = fopen ( filein_name, "rb" );
  }
  else {
    filein = fopen ( filein_name, "r" );
  }

  if ( filein == NULL ) {
    printf ( "\n" );
    printf ( "DATA_READ - Fatal error!\n" );
    printf ( "  Could not open the input file '%s'!\n", filein_name );
    return ERROR;
  }
/*
  Read the information in the file. 
*/
  if ( leqi ( filein_type, "3DS" ) == TRUE ) {

    ierror = tds_read ( filein );
/*
  Cleanup: distribute the node textures to the vertices.
*/
    if ( ierror == SUCCESS ) {

      for ( iface = 0; iface < face_num; iface++ ) {
        for ( ivert = 0; ivert < face_order[iface]; ivert++ ) {
          icor3 = face[ivert][iface];
          vertex_tex_uv[0][ivert][iface] = cor3_tex_uv[0][icor3];
          vertex_tex_uv[1][ivert][iface] = cor3_tex_uv[1][icor3];
        }
      }

    }

  }
  else if ( leqi ( filein_type, "ASE" ) == TRUE ) {

    ierror = ase_read ( filein );

    if ( ierror == SUCCESS ) {

      node_to_vertex_material ( );

      vertex_to_face_material ( );

    }

  }
  else if ( leqi ( filein_type, "BYU" ) == TRUE ) {

    ierror = byu_read ( filein );

  }
  else if ( leqi ( filein_type, "DXF" ) == TRUE ) {

    ierror = dxf_read ( filein );

  }
  else if ( leqi ( filein_type, "GMOD" ) == TRUE ) {

    ierror = gmod_read ( filein );

  }
  else if ( leqi ( filein_type, "HRC" ) == TRUE ) {

    ierror = hrc_read ( filein );

  }
  else if ( leqi ( filein_type, "IV" ) == TRUE ) {

    ierror = iv_read ( filein );

  }
  else if ( leqi ( filein_type, "OBJ" ) == TRUE ) {

    ierror = obj_read ( filein );

  }
  else if ( leqi ( filein_type, "SMF" ) == TRUE ) {

    ierror = smf_read ( filein );

  }
  else if ( 
    leqi ( filein_type, "STL" ) == TRUE ||
    leqi ( filein_type, "STLA") == TRUE ) {

    ierror = stla_read ( filein );

  }
  else if ( leqi ( filein_type, "STLB") == TRUE ) {

    ierror = stlb_read ( filein );

  }
  else if ( 
    leqi ( filein_type, "TRI" ) == TRUE ||
    leqi ( filein_type, "TRIA") == TRUE ) {

    ierror = tria_read ( filein );

  }
  else if ( leqi ( filein_type, "TRIB") == TRUE ) {

    ierror = trib_read ( filein );

  }
  else if ( leqi ( filein_type, "VLA" ) == TRUE ) {

    ierror = vla_read ( filein );

  }
  else {
    printf ( "\n" );
    printf ( "DATA_READ - Fatal error!\n" );
    printf ( "  Unacceptable input file type.\n" );
    return ERROR;
  }

  fclose ( filein );

  if ( debug ) {
    printf ( "DATA_READ: Finished reading the data file.\n" );
  }
/*
  Catch errors reported by the various reading routines.
*/
  if ( ierror == ERROR ) {
    return ierror;
  }
/*
  Restore the transformation matrix.
*/
  tmat_init ( transform_matrix );
/*
  Report on what we read.
*/
  if ( face_num < FACE_MAX ) {
    ntemp = face_num;
  }
  else {
    ntemp = FACE_MAX;
  }

  max_order2 = ivec_max ( ntemp, face_order );

  data_report ( );
/*
  Warn about any errors that occurred during reading.
*/
  if ( ierror == ERROR ) {
    printf ( "\n" );
    printf ( "DATA_READ - Fatal error!\n" );
    printf ( "  An error occurred while reading the input file.\n" );
    return ERROR;
  }
/*
  Check the data.
  You MUST wait until after this check before doing other computations,
  since COR3_NUM and other variables could be much larger than the legal
  maximums, until corrected by DATA_CHECK.
*/
  data_check ( );
/*
  MATERIALS FIXUPS:

  If there are no materials at all, define one.
*/
  if ( material_num < 1 ) {
    material_num = 1;
    strcpy ( material_name[0], "Material_0000" );
    material_rgba[0][0] = 0.7;
    material_rgba[1][0] = 0.7;
    material_rgba[2][0] = 0.7;
    material_rgba[3][0] = 1.0;
  }
/*
  If a node has not been assigned a material, set it to material 0.
*/
  for ( icor3 = 0; icor3 < cor3_num; icor3++ ) {
    if ( cor3_material[icor3] < 0 || cor3_material[icor3] > material_num - 1 ) {
      cor3_material[icor3] = 0;
    }
  }
/*
  If a vertex has not been assigned a material, set it to material 0.
*/
  for ( iface = 0; iface < face_num; iface++ ) {
    for ( ivert = 0; ivert < face_order[iface]; ivert++ ) {
      if ( vertex_material[ivert][iface] < 0 || vertex_material[ivert][iface] > material_num - 1 ) {
        vertex_material[ivert][iface] = 0;
      }
    }
  }
/*
  If a face has not been assigned a material, set it to material 0.
*/
  for ( iface = 0; iface < face_num; iface++ ) {
    if ( face_material[iface] < 0 || face_material[iface] > material_num - 1 ) {
      face_material[iface] = 0;
    }
  }
/*
  If a line item has not been assigned a material, set it to material 0.
*/
  for ( iline = 0; iline < line_num; iline++ ) {
    if ( line_dex[iline] == -1 ) {
      line_material[iline] = -1;
    }
    else if ( line_material[iline] < 0 || line_material[iline] > material_num - 1 ) {
      line_material[iline] = 0;
    }
  }
/*
  Delete edges of zero length.
*/
  edge_null_delete ( );
/*
  Compute the area of each face.
*/
  face_area_set ( );
/*
  Delete faces with zero area.
*/
  face_null_delete ( );
/*
  Recompute zero face-vertex normals from vertex positions.
*/
  vertex_normal_set ( );
/*
  Compute the node normals from the vertex normals.
*/
  cor3_normal_set ( );
/*
  Recompute zero face normals by averaging face-vertex normals.
*/
  face_normal_ave ( );
/*
  Report on the nodal coordinate range.
*/
  cor3_range ( );

  return SUCCESS;
}
/**********************************************************************/

void data_report ( void )

/**********************************************************************/

/*
  Purpose:

    DATA_REPORT gives a summary of the contents of the data file.

  Modified:

    24 May 1999

  Author:

    John Burkardt
*/
{
  printf ( "\n" );
  printf ( "DATA_REPORT - The input file contains:\n" );
  printf ( "\n" );
  printf ( "  Bad data items             %d\n", bad_num );
  printf ( "  Text lines                 %d\n", text_num );
  printf ( "  Text bytes (binary data)   %d\n", bytes_num );
  printf ( "  Colors                     %d\n", color_num );
  printf ( "  Comments                   %d\n", comment_num );
  printf ( "  Duplicate points           %d\n", dup_num );
  printf ( "  Faces                      %d\n", face_num );
  printf ( "  Groups                     %d\n", group_num );
  printf ( "  Vertices per face, maximum %d\n", max_order2 );
  printf ( "  Line items                 %d\n", line_num );
  printf ( "  Points                     %d\n", cor3_num );
  printf ( "  Objects                    %d\n", object_num );

  return;
}
/******************************************************************************/

int data_write ( void )

/******************************************************************************/

/*
  Purpose:

    DATA_WRITE writes the internal graphics data to a file.

  Modified:

    22 May 1999

  Author:
 
    John Burkardt
*/
{
  FILE *fileout;
  char *fileout_type;
  int   line_num_save;
  int   result;

  result = SUCCESS;
/* 
  Retrieve the output file type. 
*/
  fileout_type = file_ext ( fileout_name );

  if ( fileout_type == NULL ) {
    printf ( "\n" );
    printf ( "DATA_WRITE - Fatal error!\n" );
    printf ( "  Could not determine the output file type.\n" );
    return ERROR;
  }
/* 
  Open the output file. 
*/
  if ( leqi ( fileout_type, "3DS" ) == TRUE ||
       leqi ( fileout_type, "STLB" ) == TRUE ||
       leqi ( fileout_type, "TRIB" ) ) {
    fileout = fopen ( fileout_name, "wb" );
  }
  else {
    fileout = fopen ( fileout_name, "w" );
  }

  if ( fileout == NULL ) {
    printf ( "\n" );
    printf ( "DATA_WRITE - Fatal error!\n" );
    printf ( "  Could not open the output file!\n" );
    return ERROR;
  }
/* 
  Write the output file. 
*/
  if ( leqi ( fileout_type, "3DS" ) == TRUE ) {

    tds_pre_process();
    result = tds_write ( fileout );

  }
  else if ( leqi ( fileout_type, "ASE" ) == TRUE ) {

    result = ase_write ( fileout );

  }
  else if ( leqi ( fileout_type, "BYU" ) == TRUE ) {

    result = byu_write ( fileout );

  }
  else if ( leqi ( fileout_type, "DXF" ) == TRUE ) {

    result = dxf_write ( fileout );

  }
  else if ( leqi ( fileout_type, "GMOD" ) == TRUE ) {

    result = gmod_write ( fileout );

  }
  else if ( leqi ( fileout_type, "HRC" ) == TRUE ) {

    result = hrc_write ( fileout );

  }
  else if ( leqi ( fileout_type, "IV" ) == TRUE ) {

    result = iv_write ( fileout );

  }
  else if ( leqi ( fileout_type, "OBJ" ) == TRUE ) {

    result = obj_write ( fileout );

  }
  else if ( leqi ( fileout_type, "POV" ) == TRUE ) {

    result = pov_write ( fileout );

  }
  else if ( leqi ( fileout_type, "SMF" ) == TRUE ) {

    result = smf_write ( fileout );

  }
  else if ( 
    leqi ( fileout_type, "STL" ) == TRUE ||
    leqi ( fileout_type, "STLA" ) == TRUE ) {

    result = stla_write ( fileout );

  }
  else if ( leqi ( fileout_type, "STLB" ) == TRUE ) {

    result = stlb_write ( fileout );

  }
  else if ( leqi ( fileout_type, "TEC" ) == TRUE ) {

    result = tec_write ( fileout );

  }
  else if ( 
    leqi ( fileout_type, "TRI" ) == TRUE ||
    leqi ( fileout_type, "TRIA" ) == TRUE ) {

    result = tria_write ( fileout );

  }
  else if ( leqi ( fileout_type, "TRIB" ) == TRUE ) {

    result = trib_write ( fileout );

  }
  else if ( leqi ( fileout_type, "TXT" ) == TRUE ) {

    result = txt_write ( fileout );

  }
  else if ( leqi ( fileout_type, "UCD" ) == TRUE ) {

    result = ucd_write ( fileout );

  }
  else if ( leqi ( fileout_type, "VLA" ) == TRUE ) {

    line_num_save = line_num;

    if ( face_num > 0 ) {

      printf ( "\n" );
      printf ( "DATA_WRITE - Note:\n" );
      printf ( "  Face information will temporarily be converted to\n" );
      printf ( "  line information for output to a VLA file.\n" );

      face_to_line ( );

      if ( line_num > LINES_MAX ) {
        printf ( "\n" );
        printf ( "DATA_WRITE - Warning:\n" );
        printf ( "  Some face information was lost.\n" );
        printf ( "  The maximum number of lines is %d.\n", LINES_MAX );
        printf ( "  The number of lines needed is %d.\n", line_num );
        line_num = LINES_MAX;
      }

    }

    result = vla_write ( fileout );

    line_num = line_num_save;

  }
  else if ( leqi ( fileout_type, "WRL" ) == TRUE ) {

    result = wrl_write ( fileout );

  }
  else if ( leqi ( fileout_type, "XGL" ) == TRUE ) {

    result = xgl_write ( fileout );

  }
  else {

    result = ERROR;
    printf ( "\n" );
    printf ( "DATA_WRITE - Fatal error!\n" );
    printf ( "  Unacceptable output file type \"%s\".\n", fileout_type );

  }
/*  
  Close the output file. 
*/
  fclose ( fileout );

  if ( result == ERROR ) {
    return ERROR;
  }
  else {
    return SUCCESS;
  }
}
/******************************************************************************/

int dxf_read ( FILE *filein )

/******************************************************************************/

/*
  Purpose:
   
    DXF_READ reads an AutoCAD DXF file.

  Examples:

      0
    SECTION
      2
    HEADER
    999
    diamond.dxf created by IVREAD.
    999
    Original data in diamond.obj.
      0
    ENDSEC
      0
    SECTION
      2
    TABLES
      0
    ENDSEC
      0
    SECTION
      2
    BLOCKS
      0
    ENDSEC
      0
    SECTION
      2
    ENTITIES
      0
    LINE
      8
    0
     10
      0.00  (X coordinate of beginning of line.)
     20
      0.00  (Y coordinate of beginning of line.)
     30
      0.00  (Z coordinate of beginning of line.)
     11
      1.32  (X coordinate of end of line.)
     21
      1.73  (Y coordinate of end of line.)
     31
      2.25  (Z coordinate of end of line.)
      0
    3DFACE
      8
     Cube
    10
    -0.50  (X coordinate of vertex 1)
    20
     0.50  (Y coordinate of vertex 1)   
    30
      1.0  (Z coordinate of vertex 1)  
    11
     0.50  (X coordinate of vertex 2)  
    21
     0.50  (Y coordinate of vertex 2)
    31
      1.0  (Z coordinate of vertex 2)
    12
     0.50  (X coordinate of vertex 3) 
    22
     0.50  (Y coordinate of vertex 3)
    32
     0.00  (Z coordinate of vertex 3)
      0
    ENDSEC
      0
    EOF

  Modified:

    23 May 1999

  Author:
 
    John Burkardt
*/
{
  int   code;
  int   count;
  float cvec[3];
  int   icor3;
  char  input1[LINE_MAX_LEN];
  char  input2[LINE_MAX_LEN];
  int   ivert;
  float rval;
  int   width;
  int   linemode;
  int   cpos;

  linemode = 0;
  ivert = 0;
/* 
  Read the next two lines of the file into INPUT1 and INPUT2. 
*/

  for ( ;; ) {

/* 
  INPUT1 should contain a single integer, which tells what INPUT2
  will contain.
*/
    if ( fgets ( input1, LINE_MAX_LEN, filein ) == NULL ) {
      break;
    }

    text_num = text_num + 1;

    count = sscanf ( input1, "%d%n", &code, &width );
    if ( count <= 0 ) {
      break;
    }
/*
  Read the second line, and interpret it according to the code.
*/
    if ( fgets ( input2, LINE_MAX_LEN, filein ) == NULL ) {
      break;
    }

    text_num = text_num + 1;

    if ( code == 0 ) {
    
      if ( ivert > 0 ) {
        /* finish off the face */
        face_order[face_num] = ivert;
        face_num = face_num + 1;
        ivert = 0;
      }
      
      if ( strncmp( input2, "LINE", 4 ) == 0 ) {
        linemode = 1;
      }
      else if ( strncmp( input2, "3DFACE", 6 ) == 0 ) {
        linemode = 0;
        ivert = 0;
      }
    }
    else {
      
      for (cpos = 0; input1[cpos] == ' '; cpos++) 
      {};
      
      if ( input1[cpos] == '1' || input1[cpos] == '2' || input1[cpos] == '3' ) {

        count = sscanf ( input2, "%e%n", &rval, &width );

        switch ( input1[cpos] )
        {
          case '1':
            if ( line_num > 0 ) {
              if ( linemode ) {
                line_dex[line_num] = - 1;
                line_material[line_num] = - 1;
                line_num = line_num + 1;
              }
            }
            cvec[0] = rval;
            break;

          case '2':
            cvec[1] = rval;
            break;

          case '3':
            cvec[2] = rval;

            if ( cor3_num < 1000 ) {
              icor3 = rcol_find ( cor3, 3, cor3_num, cvec );
            } 
            else {
              icor3 = -1;
            }

            if ( icor3 == -1 ) {
              icor3 = cor3_num;
              if ( cor3_num < COR3_MAX ) {
                cor3[0][cor3_num] = cvec[0];
                cor3[1][cor3_num] = cvec[1];
                cor3[2][cor3_num] = cvec[2];
              }
              cor3_num = cor3_num + 1;
            }
            else {
              dup_num = dup_num + 1;
            }

            if ( linemode ) {
              line_dex[line_num] = icor3;
              line_material[line_num] = 0;
              line_num = line_num + 1;
            }
            else {
              face[ivert][face_num] = icor3;
              ivert = ivert + 1;
            }
            break;
        
          default:
            break;
        }
      }
    }
  }

  if ( line_num > 0 ) {
    if ( linemode ) {
      line_dex[line_num] = - 1;
      line_material[line_num] = - 1;
      line_num = line_num + 1;
    }
  }
  return SUCCESS;
}
/******************************************************************************/

int dxf_write ( FILE *fileout )

/******************************************************************************/

/*
  Purpose:
   
    DXF_WRITE writes graphics information to an AutoCAD DXF file.

  Examples:

      0
    SECTION
      2
    HEADER
    999
    diamond.dxf created by IVREAD.
    999
    Original data in diamond.obj.
      0
    ENDSEC
      0
    SECTION
      2
    TABLES
      0
    ENDSEC
      0
    SECTION
      2
    BLOCKS
      0
    ENDSEC
      0
    SECTION
      2
    ENTITIES
      0
    LINE
      8
    0
     10
      0.00  (X coordinate of beginning of line.)
     20
      0.00  (Y coordinate of beginning of line.)
     30
      0.00  (Z coordinate of beginning of line.)
     11
      1.32  (X coordinate of end of line.)
     21
      1.73  (Y coordinate of end of line.)
     31
      2.25  (Z coordinate of end of line.)
      0
    3DFACE
      8
     Cube
    10
    -0.50  (X coordinate of vertex 1)
    20
     0.50  (Y coordinate of vertex 1)   
    30
      1.0  (Z coordinate of vertex 1)  
    11
     0.50  (X coordinate of vertex 2)  
    21
     0.50  (Y coordinate of vertex 2)
    31
      1.0  (Z coordinate of vertex 2)
    12
     0.50  (X coordinate of vertex 3) 
    22
     0.50  (Y coordinate of vertex 3)
    32
     0.00  (Z coordinate of vertex 3)
      0
    ENDSEC
      0
    EOF

  Modified:

    16 May 1999

  Author:
 
    John Burkardt
*/
{
  int   icor3;
  int   iline;
  int   iface;
  int   ivert;
  int   jcor3;
  int   newline;
  int   text_num;

/* 
  Initialize. 
*/
  text_num = 0;

  fprintf ( fileout, "  0\n" );
  fprintf ( fileout, "SECTION\n" );
  fprintf ( fileout, "  2\n" );
  fprintf ( fileout, "HEADER\n" );
  fprintf ( fileout, "999\n" );
  fprintf ( fileout, "%s created by IVCON.\n", fileout_name );
  fprintf ( fileout, "999\n" );
  fprintf ( fileout, "Original data in %s.\n", filein_name );
  fprintf ( fileout, "  0\n" );
  fprintf ( fileout, "ENDSEC\n" );
  text_num = text_num + 10;

  fprintf ( fileout, "  0\n" );
  fprintf ( fileout, "SECTION\n" );
  fprintf ( fileout, "  2\n" );
  fprintf ( fileout, "TABLES\n" );
  fprintf ( fileout, "  0\n" );
  fprintf ( fileout, "ENDSEC\n" );
  text_num = text_num + 6;

  fprintf ( fileout, "  0\n" );
  fprintf ( fileout, "SECTION\n" );
  fprintf ( fileout, "  2\n" );
  fprintf ( fileout, "BLOCKS\n" );
  fprintf ( fileout, "  0\n" );
  fprintf ( fileout, "ENDSEC\n" );
  text_num = text_num + 6;

  fprintf ( fileout, "  0\n" );
  fprintf ( fileout, "SECTION\n" );
  fprintf ( fileout, "  2\n" );
  fprintf ( fileout, "ENTITIES\n" );
  text_num = text_num + 4;
/*
  Handle lines.
*/
  jcor3 = 0;
  newline = TRUE;

  for ( iline = 0; iline < line_num; iline++ ) {
    
    icor3 = line_dex[iline];

    if ( icor3 == -1 ) {

      newline = TRUE;
    }
    else {

      if ( newline == FALSE ) {

        fprintf ( fileout, "  0\n" );
        fprintf ( fileout, "LINE\n" );
        fprintf ( fileout, "  8\n" );
        fprintf ( fileout, "  0\n" );
        fprintf ( fileout, " 10\n" );
        fprintf ( fileout, "%f\n", cor3[0][jcor3] );
        fprintf ( fileout, " 20\n" );
        fprintf ( fileout, "%f\n", cor3[1][jcor3] );
        fprintf ( fileout, " 30\n" );
        fprintf ( fileout, "%f\n", cor3[2][jcor3] );
        fprintf ( fileout, " 11\n" );
        fprintf ( fileout, "%f\n", cor3[0][icor3] );
        fprintf ( fileout, " 21\n" );
        fprintf ( fileout, "%f\n", cor3[1][icor3] );
        fprintf ( fileout, " 31\n" );
        fprintf ( fileout, "%f\n", cor3[2][icor3] );

        text_num = text_num + 16;

      }

      jcor3 = icor3;
      newline = FALSE;

    }
  }
/*
  Handle faces.
  (If FACE_ORDER is greater than 10, you're sure to have problems here)
*/
  for ( iface = 0; iface < face_num; iface++ ) {
    
    fprintf ( fileout, "  0\n" );
    fprintf ( fileout, "3DFACE\n" );
    fprintf ( fileout, "  8\n" );
    fprintf ( fileout, "  Cube\n" );
    text_num = text_num + 4;
    
    for ( ivert = 0; ivert < face_order[iface]; ivert++ ) {

      icor3 = face[ivert][iface];
      
      fprintf ( fileout, "1%d\n", ivert );
      fprintf ( fileout, "%f\n", cor3[0][icor3] );
      fprintf ( fileout, "2%d\n", ivert );
      fprintf ( fileout, "%f\n", cor3[1][icor3] );
      fprintf ( fileout, "3%d\n", ivert );
      fprintf ( fileout, "%f\n", cor3[2][icor3] );

      text_num = text_num + 6;
    }
  }

  fprintf ( fileout, "  0\n" );
  fprintf ( fileout, "ENDSEC\n" );
  fprintf ( fileout, "  0\n" );
  fprintf ( fileout, "EOF\n" );
  text_num = text_num + 4;
/*
  Report.
*/
  printf ( "\n" );
  printf ( "DXF_WRITE - Wrote %d text lines.\n", text_num );

  return SUCCESS;
}
/**********************************************************************/

void edge_null_delete ( void )

/**********************************************************************/

/*
  Purpose:

    EDGE_NULL_DELETE deletes face edges with zero length.

  Modified:

    16 July 1999

  Author:

    John Burkardt
*/
{
  float distsq;
  int face2[ORDER_MAX];
  int face_order2;
  int iface;
  int inode;
  int ivert;
  int j;
  int jnode;
  int jvert;
  int edge_num;
  int edge_num_del;
  float vertex_normal2[3][ORDER_MAX];
  float x;
  float y;
  float z;

  edge_num = 0;
  edge_num_del = 0;
/*
  Consider each face.
*/
  for ( iface = 0; iface < face_num; iface++ ) {
/*
  Consider each pair of consecutive vertices.
*/
    face_order2 = 0;

    for ( ivert = 0; ivert < face_order[iface]; ivert++ ) {

      edge_num = edge_num + 1;

      jvert = ivert + 1;
      if ( jvert >= face_order[iface] ) {
        jvert = 0;
      }

      inode = face[ivert][iface];
      jnode = face[jvert][iface];


      x = cor3[0][inode] - cor3[0][jnode];
      y = cor3[1][inode] - cor3[1][jnode];
      z = cor3[2][inode] - cor3[2][jnode];

      distsq = x * x + y * y + z * z;

      if ( distsq != 0.0 ) {
        face2[face_order2] = face[ivert][iface];
        vertex_normal2[0][face_order2] = vertex_normal[0][ivert][iface];
        vertex_normal2[1][face_order2] = vertex_normal[1][ivert][iface];
        vertex_normal2[2][face_order2] = vertex_normal[2][ivert][iface];
        face_order2 = face_order2 + 1;
      }
      else {
        edge_num_del = edge_num_del + 1;
      }

    }

    face_order[iface] = face_order2;
    for ( ivert = 0; ivert < face_order[iface]; ivert++ ) {
      face[ivert][iface] = face2[ivert];
      for ( j = 0; j < 3; j++ ) {
        vertex_normal[j][ivert][iface] = vertex_normal2[j][ivert];
      }
    }

  }

  printf ( "\n" );
  printf ( "EDGE_NULL_DELETE:\n" );
  printf ( "  There are a total of %d edges.\n", edge_num );
  printf ( "  Of these, %d were of zero length, and deleted.\n", edge_num_del );

  return;
}
/**********************************************************************/

void face_area_set ( void )

/**********************************************************************/

/*
  Purpose:

    FACE_AREA_SET computes the area of the faces.

  Formula:

    The area is the sum of the areas of the triangles formed by
    node N with consecutive pairs of nodes.

  Reference:

    Adrian Bowyer and John Woodwark,
    A Programmer's Geometry,
    Butterworths, 1983.

  Modified:

    17 July 1999

  Author:

    John Burkardt
*/
{
  float alpha;
  float area_max;
  float area_min;
  float area_tri;
  float base;
  float dot;
  float height;
  int i;
  int i1;
  int i2;
  int i3;
  int iface;
  int face_num_del;
  float tol;
  float x;
  float x1;
  float x2;
  float x3;
  float y;
  float y1;
  float y2;
  float y3;
  float z;
  float z1;
  float z2;
  float z3;

  for ( iface = 0; iface < face_num; iface++ ) {

    face_area[iface] = 0.0;

    for ( i = 0; i < face_order[iface]-2; i++ ) {

      i1 = face[i][iface];
      i2 = face[i+1][iface];
      i3 = face[i+2][iface];

      x1 = cor3[0][i1];
      y1 = cor3[1][i1];
      z1 = cor3[2][i1];

      x2 = cor3[0][i2];
      y2 = cor3[1][i2];
      z2 = cor3[2][i2];

      x3 = cor3[0][i3];
      y3 = cor3[1][i3];
      z3 = cor3[2][i3];
/*
  Find the projection of (P3-P1) onto (P2-P1).
*/
      dot =
        ( x2 - x1 ) * ( x3 - x1 ) +
        ( y2 - y1 ) * ( y3 - y1 ) +
        ( z2 - z1 ) * ( z3 - z1 );

      base = sqrt (
          ( x2 - x1 ) * ( x2 - x1 )
        + ( y2 - y1 ) * ( y2 - y1 )
        + ( z2 - z1 ) * ( z2 - z1 ) );
/*
  The height of the triangle is the length of (P3-P1) after its
  projection onto (P2-P1) has been subtracted.
*/
      if ( base == 0.0 ) {
        height = 0.0;
      }
      else {

        alpha = dot / ( base * base );

        x = x3 - x1 - alpha * ( x2 - x1 );
        y = y3 - y1 - alpha * ( y2 - y1 );
        z = z3 - z1 - alpha * ( z2 - z1 );

        height = sqrt ( x * x + y * y + z * z );

      }

      area_tri = 0.5 * base * height;

      face_area[iface] = face_area[iface] + area_tri;

    }

  }

  area_min = face_area[0];
  area_max = face_area[0];

  for ( iface = 1; iface < face_num; iface++ ) {
    if ( area_min > face_area[iface] ) {
      area_min = face_area[iface];
    }
    if ( area_max < face_area[iface] ) {
      area_max = face_area[iface];
    }
  }

  printf ( "\n" );
  printf ( "FACE_AREA_SET:\n" );
  printf ( "  Minimum face area is %f\n", area_min );
  printf ( "  Maximum face area is %f\n", area_max );

  tol = area_max / 10000.0;

  if ( area_min < tol ) {

    face_num_del = 0;

    for ( iface = 0; iface < face_num; iface++ ) {
      if ( face_area[iface] < tol ) {
        face_order[iface] = 0;
        face_num_del = face_num_del + 1;
      }
    }

    printf ( "  Marked %d tiny faces for deletion.\n", face_num_del );

  }

  return;
}
/******************************************************************************/

void face_normal_ave ( void )

/******************************************************************************/

/*
  Purpose:

    FACE_NORMAL_AVE sets face normals as average of face vertex normals.

  Modified:

    09 October 1998

  Author:

    John Burkardt
*/
{
  int   i;
  int   iface;
  int   ivert;
  int   nfix;
  float norm;
  float x;
  float y;
  float z;

  if ( face_num <= 0 ) {
    return;
  }
  
  nfix = 0;

  for ( iface = 0; iface < face_num; iface++ ) {

/*
  Check the norm of the current normal vector.
*/
    x = face_normal[0][iface];
    y = face_normal[1][iface];
    z = face_normal[2][iface];
    norm = ( float ) sqrt ( x * x + y * y + z * z );

    if ( norm == 0.0 ) {

      nfix = nfix + 1;

      for ( i = 0; i < 3; i++ ) {
        face_normal[i][iface] = 0.0;
      }

      for ( ivert = 0; ivert < face_order[iface]; ivert++ ) {
        for ( i = 0; i < 3; i++ ) {
          face_normal[i][iface] = face_normal[i][iface] +
            vertex_normal[i][ivert][iface];
        }
      }

      x = face_normal[0][iface];
      y = face_normal[1][iface];
      z = face_normal[2][iface];
      norm = ( float ) sqrt ( x * x + y * y + z * z );

      if ( norm == 0.0 ) {
        for ( i = 0; i < 3; i++ ) {
          face_normal[i][iface] = ( float ) ( 1.0 / sqrt ( 3.0 ) );
        }
      }
      else {
        for ( i = 0; i < 3; i++ ) {
          face_normal[i][iface] = face_normal[i][iface] / norm;
        }
      }
    }
  }

  if ( nfix > 0 ) {
    printf ( "\n" );
    printf ( "FACE_NORMAL_AVE: Recomputed %d face normals\n", nfix );
    printf ( "  by averaging face vertex normals.\n" );
  }
  return;
}
/**********************************************************************/

void face_null_delete ( void )

/**********************************************************************/

/*
  Purpose:

    FACE_NULL_DELETE deletes faces of order less than 3.

  Comments:

    Thanks to Susan M. Fisher, University of North Carolina,
    Department of Computer Science, for pointing out a coding error
    in FACE_NULL_DELETE that was overwriting all the data!

  Modified:

    30 November 1999

  Author:

    John Burkardt
*/
{
  int iface;
  int ivert;
  int j;
  int face_num2;
/*
  FACE_NUM2 is the number of faces we'll keep.
*/
  face_num2 = 0;
/*
  Check every face.
*/
  for ( iface = 0; iface < face_num; iface++ ) {
/*
  Keep it only if it has order 3 or more.
*/
    if ( face_order[iface] >= 3 ) {
/*
  We don't have to slide data down in the array until
  NUMFACE2 and IFACE get out of synch, that is, after
  we've discarded at least one face.
*/
      if ( face_num2 != iface ) {

        face_area[face_num2] = face_area[iface];
        face_material[face_num2] = face_material[iface];
        face_order[face_num2] = face_order[iface];
        for ( ivert = 0; ivert < ORDER_MAX; ivert++ ) {
          face[ivert][face_num2] = face[ivert][iface];
          vertex_material[ivert][face_num2] = vertex_material[ivert][iface];
          for ( j = 0; j < 3; j++ ) {
            vertex_normal[j][ivert][face_num2] = vertex_normal[j][ivert][iface];
          }
        }

      }
/*
  Update the count only after we've used the un-incremented value
  as a pointer.
*/
      face_num2 = face_num2 + 1;

    }

  }

  printf ( "\n" );
  printf ( "FACE_NULL_DELETE\n" );
  printf ( "  There are a total of %d faces.\n", face_num );
  printf ( "  Of these, %d passed the order test.\n", face_num2 );

  face_num = face_num2;

  return;
}
/******************************************************************************/

int face_print ( int iface )

/******************************************************************************/

/*
  Purpose:

    FACE_PRINT prints out information about a face.

  Modified:

    31 August 1998

  Author:

    John Burkardt
*/
{
  int ivert;
  int j;
  int k;

  if ( iface < 0 || iface > face_num-1 ) {
    printf ( "\n" );
    printf ( "FACE_PRINT - Fatal error!\n" );
    printf ( "  Face indices must be between 1 and %d\n", face_num );
    printf ( "  But your requested value was %d\n", iface );
    return ERROR;
  }

  printf ( "\n" );
  printf ( "FACE_PRINT\n" );
  printf ( "  Information about face %d\n", iface );
  printf ( "\n" );
  printf ( "  Number of vertices is %d\n", face_order[iface] );
  printf ( "\n" );
  printf ( "  Vertex list:\n" );
  printf ( "    Vertex #, Node #, Material #, X, Y, Z:\n" );
  printf ( "\n" );
  for ( ivert = 0; ivert < face_order[iface]; ivert++ ) {
    j = face[ivert][iface];
    k = vertex_material[ivert][iface];
    printf ( " %d %d %d %f %f %f\n", ivert, j, k, cor3[0][j], cor3[1][j], 
     cor3[2][j] );
  }

  printf ( "\n" );
  printf ( "  Face normal vector:\n" );
  printf ( "\n" );
  printf ( " %f %f %f\n", face_normal[0][iface], face_normal[1][iface],
    face_normal[2][iface] );

  printf ( "\n" );
  printf ( "  Vertex face normals:\n" );
  printf ( "\n" );
  for ( ivert = 0; ivert < face_order[iface]; ivert++ ) {
    printf ( " %d %f %f %f\n", ivert, vertex_normal[0][ivert][iface],
      vertex_normal[1][ivert][iface], vertex_normal[2][ivert][iface] );
  }

  return SUCCESS;

}
/**********************************************************************/

void face_reverse_order ( void )

/**********************************************************************/

/*
  Purpose:

    FACE_REVERSE_ORDER reverses the order of the nodes in each face.

  Discussion:

    Reversing the order of the nodes requires that the normal vectors
    be reversed as well, so this routine will automatically reverse
    the normals associated with nodes, vertices and faces.

  Modified:

    28 June 1999

  Author:

    John Burkardt
*/
{
  int i;
  int iface;
  int itemp;
  int ivert;
  int j;
  int m;
  float temp;

  for ( iface = 0; iface < face_num; iface++ ) {

    m = face_order[iface];

    for ( ivert = 0; ivert < ( m / 2 ); ivert++ ) {

      itemp = face[ivert][iface];
      face[ivert][iface] = face[m-1-ivert][iface];
      face[m-1-ivert][iface] = itemp;

      itemp = vertex_material[ivert][iface];
      vertex_material[ivert][iface] = vertex_material[m-1-ivert][iface];
      vertex_material[m-1-ivert][iface] = itemp;

      for ( j = 0; j < 3; j++ ) {
        temp = vertex_normal[j][ivert][iface];
        vertex_normal[j][ivert][iface] = vertex_normal[j][m-1-ivert][iface];
        vertex_normal[j][m-1-ivert][iface] = temp;
      }

      for ( j = 0; j < 2; j++ ) {
        temp = vertex_tex_uv[j][ivert][iface];
        vertex_tex_uv[j][ivert][iface] = vertex_tex_uv[j][m-1-ivert][iface];
        vertex_tex_uv[j][m-1-ivert][iface] = temp;
      }

    }

  }

  for ( i = 0; i < cor3_num; i++ ) {
    for ( j = 0; j < 3; j++ ) {
      cor3_normal[j][i] = - cor3_normal[j][i];
    }
  }

  for ( i = 0; i < face_num; i++ ) {
    for ( j = 0; j < 3; j++ ) {
      face_normal[j][i] = - face_normal[j][i];
    }
  }

  printf ( "\n" );
  printf ( "FACE_REVERSE_ORDER\n" );
  printf ( "  Each list of nodes defining a face\n" );
  printf ( "  has been reversed; related information,\n" );
  printf ( "  including normal vectors, was also updated.\n" );

  return;
}

/******************************************************************************/

int face_subset ( void )

/******************************************************************************/

/*
  Purpose:

    FACE_SUBSET selects a subset of the current faces as the new object.

  Warning:

    The original graphic object is overwritten by the new one.

  Modified:

    12 October 1998

  Author:

    John Burkardt

*/
{
  int i;
  int iface;
  int iface1;
  int iface2;
  int inc;
  int ivert;
  int j;
  int k;
  int cor3_num2;

  line_num = 0;
/*
  Get the first and last faces to save, IFACE1 and IFACE2.
*/
  printf ( "\n" );
  printf ( "Enter lowest face number to save between 0 and %d:\n", face_num-1 );
  scanf ( "%d", &iface1 );
  if ( iface1 < 0 || iface1 > face_num - 1 ) {
    printf ( "Illegal choice!\n" );
    return ERROR;
  }

  printf ( "\n" );
  printf ( "Enter highest face number to save between %d and %d:\n", 
    iface1, face_num-1 );
  scanf ( "%d", &iface2 );
  if ( iface2 < iface1 || iface2 > face_num - 1 ) {
    printf ( "Illegal choice!\n" );
    return ERROR;
  }

  inc = iface1;
/*
  "Slide" the data for the saved faces down the face arrays.
*/
  for ( iface = 0; iface < iface2 + 1 - iface1; iface++ ) {
    face_order[iface] = face_order[iface+inc];
    for ( ivert = 0; ivert < ORDER_MAX; ivert++ ) {
      face[ivert][iface] = face[ivert][iface+inc];
      vertex_material[ivert][iface] = vertex_material[ivert][iface+inc];
      for ( i = 0; i < 3; i++ ) {
        vertex_normal[i][ivert][iface] =
          vertex_normal[i][ivert][iface+inc];
        vertex_rgb[i][ivert][iface] = vertex_rgb[i][ivert][iface+inc];
      }
    }
    for ( i = 0; i < 3; i++ ) {
      face_normal[i][iface] = face_normal[i][iface+inc];
    }
  }
/*
  Now reset the number of faces.
*/
  face_num = iface2 + 1 - iface1;
/*
  Now, for each point I, set LIST(I) = J if point I is the J-th
  point we are going to save, and 0 otherwise.  Then J will be
  the new label of point I.
*/
  for ( i = 0; i < cor3_num; i++ ) {
    list[i] = -1;
  }

  cor3_num2 = 0;

  for ( iface = 0; iface < face_num; iface++ ){
    for ( ivert = 0; ivert < face_order[iface]; ivert++ ){
      j = face[ivert][iface];
      if ( list[j] == -1 ) {
        cor3_num2 = cor3_num2 + 1;
        list[j] = cor3_num2;
      }
    }
  }
/*
  Now make the nonzero list entries rise in order, so that
  we can compress the COR3 data in a minute.
*/
  cor3_num2 = 0;

  for ( i = 0; i < cor3_num; i++ ) {
    if ( list[i] != -1 ) {
      list[i] = cor3_num2;
      cor3_num2 = cor3_num2 + 1;
    }
  }
/*
  Relabel the FACE array with the new node indices.
*/
  for ( iface = 0; iface < face_num; iface++ ){
    for ( ivert = 0; ivert < face_order[iface]; ivert++ ){
      j = face[ivert][iface];
      face[ivert][iface] = list[j];
    }
  }
/*
  Rebuild the COR3 array by sliding data down.
*/
  for ( i = 0; i < cor3_num; i++ ){
    k = list[i];
    if ( k != -1 ) {
      for ( j = 0; j < 3; j++ ) {
        cor3[j][k] = cor3[j][i];
      }
    }
  }

  cor3_num = cor3_num2;

  return SUCCESS;
}
/**********************************************************************/

void face_to_line ( void )

/**********************************************************************/

/*
  Purpose:

    FACE_TO_LINE converts face information to line information.

  Discussion:

    In some cases, the graphic information represented by polygonal faces
    must be converted to a representation based solely on line segments.
    This is particularly true if a VLA file is being written.

  Modified:

    26 May 1999

  Author:

    John Burkardt
*/
{
  int icor3;
  int iface;
  int ivert;
  int jcor3;
  int jvert;
/*
  Case 0:
  No line pruning.
*/
  if ( line_prune == 0 ) {

    for ( iface = 0; iface < face_num; iface++ ) {

      for ( ivert = 0; ivert < face_order[iface]; ivert++ ) {

        icor3 = face[ivert][iface];

        line_num = line_num + 1;
        if ( line_num <= LINES_MAX ) {
          line_dex[line_num] = icor3;
          line_material[line_num] = vertex_material[ivert][iface];
        }
      }

      ivert = 0;
      icor3 = face[ivert][iface];

      line_num = line_num + 1;
      if ( line_num <= LINES_MAX ) {
        line_dex[line_num] = icor3;
        line_material[line_num] = vertex_material[ivert][iface];
      }

      line_num = line_num + 1;
      if ( line_num <= LINES_MAX ) {
        line_dex[line_num] = -1;
        line_material[line_num] = -1;
      }
    }

  }
/*
  Case 2:
  Simple-minded line pruning.
  Only draw line (I,J) if I < J.
*/
  else {

    for ( iface = 0; iface < face_num; iface++ ) {

      for ( ivert = 0; ivert < face_order[iface]; ivert++ ) {

        icor3 = face[ivert][iface];

        if ( ivert + 1 < face_order[iface] ) {
          jvert = ivert + 1;
        }
        else {
          jvert = 0;
        }

        jcor3 = face[jvert][iface];
        
        if ( icor3 < jcor3 ) {

          if ( line_num + 3 < LINES_MAX ) {

            line_num = line_num + 1;
            line_dex[line_num] = icor3;
            line_material[line_num] = vertex_material[ivert][iface];

            line_num = line_num + 1;
            line_dex[line_num] = jcor3;
            line_material[line_num] = vertex_material[jvert][iface];

            line_num = line_num + 1;
            line_dex[line_num] = -1;
            line_material[line_num] = -1;

          }
        }
      }
    }

  }

  return;
}
/**********************************************************************/

void face_to_vertex_material ( void )

/**********************************************************************/

/*
  Purpose:

    FACE_TO_VERTEX_MAT extends face material definitions to vertices.

  Discussion:

    Assuming material indices are defined for all the faces, this
    routine assigns to each vertex of a face the material of that face.

  Modified:

    22 May 1999

  Author:

    John Burkardt
*/
{
  int iface;
  int ivert;

  for ( iface = 0; iface < face_num; iface++ ) {
    for ( ivert = 0; ivert < face_order[iface]; ivert++ ) {
      vertex_material[ivert][iface] = face_material[iface];
    }
  }

  return;
}
/******************************************************************************/

char *file_ext ( char *file_name )

/******************************************************************************/

/*
  Purpose:
   
    FILE_EXT picks out the extension in a file name.

  Modified:

    21 July 1998

  Author:
 
    John Burkardt
*/
{
  int i;

  i = char_index_last ( file_name, '.' );

  if ( i == -1 ) {
    return NULL;
  }
  else {
    return file_name + i + 1;
  }
}
/******************************************************************************/

float float_read ( FILE *filein )

/******************************************************************************/

/*
  Purpose:

    FLOAT_READ reads 1 float from a binary file.

  Modified:

    24 May 1999
*/
{
  float rval;
  float temp;

  fread ( &temp, sizeof ( float ), 1, filein );

  if ( byte_swap == TRUE ) {
    rval = float_reverse_bytes ( temp );
  }
  else {
    rval = temp;
  }

  return rval;
}
/******************************************************************************/

float float_reverse_bytes ( float x )

/******************************************************************************/

/*
  Purpose:

    FLOAT_REVERSE_BYTES reverses the four bytes in a float.

  Modified:

    24 May 1999

  Author:

    John Burkardt

  Parameters:

    X, a float whose bytes are to be reversed.

    FLOAT_REVERSE_BYTES, a float with bytes in reverse order from those in X.
*/
{
  char c;
  union {
    float yfloat;
    char ychar[4];
  } y;

  y.yfloat = x;
  
  c = y.ychar[0];
  y.ychar[0] = y.ychar[3];
  y.ychar[3] = c;

  c = y.ychar[1];
  y.ychar[1] = y.ychar[2];
  y.ychar[2] = c;

  return ( y.yfloat );
}
/******************************************************************************/

int float_write ( FILE *fileout, float float_val )

/******************************************************************************/

/*
  Purpose:

    FLOAT_WRITE writes 1 float to a binary file.

  Modified:

    23 September 1998
*/
{
  int nbyte = sizeof ( float );
  float temp;

  if ( byte_swap == TRUE ) {
    temp = float_reverse_bytes ( float_val );
  }
  else {
    temp = float_val;
  }

  fwrite ( &temp, nbyte, 1, fileout );

  return nbyte;
}
/******************************************************************************/

int gmod_arch_check ( void )

/******************************************************************************/

/*
  Purpose:
   
    GMOD_ARCH_CHECK inquires into some features of the computer architecture.

  Modified:

    19 May 1999

  Author:
 
    Zik Saleeba (zik@zikzak.net)
*/
{
  static unsigned char one[4];
  int temp;
  
  temp = sizeof ( float );
  if ( temp != 4 ) {
    return FALSE;
  }

  *(float *)one = 1.0;
  
  if (one[0] == 0 && one[1] == 0 && one[2] == 128 && one[3] == 63) {
    /* little endian IEEE floats */
    return TRUE;
  }
  
  if (one[0] == 63 && one[1] == 128 && one[2] == 0 && one[3] == 0) {
    /* big endian IEEE floats */
    return TRUE;
  }
  
  return FALSE;
}
/******************************************************************************/

int gmod_read ( FILE *filein )

/******************************************************************************/

/*
  Purpose:
   
    GMOD_READ reads a golgotha GMOD file.

  Modified:

    19 May 1999

  Author:
 
    Zik Saleeba (zik@zikzak.net)
*/

/*
golgotha GMOD file format:


        FILE HEADER

w32     magic number           f9 fa 63 1e
w32     number of sections
[ number of sections
    w32     section id
    w32     section offset
]


        TEXTURE NAME SECTION - section id = 0x13 (19)

w16     number of faces
[ number of faces
    w16     texture name length
    [ texture name length
        w8      texture name character
    ]
]



        MODEL QUADS SECTION - section id = 0x12 (18)

w16     number of faces
[ number of faces
    [ four vertices
        w16     vertex index
        float   xpos (0.0-1.0)
        float   ypos (0.0-1.0)
    ]
    float   scale
    w16     flags
    float   xnormal     (normal should be normalised)
    float   ynormal
    float   znormal
]


        VERTEX ARRAY SECTION - section id = 0x14 (20)

w16     number of vertices
w16     number of animations
w16     length of animation name
[ length of animation name
    w8      animation name character
]
w16     number of frames in animation
[ number of frames in animation
    [ number of vertices
        float   xpos
        float   ypos
        float   zpos
        float   xnormal
        float   ynormal
        float   znormal
    ]
]
*/
{
  unsigned char MagicNumber[4];
  unsigned long int NumSections;
  int SectionCount;
  unsigned long int SectionID[GMOD_MAX_SECTIONS];
  unsigned long int SectionOffset[GMOD_MAX_SECTIONS];
  
  unsigned short NumAnimations;
  unsigned short NumFrames;
  unsigned short FaceCount;
  unsigned short TextureCount;
  int VertexCount;
  
  float Scale;
  unsigned short Flags;
  unsigned short TextureNameLen;
  unsigned short AnimationNameLen;
  int Order;
  int MaxCor = 0;
  
  /*
   * check if we can handle this architecture
   */
   
  if (!gmod_arch_check()) {
    printf("GMOD_READ - This architecture not supported.\n");
    return ERROR;
  }
  
  /* 
   * read the file header 
   */
   
  /* read the magic number */
  fread(MagicNumber, 1, 4, filein);
  if (MagicNumber[0] != 0xf9 || 
      MagicNumber[1] != 0xfa || 
      MagicNumber[2] != 0x63 || 
      MagicNumber[3] != 0x1e) {
    printf("GMOD_READ - Bad magic number on GMOD file.\n");
    return ERROR;
  }
  
  NumSections = gmod_read_w32(filein);
  if (NumSections >= GMOD_MAX_SECTIONS) {
    printf("GMOD_READ - Too many sections (%ld) in GMOD file - please increase static limit GMOD_MAX_SECTIONS\n", NumSections);
    return ERROR;
  }
  
/* 
  Read the sections.
*/

  for ( SectionCount = 0; SectionCount < ( int ) NumSections; SectionCount++ ) {
    SectionID[SectionCount] = gmod_read_w32(filein);
    SectionOffset[SectionCount] = gmod_read_w32(filein);
  }
/* 
  Read each successive section.
*/
  for ( SectionCount = 0; SectionCount < ( int ) NumSections; SectionCount++ ) {
/* 
  Go to the start of the section.
*/
    fseek ( filein, ( long int ) SectionOffset[SectionCount], SEEK_SET );
/* 
  What type of section is it?
*/
    switch (SectionID[SectionCount]) {
    
/*
  Model section.
*/
      case G1_SECTION_MODEL_QUADS:
/* 
  Get the number of faces.
*/
        face_num = gmod_read_w16 ( filein );

        if (face_num > FACE_MAX) {
          printf("GMOD_READ - Too many faces (%d) in GMOD file - please increase static limit FACE_MAX.\n", face_num);
          return ERROR;
        }
/* 
  Get the information on each face.
*/
        for ( FaceCount = 0; FaceCount < ( unsigned short ) face_num; FaceCount++ ) {
        
          Order = 0;
          for ( VertexCount = 0; VertexCount < 4; VertexCount++ ) {
          
            /* read the vertex index */

            face[VertexCount][FaceCount] = gmod_read_w16(filein);

            if (face[VertexCount][FaceCount] != GMOD_UNUSED_VERTEX) {
              Order = VertexCount+1;
              if (MaxCor < face[VertexCount][FaceCount])
                MaxCor = face[VertexCount][FaceCount];
            }
            
            /* read the texture position */

            vertex_tex_uv[0][VertexCount][FaceCount] = gmod_read_float(filein);
            vertex_tex_uv[1][VertexCount][FaceCount] = gmod_read_float(filein);
          }
          
          /* scale and flags */

          fread(&Scale, sizeof(Scale), 1, filein);
          Flags = gmod_read_w16(filein);

          if ( debug ) {
            printf ( "Flags = %d\n", Flags );
          }
          
          /* normal vector */

          face_normal[0][FaceCount] = gmod_read_float(filein);
          face_normal[1][FaceCount] = gmod_read_float(filein);
          face_normal[2][FaceCount] = gmod_read_float(filein);
          
          /* the order is the number of used vertices */

          face_order[FaceCount] = Order;
        }
        break;
      
      
/*
  Texture name section.
*/
        
      case G1_SECTION_MODEL_TEXTURE_NAMES:
      
        /* get the number of textures */

        texture_num = gmod_read_w16(filein);
        if (texture_num > TEXTURE_MAX) {
          printf ( "GMOD_READ - Too many texture maps (%d) in GMOD file.\n", texture_num );
          printf ( "  Increase static limit TEXTURE_MAX.\n" );
          return ERROR;
        }
        face_num = texture_num;
        
        for (TextureCount = 0; TextureCount < ( unsigned short ) texture_num; 
          TextureCount++) {
          
          /* read the texture name */

          TextureNameLen = gmod_read_w16(filein);
          fread ( texture_name[TextureCount], sizeof(char), TextureNameLen, filein);
          texture_name[TextureCount][TextureNameLen] = '\0';
        }
        break;
       
    
      /*
       * vertex section
       */
        
      case G1_SECTION_MODEL_VERT_ANIMATION:
      
        /* get the number of vertices */

        cor3_num = gmod_read_w16(filein);
        if (cor3_num > COR3_MAX) {
          printf("GMOD_READ - Too many vertices (%d) in GMOD file - please increase static limit COR3_MAX.\n", cor3_num);
          return ERROR;
        }
      
/* 
  Get the number of animations.
*/

        NumAnimations = gmod_read_w16(filein);

        if (NumAnimations > 1) {
          printf ( "GMOD_READ - Fatal error!\n" );
          printf ( "  GMOD files can only handle one animation.\n" );
          printf ( "  This file contains %d.\n", NumAnimations );
          return ERROR;
        }
        
        /* read the animation name */
        AnimationNameLen = gmod_read_w16(filein);
        fread ( anim_name, sizeof(char), AnimationNameLen, filein);
        anim_name[AnimationNameLen] = '\0';
        
        /* get the number of frames of animation */
        NumFrames = gmod_read_w16(filein);
        if (NumFrames > 1)
          printf("GMOD_READ - Too many frames of animation (%d) in GMOD file - will only use 1.\n", NumFrames);
        
        /* go through all the vertices, reading each one */
        for (VertexCount = 0; VertexCount < cor3_num; VertexCount++) {
          
          /* read the vertex */
          cor3[0][VertexCount] = gmod_read_float(filein);
          cor3[1][VertexCount] = gmod_read_float(filein);
          cor3[2][VertexCount] = gmod_read_float(filein);
          
          /* read the normal */
          cor3_normal[0][VertexCount] = gmod_read_float(filein);
          cor3_normal[1][VertexCount] = gmod_read_float(filein);
          cor3_normal[2][VertexCount] = gmod_read_float(filein);
        }
        break;
        
      default:
        continue;
    }
  }
  
/* 
  Set some other stray info.
*/
  line_num = 0;
  
/* 
  Check for sanity.
*/
  if ( MaxCor >= cor3_num ) {
    printf ( "GMOD_READ - Maximum coordinate index (%d)\n", MaxCor );
    printf ( "  exceeded number of coordinates (%d) in GMOD file.\n", cor3_num );
    return ERROR;
  }

  return SUCCESS;
}
/******************************************************************************/

float gmod_read_float ( FILE *filein )

/******************************************************************************/

/*
  Purpose:
   
    GMOD_READ_FLOAT reads a float from a Golgotha GMOD file.

  Modified:

    19 May 1999

  Author:
 
    Zik Saleeba (zik@zikzak.net)
*/
{
  int endian = 1;
  unsigned char *out_pos;
  int i;
  float Val;

  if (*(char *)&endian == 1) {
    /* we're little-endian, which is native for GMOD floats */
    fread(&Val, sizeof(Val), 1, filein);
  }
  else {
    /* we're big-endian, flip `em */
    out_pos = (unsigned char *)&Val;
    for ( i = sizeof(Val)-1; i >= 0; i-- ) {
      *(out_pos+i) = fgetc(filein);
    }
  }
  
  return Val;
}
/******************************************************************************/

unsigned short gmod_read_w16 ( FILE *filein )

/******************************************************************************/

/*
  Purpose:
   
    GMOD_READ_W16 reads a 16 bit word from a Golgotha GMOD file.

  Modified:

    19 May 1999

  Author:
 
    Zik Saleeba (zik@zikzak.net)
*/
{
  unsigned char Byte1;
  unsigned char Byte2;
  
  Byte1 = fgetc ( filein );
  Byte2 = fgetc ( filein );
  
  return Byte1 | (((unsigned short)Byte2) << 8);
}
/******************************************************************************/

unsigned long gmod_read_w32 ( FILE *filein )

/******************************************************************************/

/*
  Purpose:
   
    GMOD_READ_W32 reads a 32 bit word from a Golgotha GMOD file.

  Modified:

    19 May 1999

  Author:
 
    Zik Saleeba (zik@zikzak.net)
*/
{
  unsigned char Byte1, Byte2, Byte3, Byte4;
  
  Byte1 = fgetc(filein);
  Byte2 = fgetc(filein);
  Byte3 = fgetc(filein);
  Byte4 = fgetc(filein);
  
  return Byte1 | 
         (((unsigned long)Byte2) << 8) | 
         (((unsigned long)Byte3) << 16) | 
         (((unsigned long)Byte4) << 24);
}

/******************************************************************************/

int gmod_write ( FILE *fileout ) {

/******************************************************************************/

/*
  Purpose:
   
    GMOD_WRITE writes a Golgotha GMOD file.

  Modified:

    19 May 1999

  Author:
 
    Zik Saleeba (zik@zikzak.net)
*/
  static unsigned char MagicNumber[4] = { 0xf9, 0xfa, 0x63, 0x1e };
  unsigned long NumSections;
  unsigned long SectionHeaderPos;
  unsigned long TextureNameSectionPos;
  unsigned long ModelSectionPos;
  unsigned long VertexSectionPos;
  
  int VertexCount;
  int FaceCount;
  int TextureCount;
  unsigned long SectionCount;
  float Scale;  
  float Min[3];
  float Max[3];
  int CorNumber;
  int DimensionCount;
  float MaxWidth;
/*
  Check if we can handle this architecture.
*/
   
  if ( !gmod_arch_check() ) {
    printf("GMOD_WRITE - This architecture not supported.\n");
    return ERROR;
  }
  
/* 
  Write the file header.
*/
   
/* 
  Write the magic number.
*/
  fwrite ( MagicNumber, sizeof(char), 4, fileout );

/* 
  Write the number of sections.
*/ 
  NumSections = 3;
  gmod_write_w32 ( NumSections, fileout ); 
  
/* 
  Write a dummy section header which we'll overwrite later.
*/
  SectionHeaderPos = ftell ( fileout );
  for (SectionCount = 0; SectionCount < NumSections; SectionCount++) {
    gmod_write_w32 ( 0, fileout );
    gmod_write_w32 ( 0, fileout );
  }  
/*
  Texture name section.
*/
  
/* 
  Take note of where we are in the file.
*/
  TextureNameSectionPos = ftell ( fileout );

/* 
  Write the number of textures.
*/

  gmod_write_w16 ( ( unsigned short ) face_num, fileout );
/*
  Write the texture names.
*/
  for ( TextureCount = 0; TextureCount < face_num; TextureCount++ ) {

    gmod_write_w16 ( ( unsigned short ) strlen ( texture_name[TextureCount] ), 
      fileout );

    fwrite ( texture_name[TextureCount], strlen ( texture_name[TextureCount] ), 
      1, fileout );
  }

/*
  Model section.
*/

/* 
  Take note of where we are in the file.
*/

  ModelSectionPos = ftell(fileout);

/* 
  Write the number of faces.
*/

  gmod_write_w16 ( ( unsigned short ) face_num, fileout );

/* 
  Write the information on each face.
*/

  for ( FaceCount = 0; FaceCount < face_num; FaceCount++ ) {

    for (VertexCount = 0; VertexCount < ((face_order[FaceCount] < 4) ? face_order[FaceCount] : 4); VertexCount++) {

/* 
  Write the vertex index.
*/
      gmod_write_w16 ( ( unsigned short ) face[VertexCount][FaceCount], fileout );

/* 
  Write the texture position.
*/

      gmod_write_float ( vertex_tex_uv[0][VertexCount][FaceCount], fileout );
      gmod_write_float ( vertex_tex_uv[1][VertexCount][FaceCount], fileout );
    }
    
/* 
  Write any extra vertices which are unused.
*/

    for ( ; VertexCount < 4; VertexCount++ ) {
    
/* 
  Write the vertex index.
*/
      gmod_write_w16 ( GMOD_UNUSED_VERTEX, fileout );
/* 
  Write the texture position.
*/
      gmod_write_float ( vertex_tex_uv[0][VertexCount][FaceCount], fileout );

      gmod_write_float ( vertex_tex_uv[1][VertexCount][FaceCount], fileout );
    }

/*
  Scale and flags.
*/
    
/* 
  Find the bounding box.
*/

    for ( DimensionCount = 0; DimensionCount < 3; DimensionCount++ ) {
      
      CorNumber = face[0][FaceCount];
      Min[DimensionCount] = cor3[DimensionCount][CorNumber];
      Max[DimensionCount] = cor3[DimensionCount][CorNumber];
      
      for (VertexCount = 1; VertexCount < ((face_order[FaceCount] < 4) ? face_order[FaceCount] : 4); VertexCount++) {

        CorNumber = face[VertexCount][FaceCount];
        
        if (Min[DimensionCount] > cor3[DimensionCount][CorNumber])
          Min[DimensionCount] = cor3[DimensionCount][CorNumber];
         
        if (Max[DimensionCount] < cor3[DimensionCount][CorNumber])
          Max[DimensionCount] = cor3[DimensionCount][CorNumber];
      }
    }
    
/* 
  The scale is the "width" of the face for mipmapping - 
  I just take the maximum bounding box dimension.
*/
    MaxWidth = Max[0] - Min[0];
    for ( DimensionCount = 1; DimensionCount < 3; DimensionCount++ ) {
    
       if ( MaxWidth < Max[DimensionCount] - Min[DimensionCount] )
           MaxWidth = Max[DimensionCount] - Min[DimensionCount];
    }

    Scale = MaxWidth;
    fwrite ( &Scale, sizeof(Scale), 1, fileout );
    
/* 
  Flags are just nothing.
*/
    gmod_write_w16 ( 0, fileout );
/* 
  Normal vector.
*/
    gmod_write_float ( face_normal[0][FaceCount], fileout );
    gmod_write_float ( face_normal[1][FaceCount], fileout );
    gmod_write_float ( face_normal[2][FaceCount], fileout );
  }

/*
  Vertex section.
*/

/* 
  Take note of where we are in the file.
*/

  VertexSectionPos = ftell ( fileout );

/* 
  Write the number of vertices.
*/

  gmod_write_w16 ( ( unsigned short ) cor3_num, fileout );

/* 
  Write the number of animations.
*/

  gmod_write_w16 ( 1, fileout );

/* 
  Write the animation name. 
*/

  gmod_write_w16 ( 0, fileout );

/* 
  Write the number of frames of animation.
*/

  gmod_write_w16 ( 1, fileout );

/* 
  Go through all the vertices, writing each one.
*/

  for ( VertexCount = 0; VertexCount < cor3_num; VertexCount++ ) {

/* 
  Write the vertex.
*/
    gmod_write_float ( cor3[0][VertexCount], fileout );
    gmod_write_float ( cor3[1][VertexCount], fileout );
    gmod_write_float ( cor3[2][VertexCount], fileout );

/* 
  Write the normal.
*/
    gmod_write_float ( cor3_normal[0][VertexCount], fileout );
    gmod_write_float ( cor3_normal[1][VertexCount], fileout );
    gmod_write_float ( cor3_normal[2][VertexCount], fileout );
  }
/*
  Now rewrite the section header.
*/
   
/* 
  Go back to the section header.
*/
  fseek ( fileout, ( long int ) SectionHeaderPos, SEEK_SET );
  
/* 
  Write the texture name section header.
*/
  gmod_write_w32 ( G1_SECTION_MODEL_TEXTURE_NAMES, fileout );
  gmod_write_w32 ( TextureNameSectionPos, fileout );

/* 
  Write the model section header.
*/
  gmod_write_w32 ( G1_SECTION_MODEL_QUADS, fileout );
  gmod_write_w32 ( ModelSectionPos, fileout );

/* 
  Write the vertex section header.
*/
  gmod_write_w32 ( G1_SECTION_MODEL_VERT_ANIMATION, fileout );
  gmod_write_w32 ( VertexSectionPos, fileout );

  return SUCCESS;
}

/******************************************************************************/

void gmod_write_float ( float Val, FILE *fileout )

/******************************************************************************/

/*
  Purpose:
   
    GMOD_WRITE_FLOAT writes a float to a Golgotha GMOD file.

  Modified:

    19 May 1999

  Author:
 
    Zik Saleeba (zik@zikzak.net)
*/
{
  int endian = 1;
  unsigned char *out_pos;
  int i;

  if (*(char *)&endian == 1) {
    /* we're little-endian, which is native for GMOD floats */
    fwrite ( &Val, sizeof(Val), 1, fileout );
  }
  else {
    /* we're big-endian, flip `em */
    out_pos = (unsigned char *)&Val;
    for ( i = sizeof(Val)-1; i >= 0; i-- ) {
      fputc(*(out_pos+i), fileout);
    }
  }
}
/******************************************************************************/

void gmod_write_w16 ( unsigned short Val, FILE *fileout )

/******************************************************************************/

/*
  Purpose:
   
    GMOD_WRITE_W16 writes a 16 bit word to a Golgotha GMOD file.

  Modified:

    13 September 2000

  Author:
 
    Zik Saleeba (zik@zikzak.net)
*/
{
  unsigned char OutByte[2];
  
  OutByte[0] = (unsigned char)(Val & 0xff);
  OutByte[1] = (unsigned char)(Val >> 8);
  
  fwrite ( OutByte, sizeof(unsigned char), 2, fileout );
}
/******************************************************************************/

void gmod_write_w32 ( unsigned long Val, FILE *fileout )

/******************************************************************************/

/*
  Purpose:
   
    GMOD_WRITE writes a 32 bit word to a Golgotha GMOD file.

  Modified:

    19 May 1999

  Author:
 
    Zik Saleeba (zik@zikzak.net)
*/
{
  unsigned char OutByte[4];
  
  OutByte[0] = (unsigned char)(Val & 0xff);
  OutByte[1] = (unsigned char)((Val >> 8) & 0xff);
  OutByte[2] = (unsigned char)((Val >> 16) & 0xff);
  OutByte[3] = (unsigned char)((Val >> 24) & 0xff);
  
  fwrite ( OutByte, sizeof(unsigned char), 4, fileout );
}

/******************************************************************************/

void hello ( void )

/******************************************************************************/
/*
  Purpose:

    HELLO prints an explanatory header message.

  Modified:

    04 July 2000

  Author:
 
    John Burkardt
*/
{
  printf ( "\n" );
  printf ( "Hello:  This is IVCON,\n" );
  printf ( "  for 3D graphics file conversion.\n" );
  printf ( "\n" );
  printf ( "    \".3ds\"   3D Studio Max binary;\n" );
  printf ( "    \".ase\"   3D Studio Max ASCII export;\n" );
  printf ( "    \".byu\"   Movie.BYU surface geometry;\n" );
  printf ( "    \".dxf\"   DXF;\n" );
  printf ( "    \".gmod\"  Golgotha model;\n" );
  printf ( "    \".hrc\"   SoftImage hierarchy;\n" );
  printf ( "    \".iv\"    SGI Open Inventor;\n" );
  printf ( "    \".obj\"   WaveFront Advanced Visualizer;\n" );
  printf ( "    \".pov\"   Persistence of Vision (output only);\n" );
  printf ( "    \".smf\"   Michael Garland's format;\n" );
  printf ( "    \".stl\"   ASCII StereoLithography;\n" );
  printf ( "    \".stla\"  ASCII StereoLithography;\n" );
  printf ( "    \".stlb\"  Binary StereoLithography;\n" );
  printf ( "    \".tec\"   TECPLOT (output only);\n" );
  printf ( "    \".tri\"   [Greg Hood ASCII triangle format];\n" );
  printf ( "    \".tria\"  [Greg Hood ASCII triangle format];\n" );
  printf ( "    \".trib\"  [Greg Hood binary triangle format];\n" );
  printf ( "    \".txt\"   Text (output only);\n" );
  printf ( "    \".ucd\"   AVS UCD file(output only);\n" );
  printf ( "    \".vla\"   VLA;\n" );
  printf ( "    \".wrl\"   VRML (Virtual Reality Modeling Language) (output only).\n" );
  printf ( "    \".xgl\"   XML/OpenGL format (output only);\n" );
  printf ( "\n" );
  printf ( "  Current limits include:\n" );
  printf ( "    %d faces;\n", FACE_MAX );
  printf ( "    %d line items;\n", LINES_MAX );
  printf ( "    %d points;\n", COR3_MAX );
  printf ( "    %d face order;\n", ORDER_MAX );
  printf ( "    %d materials;\n", MATERIAL_MAX);
  printf ( "    %d textures.\n", TEXTURE_MAX );
  printf ( "\n" );
  printf ( "  Last modification: 04 July 2000.\n" );
  printf ( "\n" );
  printf ( "  Send problem reports to burkardt@psc.edu.\n" );
 
  return;
}
/******************************************************************************/

void help ( void )

/******************************************************************************/

/*
  Purpose:

    HELP prints a list of the interactive commands.

  Modified:

    26 May 1999

  Author:
 
    John Burkardt
*/
{
  printf ( "\n" );
  printf ( "Commands:\n" );
  printf ( "\n" );
  printf ( "< file   Read data from input file;\n" );
  printf ( "<< file  Append data in input file to current data;\n" );
  printf ( "> file   Write output file;\n" );
  printf ( "B        Switch the binary file byte-swapping mode;\n" );
  printf ( "D        Switch the debugging mode;\n" );
  printf ( "F        Print information about one face;\n" );
  printf ( "H        Print this help list;\n" );
  printf ( "I        Info, print out recent changes;\n" );
  printf ( "LINES    Convert face information to lines;\n" );
  printf ( "N        Recompute normal vectors;\n" );
  printf ( "P        Set LINE_PRUNE option.\n" );
  printf ( "Q        Quit;\n" );
  printf ( "R        Reverse the normal vectors.\n" );
  printf ( "S        Select face subset (NOT WORKING).\n" );
  printf ( "T        Transform the data.\n" );
  printf ( "W        Reverse the face node ordering.\n" );

  return;
}
/******************************************************************************/

int hrc_read ( FILE *filein )

/******************************************************************************/

/*
  Purpose:

    HRC_READ reads graphics information from a SoftImage HRC file.

  Examples:

    HRCH: Softimage 4D Creative Environment v3.00


    model
    {
      name         "cube_10x10"
      scaling      1.000 1.000 1.000
      rotation     0.000 0.000 0.000
      translation  0.000 0.000 0.000

      mesh
      {
        flag    ( PROCESS )
        discontinuity  60.000

        vertices   8
        {
          [0] position  -5.000  -5.000  -5.000
          [1] position  -5.000  -5.000  5.000
          [2] position  -5.000  5.000  -5.000
          [3] position  -5.000  5.000  5.000
          [4] position  5.000  -5.000  -5.000
          [5] position  5.000  -5.000  5.000
          [6] position  5.000  5.000  -5.000
          [7] position  5.000  5.000  5.000
        }

        polygons   6
        {
          [0] nodes  4
              {
                [0] vertex  0
                    normal  -1.000  0.000  0.000
                    uvTexture  0.000  0.000
                    vertexColor 255 178 178 178
                [1] vertex  1
                    normal  -1.000  0.000  0.000
                    uvTexture  0.000  0.000
                    vertexColor 255 178 178 178
                [2] vertex  3
                    normal  -1.000  0.000  0.000
                    uvTexture  0.000  0.000
                    vertexColor 255 178 178 178
                [3] vertex  2
                    normal  -1.000  0.000  0.000
                    uvTexture  0.000  0.000
                    vertexColor 255 178 178 178
              }
              material  0
          [1] nodes  4
             {
                [0] vertex  1
                    normal  0.000  0.000  1.000
                    uvTexture  0.000  0.000
                    vertexColor 255 178 178 178
                [1] vertex  5

    ...etc.....

          [5] nodes  4
              {
                [0] vertex  2
                    normal  0.000  1.000  0.000
                    uvTexture  0.000  0.000
                    vertexColor 255 178 178 178
                [1] vertex  3
                    normal  0.000  1.000  0.000
                    uvTexture  0.000  0.000
                    vertexColor 255 178 178 178
                [2] vertex  7
                    normal  0.000  1.000  0.000
                    uvTexture  0.000  0.000
                    vertexColor 255 178 178 178
                [3] vertex  6
                    normal  0.000  1.000  0.000
                    uvTexture  0.000  0.000
                    vertexColor 255 178 178 178
              }
              material  0
        }

        edges   12
        {
          [1] vertices  3  2
          [2] vertices  2  0
          [3] vertices  0  1
          [4] vertices  1  3
          [5] vertices  7  3
          [6] vertices  1  5
          [7] vertices  5  7
          [8] vertices  6  7
          [9] vertices  5  4
          [10] vertices  4  6
          [11] vertices  2  6
          [12] vertices  4  0
        }
      }

      material [0]
      {
      name           "kazoo"
      type           PHONG
      ambient        0.0  1.0  0.0
      diffuse        1.0  0.0  0.0
      specular       0.0  0.0  1.0
      exponent      50.0
      reflectivity   0.0
      transparency   0.0
      refracIndex    1.0
      glow           0
      coc            0.0
      }

      texture [0]
      {
      name          "/usr/users/foss/HOUSE/PICTURES/mellon"
      glbname       "t2d1"
      anim          STATIC
      method        XY
      repeat        1  1
      scaling       1.000  1.000
      offset        0.000  0.000
      pixelInterp
      effect        INTENSITY
      blending      1.000
      ambient       0.977
      diffuse       1.000
      specular      0.966
      reflect       0.000
      transp        0.000
      roughness     0.000
      reflMap       1.000
      rotation      0.000
      txtsup_rot    0.000  0.000  0.000
      txtsup_trans  0.000  0.000  0.000
      txtsup_scal   1.000  1.000  1.000
      }
    }

  Modified:

    25 June 1999

  Author:

    John Burkardt
*/
{
  float b;
  int   count;
  float g;
  int   i;
  int   icor3;
  int   ivert;
  int   iword;
  int   jval;
  int   level;
  char *next;
  int   nlbrack;
  int   nrbrack;
  int   cor3_num_old;
  float r;
  float t;
  float temp[3];
  int   width;
  char  word[LINE_MAX_LEN];
  char  word1[LINE_MAX_LEN];
  char  word2[LINE_MAX_LEN];
  char  wordm1[LINE_MAX_LEN];
  float x;
  float y;
  float z;

  level = 0;
  strcpy ( level_name[0], "Top" );
  nlbrack = 0;
  nrbrack = 0;
  cor3_num_old = cor3_num;
  strcpy ( word, " " );
  strcpy ( wordm1, " " );
/*
  Read a line of text from the file.
*/
  for ( ;; ) {

    if ( fgets ( input, LINE_MAX_LEN, filein ) == NULL ) {
      break;
    }

    text_num = text_num + 1;
    next = input;
    iword = 0;
/*
  Read a word from the line.
*/
    for ( ;; ) {

      strcpy ( wordm1, word );

      count = sscanf ( next, "%s%n", word2, &width );
      next = next + width;

      if ( count <= 0 ) {
        break;
      }

      strcpy ( word, word2 );

      iword = iword + 1;

      if ( iword == 1 ) {
        strcpy ( word1, word );
      }
/*
  The first line of the file must be the header.
*/
      if ( text_num == 1 ) {

        if ( strcmp ( word1, "HRCH:" ) != 0 ) {
          printf ( "\n" );
          printf ( "HRC_READ - Fatal error!\n" );
          printf ( "  The input file has a bad header.\n" );
          return ERROR;
        }
        else {
          comment_num = comment_num + 1;
        }
        break;
      }
/*
  If the word is a curly bracket, count it.
*/
      if ( strcmp ( word, "{" ) == 0 ) {
        nlbrack = nlbrack + 1;
        level = nlbrack - nrbrack;
        strcpy ( level_name[level], wordm1 );
        if ( debug ) {
          printf ( "New level: %s\n", level_name[level] );
        }
      }
      else if ( strcmp ( word, "}" ) == 0 ) {
        nrbrack = nrbrack + 1;

        if ( nlbrack < nrbrack ) {
          printf ( "\n" );
          printf ( "HRC_READ - Fatal error!\n" );
          printf ( "  Extraneous right bracket on line %d.\n", text_num );
          printf ( "  Currently processing field %s\n.", level_name[level] );
          return ERROR;
        }
      }
/*
  CONTROLPOINTS
*/
      if ( strcmp ( level_name[level], "controlpoints" ) == 0 ) {

        if ( strcmp ( word, "{" ) == 0 ) {
        }
        else if ( strcmp ( word, "}" ) == 0 ) {

          if ( line_num < LINES_MAX ) {
            line_dex[line_num] = -1;
            line_material[line_num] = 0;
          }
          line_num = line_num + 1;
          level = nlbrack - nrbrack;
        }
        else if ( word[0] == '[' ) {
        }
        else if ( strcmp ( word, "position" ) == 0 ) {

          count = sscanf ( next, "%f%n", &x, &width );
          next = next + width;

          count = sscanf ( next, "%f%n", &y, &width );
          next = next + width;

          count = sscanf ( next, "%f%n", &z, &width );
          next = next + width;

          temp[0] = x;
          temp[1] = y;
          temp[2] = z;

          if ( cor3_num < 1000 ) {
            icor3 = rcol_find ( cor3, 3, cor3_num, temp );
          }
          else {
            icor3 = -1;
          }

          if ( icor3 == -1 ) {

            icor3 = cor3_num;
            if ( cor3_num < COR3_MAX ) {
              cor3[0][cor3_num] = x;
              cor3[1][cor3_num] = y;
              cor3[2][cor3_num] = z;
            }
            cor3_num = cor3_num + 1;

          }
          else {
            dup_num = dup_num + 1;
          }

          if ( line_num < LINES_MAX ) {
            line_dex[line_num] = icor3;
            line_material[line_num] = 0;
          }
          line_num = line_num + 1;
        }
        else {
          bad_num = bad_num + 1;
          printf ( "CONTROLPOINTS: Bad data %s\n", word );
          return ERROR;
        }

      }
/*
  EDGES
*/
      else if ( strcmp ( level_name[level], "edges" ) == 0 ) {

        if ( strcmp( word, "{" ) == 0 ) {
        }
        else if ( strcmp ( word, "}" ) == 0 ) {
          level = nlbrack - nrbrack;
        }
        else if ( word[0] == '[' ) {
        }
        else if ( strcmp ( word, "vertices" ) == 0 ) {

          count = sscanf ( next, "%d%n", &jval, &width );
          next = next + width;

          if ( line_num < LINES_MAX ) {
            line_dex[line_num] = jval + cor3_num_old;
            line_material[line_num] = 0;
          }
          line_num = line_num + 1;

          count = sscanf ( next, "%d%n", &jval, &width );
          next = next + width;

          if ( line_num < LINES_MAX ) {
            line_dex[line_num] = jval + cor3_num_old;
            line_material[line_num] = 0;
          }
          line_num = line_num + 1;

          if ( line_num < LINES_MAX ) {
            line_dex[line_num] = -1;
            line_material[line_num] = -1;
          }
          line_num = line_num + 1;

        }
        else {
          bad_num = bad_num + 1;
          printf ( "EDGES: Bad data %s\n", word );
          return ERROR;
        }

      }
/*
  MATERIAL
*/
      else if ( strcmp ( level_name[level], "material" ) == 0 ) {

        if ( strcmp ( word, "{" ) == 0 ) {
          material_num = material_num + 1;
        }
        else if ( strcmp ( word, "}" ) == 0 ) {
          level = nlbrack - nrbrack;
        }
        else if ( word[0] == '[' ) {
        }
        else if ( strcmp ( word, "ambient" ) == 0 ) {
        }
        else if ( strcmp ( word, "coc" ) == 0 ) {
        }
        else if ( strcmp ( word, "diffuse" ) == 0 ) {

          count = sscanf ( next, "%f%n", &r, &width );
          next = next + width;
          material_rgba[0][material_num-1] = r;

          count = sscanf ( next, "%f%n", &g, &width );
          next = next + width;
          material_rgba[0][material_num-1] = g;

          count = sscanf ( next, "%f%n", &b, &width );
          next = next + width;
          material_rgba[0][material_num-1] = b;

        }
        else if ( strcmp ( word, "exponent" ) == 0 ) {
        }
        else if ( strcmp ( word, "glow" ) == 0 ) {
        }
        else if ( strcmp ( word, "name" ) == 0 ) {
          count = sscanf ( next, "%s%n", word, &width );
          next = next + width;
          strcpy ( material_name[material_num-1], word );
        }
        else if ( strcmp ( word, "reflectivity" ) == 0 ) {
        }
        else if ( strcmp ( word, "refracindex" ) == 0 ) {
        }
        else if ( strcmp ( word, "specular" ) == 0 ) {
        }
        else if ( strcmp ( word, "transparency" ) == 0 ) {
          count = sscanf ( next, "%f%n", &t, &width );
          next = next + width;
          material_rgba[3][material_num-1] = 1.0 - t;
        }
        else if ( strcmp ( word, "type" ) == 0 ) {
        }
        else {
          bad_num = bad_num + 1;
          printf ( "MATERIAL: Bad data %s\n", word );
          return ERROR;
        }
      }
/*
  MESH
*/
      else if ( strcmp ( level_name[level], "mesh" ) == 0 ) {

        if ( strcmp ( word, "{" ) == 0 ) {
        }
        else if ( strcmp ( word, "}" ) == 0 ) {
          level = nlbrack - nrbrack;
        }
        else if ( strcmp ( word, "discontinuity" ) == 0 ) {
          break;
        }
        else if ( strcmp ( word, "edges" ) == 0 ) {
          break;
        }
        else if ( strcmp ( word, "flag" ) == 0 ) {
          break;
        }
        else if ( strcmp ( word, "polygons" ) == 0 ) {
          break;
        }
        else if ( strcmp ( word, "vertices" ) == 0 ) {
          break;
        }
        else {
          bad_num = bad_num + 1;
          printf ( "MESH: Bad data %s\n", word );
          return ERROR;
        }

      }
/*
  MODEL
*/
      else if ( strcmp ( level_name[level], "model" ) == 0 ) {

        if ( strcmp ( word, "{" ) == 0 ) {
        }
        else if ( strcmp ( word, "}" ) == 0 ) {
          level = nlbrack - nrbrack;
        }
        else if ( strcmp ( word, "material" ) == 0 ) {
          break;
        }
        else if ( strcmp ( word, "mesh" ) == 0 ) {
          break;
        }
        else if ( strcmp ( word, "name" ) == 0 ) {
          break;
        }
        else if ( strcmp ( word, "patch" ) == 0 ) {
          break;
        }
        else if ( strcmp ( word, "rotation" ) == 0 ) {
          break;
        }
        else if ( strcmp ( word, "scaling" ) == 0 ) {
          break;
        }
        else if ( strcmp ( word, "spline" ) == 0 ) {
          break;
        }
        else if ( strcmp ( word, "translation" ) == 0 ) {
          break;
        }
        else {
          bad_num = bad_num + 1;
          printf ( "MODEL: Bad data %s\n", word );
          return ERROR;
        }

      }
/*
  NODES
*/
      else if ( strcmp ( level_name[level], "nodes" ) == 0 ) {

        if ( strcmp ( word, "{" ) == 0 ) {
          ivert = 0;
          face_order[face_num] = 0;
          face_num = face_num + 1;
        }
        else if ( strcmp ( word, "}" ) == 0 ) {
          level = nlbrack - nrbrack;
        }
        else if ( word[0] == '[' ) {
        }
        else if ( strcmp ( word, "normal" ) == 0 ) {

          count = sscanf ( next, "%f%n", &x, &width );
          next = next + width;

          count = sscanf ( next, "%f%n", &y, &width );
          next = next + width;

          count = sscanf ( next, "%f%n", &z, &width );
          next = next + width;

          if ( ivert < ORDER_MAX && face_num < FACE_MAX ) {
            vertex_normal[0][ivert-1][face_num-1] = x;
            vertex_normal[1][ivert-1][face_num-1] = y;
            vertex_normal[2][ivert-1][face_num-1] = z;
          }

        }
        else if ( strcmp ( word, "uvTexture" ) == 0 ) {

          count = sscanf ( next, "%f%n", &x, &width );
          next = next + width;

          count = sscanf ( next, "%f%n", &y, &width );
          next = next + width;

          if ( ivert < ORDER_MAX && face_num < FACE_MAX ) {
            vertex_tex_uv[0][ivert-1][face_num-1] = x;
            vertex_tex_uv[1][ivert-1][face_num-1] = y;
          }
        }
        else if ( strcmp ( word, "vertex" ) == 0 ) {

          count = sscanf ( next, "%d%n", &jval, &width );
          next = next + width;

          if ( ivert < ORDER_MAX && face_num < FACE_MAX ) {
            face_order[face_num-1] = face_order[face_num-1] + 1;
            face[ivert][face_num-1] = jval;
          }
          ivert = ivert + 1;

        }
/*
  Right now, we don't do anything with the vertexColor information.
*/
        else if ( strcmp ( word, "vertexColor" ) == 0 ) {

          count = sscanf ( next, "%d%n", &jval, &width );
          next = next + width;

          count = sscanf ( next, "%d%n", &jval, &width );
          next = next + width;

          count = sscanf ( next, "%d%n", &jval, &width );
          next = next + width;

          count = sscanf ( next, "%d%n", &jval, &width );
          next = next + width;
        }
        else {
          bad_num = bad_num + 1;
          printf ( "NODES: Bad data %s\n", word );
          return ERROR;
        }

      }
/*
  PATCH
  I don't know what to do with this yet.
*/
      else if ( strcmp ( level_name[level], "patch" ) == 0 ) {

        if ( strcmp ( word, "{" ) == 0 ) {
        }
        else if ( strcmp ( word, "}" ) == 0 ) {
          level = nlbrack - nrbrack;
        }
        else if ( strcmp ( word, "approx_type" ) == 0 ) {
        }
        else if ( strcmp ( word, "controlpoints" ) == 0 ) {
        }
        else if ( strcmp ( word, "curv_u" ) == 0 ) {
        }
        else if ( strcmp ( word, "curv_v" ) == 0 ) {
        }
        else if ( strcmp ( word, "recmin" ) == 0 ) {
        }
        else if ( strcmp ( word, "recmax" ) == 0 ) {
        }
        else if ( strcmp ( word, "recursion" ) == 0 ) {
        }
        else if ( strcmp ( word, "spacial" ) == 0 ) {
        }
        else if ( strcmp ( word, "taggedpoints" ) == 0 ) {
        }
        else if ( strcmp ( word, "ucurve" ) == 0 ) {
        }
        else if ( strcmp ( word, "ustep" ) == 0 ) {
        }
        else if ( strcmp ( word, "utension" ) == 0 ) {
        }
        else if ( strcmp ( word, "utype" ) == 0 ) {
        }
        else if ( strcmp ( word, "vclose" ) == 0 ) {
        }
        else if ( strcmp ( word, "vcurve" ) == 0 ) {
        }
        else if ( strcmp ( word, "viewdep" ) == 0 ) {
        }
        else if ( strcmp ( word, "vpoint" ) == 0 ) {
        }
        else if ( strcmp ( word, "vstep" ) == 0 ) {
        }
        else if ( strcmp ( word, "vtension" ) == 0 ) {
        }
        else if ( strcmp ( word, "vtype" ) == 0 ) {
        }
        else {
          bad_num = bad_num + 1;
          printf ( "PATCH: Bad data %s\n", word );
          return ERROR;
        }
      }
/*
  POLYGONS
*/
      else if ( strcmp ( level_name[level], "polygons" ) == 0 ) {

        if ( strcmp ( word, "{" ) == 0 ) {
        }
        else if ( strcmp ( word, "}" ) == 0 ) {
          level = nlbrack - nrbrack;
        }
        else if ( word[0] == '[' ) {
        }
        else if ( strcmp ( word, "material" ) == 0 ) {

          count = sscanf ( next, "%d%n", &jval, &width );
          next = next + width;

          for ( ivert = 0; ivert < ORDER_MAX; ivert++ ) {
            vertex_material[ivert][face_num-1] = jval;
          }

        }
        else if ( strcmp ( word, "nodes" ) == 0 ) {
          count = sscanf ( next, "%s%n", word2, &width );
          next = next + width;
        }
        else {
          bad_num = bad_num + 1;
          printf ( "POLYGONS: Bad data %s\n", word );
          return ERROR;
        }

      }
/*
  SPLINE
*/
      else if ( strcmp ( level_name[level], "spline" ) == 0 ) {

        if ( strcmp ( word, "{" ) == 0 ) {
        }
        else if ( strcmp ( word, "}" ) == 0 ) {
          level = nlbrack - nrbrack;
        }
        else if ( strcmp ( word, "controlpoints" ) == 0 ) {
          break;
        }
/*
  WHY DON'T YOU READ IN THE OBJECT NAME HERE?
*/
        else if ( strcmp ( word, "name" ) == 0 ) {
          break;
        }
        else if ( strcmp ( word, "nbKeys" ) == 0 ) {
          break;
        }
        else if ( strcmp ( word, "step" ) == 0 ) {
          break;
        }
        else if ( strcmp ( word, "tension" ) == 0 ) {
          break;
        }
        else if ( strcmp ( word, "type" ) == 0 ) {
          break;
        }
        else {
          bad_num = bad_num + 1;
          printf ( "SPLINE: Bad data %s\n", word );
          return ERROR;
        }

      }
/*
  TAGGEDPOINTS
*/
      else if ( strcmp ( level_name[level], "taggedpoints" ) == 0 ) {

        if ( strcmp ( word, "{" ) == 0 ) {
        }
        else if ( strcmp ( word, "}" ) == 0 ) {
          level = nlbrack - nrbrack;
        }
        else if ( word[0] == '[' ) {
        }
        else if ( strcmp ( word, "tagged" ) == 0 ) {
        }
        else {
          bad_num = bad_num + 1;
          printf ( "TAGGEDPOINTS: Bad data %s\n", word );
          return ERROR;
        }

      }
/*
  TEXTURE
*/
      else if ( strcmp ( level_name[level], "texture" ) == 0 ) {

        if ( strcmp ( word, "{" ) == 0 ) {
          texture_num = texture_num + 1;
        }
        else if ( strcmp ( word, "}" ) == 0 ) {
          level = nlbrack - nrbrack;
        }
        else if ( word[0] == '[' ) {
        }
        else if ( strcmp ( word, "ambient" ) == 0 ) {
        }
        else if ( strcmp ( word, "anim" ) == 0 ) {
        }
        else if ( strcmp ( word, "blending" ) == 0 ) {
        }
        else if ( strcmp ( word, "diffuse" ) == 0 ) {
        }
        else if ( strcmp ( word, "effect" ) == 0 ) {
        }
        else if ( strcmp ( word, "glbname" ) == 0 ) {
        }
        else if ( strcmp ( word, "method" ) == 0 ) {
        }
        else if ( strcmp ( word, "name" ) == 0 ) {
          count = sscanf ( next, "%s%n", word, &width );
          next = next + width;
          strcpy ( texture_name[texture_num-1], word );
        }
        else if ( strcmp ( word, "offset" ) == 0 ) {
        }
        else if ( strcmp ( word, "pixelinterp" ) == 0 ) {
        }
        else if ( strcmp ( word, "reflect" ) == 0 ) {
        }
        else if ( strcmp ( word, "reflmap" ) == 0 ) {
        }
        else if ( strcmp ( word, "repeat" ) == 0 ) {
        }
        else if ( strcmp ( word, "rotation" ) == 0 ) {
        }
        else if ( strcmp ( word, "roughness" ) == 0 ) {
        }
        else if ( strcmp ( word, "scaling" ) == 0 ) {
        }
        else if ( strcmp ( word, "specular" ) == 0 ) {
        }
        else if ( strcmp ( word, "transp" ) == 0 ) {
        }
        else if ( strcmp ( word, "txtsup_rot" ) == 0 ) {
        }
        else if ( strcmp ( word, "txtsup_scal" ) == 0 ) {
        }
        else if ( strcmp ( word, "txtsup_trans" ) == 0 ) {
        }
        else {
          bad_num = bad_num + 1;
          printf ( "TEXTURE: Bad data %s\n", word );
          return ERROR;
        }
      }
/*
  VERTICES
*/
      else if ( strcmp ( level_name[level], "vertices" ) == 0 ) {

        if ( strcmp ( word, "{" ) == 0 ) {
        }
        else if ( strcmp ( word, "}" ) == 0 ) {
          level = nlbrack - nrbrack;
        }
        else if ( word[0] == '[' ) {
        }
        else if ( strcmp ( word, "position" ) == 0 ) {

          count = sscanf ( next, "%f%n", &x, &width );
          next = next + width;

          count = sscanf ( next, "%f%n", &y, &width );
          next = next + width;

          count = sscanf ( next, "%f%n", &z, &width );
          next = next + width;

          if ( cor3_num < COR3_MAX ) {
            cor3[0][cor3_num] = x;
            cor3[1][cor3_num] = y;
            cor3[2][cor3_num] = z;
          }
          cor3_num = cor3_num + 1;
        }
        else {
          bad_num = bad_num + 1;
          printf ( "VERTICES: Bad data %s\n", word );
          return ERROR;
        }
      }
/*
  Any other word:
*/
      else {

      }
    }
  }

/*
  End of information in file.

  Check the "materials" defining a line.

  If COORDINDEX is -1, so should be the MATERIALINDEX.
  If COORDINDEX is not -1, then the MATERIALINDEX shouldn"t be either.
*/
  for ( i = 0; i < line_num; i++ ) {

    if ( line_dex[i] == -1 ) {
      line_material[i] = -1;
    }
    else if ( line_material[i] == -1 ) {
      line_material[i] = 0;
    }

  }
  return SUCCESS;
}
/******************************************************************************/

int hrc_write ( FILE* fileout )

/******************************************************************************/

/*
  Purpose:

    HRC_WRITE writes graphics data to an HRC SoftImage file.

  Examples:

    HRCH: Softimage 4D Creative Environment v3.00


    model
    {
      name         "cube_10x10"
      scaling      1.000 1.000 1.000
      rotation     0.000 0.000 0.000
      translation  0.000 0.000 0.000

      mesh
      {
        flag    ( PROCESS )
        discontinuity  60.000

        vertices   8
        {
          [0] position  -5.000  -5.000  -5.000
          [1] position  -5.000  -5.000  5.000
          [2] position  -5.000  5.000  -5.000
          [3] position  -5.000  5.000  5.000
          [4] position  5.000  -5.000  -5.000
          [5] position  5.000  -5.000  5.000
          [6] position  5.000  5.000  -5.000
          [7] position  5.000  5.000  5.000
        }

        polygons   6
        {
          [0] nodes  4
              {
                [0] vertex  0
                    normal  -1.000  0.000  0.000
                    uvTexture  0.000  0.000
                    vertexColor 255 178 178 178
                [1] vertex  1
                    normal  -1.000  0.000  0.000
                    uvTexture  0.000  0.000
                    vertexColor 255 178 178 178
                [2] vertex  3
                    normal  -1.000  0.000  0.000
                    uvTexture  0.000  0.000
                    vertexColor 255 178 178 178
                [3] vertex  2
                    normal  -1.000  0.000  0.000
                    uvTexture  0.000  0.000
                    vertexColor 255 178 178 178
              }
              material  0
          [1] nodes  4
             {
                [0] vertex  1
                    normal  0.000  0.000  1.000
                    uvTexture  0.000  0.000
                    vertexColor 255 178 178 178
                [1] vertex  5

    ...etc.....

          [5] nodes  4
              {
                [0] vertex  2
                    normal  0.000  1.000  0.000
                    uvTexture  0.000  0.000
                    vertexColor 255 178 178 178
                [1] vertex  3
                    normal  0.000  1.000  0.000
                    uvTexture  0.000  0.000
                    vertexColor 255 178 178 178
                [2] vertex  7
                    normal  0.000  1.000  0.000
                    uvTexture  0.000  0.000
                    vertexColor 255 178 178 178
                [3] vertex  6
                    normal  0.000  1.000  0.000
                    uvTexture  0.000  0.000
                    vertexColor 255 178 178 178
              }
              material  0
        }

        edges   12
        {
          [1] vertices  3  2
          [2] vertices  2  0
          [3] vertices  0  1
          [4] vertices  1  3
          [5] vertices  7  3
          [6] vertices  1  5
          [7] vertices  5  7
          [8] vertices  6  7
          [9] vertices  5  4
          [10] vertices  4  6
          [11] vertices  2  6
          [12] vertices  4  0
        }
      }

      material [0]
      {
      name           "kazoo"
      type           PHONG
      ambient        0.0  1.0  0.0
      diffuse        1.0  0.0  0.0
      specular       0.0  0.0  1.0
      exponent      50.0
      reflectivity   0.0
      transparency   0.0
      refracIndex    1.0
      glow           0
      coc            0.0
      }

      texture [0]
      {
      name          "/usr/users/foss/HOUSE/PICTURES/mellon"
      glbname       "t2d1"
      anim          STATIC
      method        XY
      repeat        1  1
      scaling       1.000  1.000
      offset        0.000  0.000
      pixelInterp
      effect        INTENSITY
      blending      1.000
      ambient       0.977
      diffuse       1.000
      specular      0.966
      reflect       0.000
      transp        0.000
      roughness     0.000
      reflMap       1.000
      rotation      0.000
      txtsup_rot    0.000  0.000  0.000
      txtsup_trans  0.000  0.000  0.000
      txtsup_scal   1.000  1.000  1.000
      }
    }

  Modified:

    25 June 1998

  Author:

    John Burkardt

*/
{
  int iface;
  int ivert;
  int j;
  int jhi;
  int jlo;
  int jrel;
  int k;
  int npts;
  int nseg;
  int text_num;

  nseg = 0;
  text_num = 0;

  fprintf ( fileout, "HRCH: Softimage 4D Creative Environment v3.00\n" );
  fprintf ( fileout, "\n" );
  fprintf ( fileout, "\n" );
  text_num = text_num + 3;

  fprintf ( fileout, "model\n" );
  fprintf ( fileout, "{\n" );
  fprintf ( fileout, "  name         \"%s\"\n", object_name );
  fprintf ( fileout, "  scaling      1.000 1.000 1.000\n" );
  fprintf ( fileout, "  rotation     0.000 0.000 0.000\n" );
  fprintf ( fileout, "  translation  0.000 0.000 0.000\n" );
  text_num = text_num + 6;

  if ( face_num > 0 ) {

    fprintf ( fileout, "\n" );
    fprintf ( fileout, "  mesh\n" );
    fprintf ( fileout, "  {\n" );
    fprintf ( fileout, "    flag    ( PROCESS )\n" );
    fprintf ( fileout, "    discontinuity  60.000\n" );
    text_num = text_num + 5;
/*
  Point coordinates.
*/
    if ( cor3_num > 0 ) {

      fprintf ( fileout, "\n" );
      fprintf ( fileout, "    vertices %d\n", cor3_num );
      fprintf ( fileout, "    {\n" );
      text_num = text_num + 3;

      for ( j = 0; j < cor3_num; j++ ) {

        fprintf ( fileout, "      [%d] position %f %f %f\n", j, cor3[0][j], 
          cor3[1][j], cor3[2][j] );
        text_num = text_num + 1;
      }
      fprintf ( fileout, "    }\n" );
      text_num = text_num + 1;
    }
/*
  Faces.
*/
    fprintf ( fileout, "\n" );
    fprintf ( fileout, "    polygons %d\n", face_num );
    fprintf ( fileout, "    {\n" );
    text_num = text_num + 3;

    for ( iface = 0; iface < face_num; iface++ ) {

      fprintf ( fileout, "      [%d] nodes %d\n", iface, face_order[iface] );
      fprintf ( fileout, "      {\n" );
      text_num = text_num + 2;

      for ( ivert = 0; ivert < face_order[iface]; ivert++ ) {

        fprintf ( fileout, "        [%d] vertex %d\n", ivert, face[ivert][iface] );
        fprintf ( fileout, "            normal %f %f %f\n", 
          vertex_normal[0][ivert][iface], 
          vertex_normal[1][ivert][iface], vertex_normal[2][ivert][iface] );
        fprintf ( fileout, "            uvTexture  %f %f\n", 
          vertex_tex_uv[0][ivert][iface], vertex_tex_uv[1][ivert][iface] );
        fprintf ( fileout, "            vertexColor  255 178 178 178\n" );
        text_num = text_num + 4;
      }
      fprintf ( fileout, "      }\n" );
      fprintf ( fileout, "      material %d\n", face_material[iface] );
      text_num = text_num + 2;
    }
    fprintf ( fileout, "    }\n" );
    fprintf ( fileout, "  }\n" );
    text_num = text_num + 2;
  }
/*
  IndexedLineSet.
*/
  if ( line_num > 0 ) {

    nseg = 0;

    jhi = -1;

    for ( ;; ) {

      jlo = jhi + 1;
/*
  Look for the next index JLO that is not -1.
*/
      while ( jlo < line_num ) {
        if ( line_dex[jlo] != -1 ) {
          break;
        }
        jlo = jlo + 1;
      }

      if ( jlo >= line_num ) {
        break;
      }
/*
  Look for the highest following index JHI that is not -1.
*/
      jhi = jlo + 1;

      while ( jhi < line_num ) {
        if ( line_dex[jhi] == -1 ) {
          break;
        }
        jhi = jhi + 1;
      }

      jhi = jhi - 1;
/*
  Our next line segment involves LINE_DEX indices JLO through JHI.
*/     
      nseg = nseg + 1;
      npts = jhi + 1 - jlo;

      fprintf ( fileout, "\n" );
      fprintf ( fileout, "  spline\n" );
      fprintf ( fileout, "  {\n" );
      fprintf ( fileout, "    name     \"spl%d\"\n", nseg );
      fprintf ( fileout, "    type     LINEAR\n" );
      fprintf ( fileout, "    nbKeys   %d\n", npts );
      fprintf ( fileout, "    tension  0.000\n" );
      fprintf ( fileout, "    step     1\n" );
      fprintf ( fileout, "\n" );
      text_num = text_num + 9;

      fprintf ( fileout, "    controlpoints\n" );
      fprintf ( fileout, "    {\n" );
      text_num = text_num + 2;

      for ( j = jlo; j <= jhi; j++ ) {
        jrel = j - jlo;
        k = line_dex[j];
        fprintf ( fileout, "      [%d] position %f %f %f\n", jrel,
          cor3[0][k], cor3[1][k], cor3[2][k] );
        text_num = text_num + 1;
      }

      fprintf ( fileout, "    }\n" );
      fprintf ( fileout, "  }\n" );
      text_num = text_num + 2;
    }
  }
/*
  MATERIALS
*/
  for ( i = 0; i < material_num; i++ ) {

    fprintf ( fileout, "  material [%d]\n", i );
    fprintf ( fileout, "  {\n" );
    fprintf ( fileout, "    name           \"%s\"\n", material_name[i] );
    fprintf ( fileout, "    type           PHONG\n" );
    fprintf ( fileout, "    ambient        %f %f %f\n", material_rgba[0][i],
      material_rgba[1][i], material_rgba[2][i] );
    fprintf ( fileout, "    diffuse        %f %f %f\n", material_rgba[0][i],
      material_rgba[1][i], material_rgba[2][i] );
    fprintf ( fileout, "    specular       %f %f %f\n", material_rgba[0][i],
      material_rgba[1][i], material_rgba[2][i] );
    fprintf ( fileout, "    exponent      50.0\n" );
    fprintf ( fileout, "    reflectivity   0.0\n" );
    fprintf ( fileout, "    transparency   %f\n", 1.0 - material_rgba[3][i] );
    fprintf ( fileout, "    refracIndex    1.0\n" );
    fprintf ( fileout, "    glow           0\n" );
    fprintf ( fileout, "    coc            0.0\n" );
    fprintf ( fileout, "  }\n" );

    text_num = text_num + 14;

  }
/*
  TEXTURES
*/
  for ( i = 0; i < texture_num; i++ ) {

    fprintf ( fileout, "  texture [%d]\n", i );
    fprintf ( fileout, "  {\n" );
    fprintf ( fileout, "    name           \"%s\"\n", texture_name[i] );
    fprintf ( fileout, "    glbname        \"t2d1\"\n" );
    fprintf ( fileout, "    anim           STATIC\n" );
    fprintf ( fileout, "    method         XY\n" );
    fprintf ( fileout, "    repeat         1 1\n" );
    fprintf ( fileout, "    scaling        1.000  1.000\n" );
    fprintf ( fileout, "    offset         0.000  0.000\n" );
    fprintf ( fileout, "    pixelInterp\n" );
    fprintf ( fileout, "    effect         INTENSITY\n" );
    fprintf ( fileout, "    blending       1.000\n" );
    fprintf ( fileout, "    ambient        0.977\n" );
    fprintf ( fileout, "    diffuse        1.000\n" );
    fprintf ( fileout, "    specular       0.966\n" );
    fprintf ( fileout, "    reflect        0.000\n" );
    fprintf ( fileout, "    transp         0.000\n" );
    fprintf ( fileout, "    roughness      0.000\n" );
    fprintf ( fileout, "    reflMap        1.000\n" );
    fprintf ( fileout, "    rotation       0.000\n" );
    fprintf ( fileout, "    txtsup_rot     0.000  0.000  0.000\n" );
    fprintf ( fileout, "    txtsup_trans   0.000  0.000  0.000\n" );
    fprintf ( fileout, "    txtsup_scal    1.000  1.000  1.000\n" );
    fprintf ( fileout, "  }\n" );

    text_num = text_num + 25;

  }
  fprintf ( fileout, "}\n" );
  text_num = text_num + 1;
/*
  Report.
*/
  printf ( "\n" );
  printf ( "HRC_WRITE - Wrote %d text lines.\n", text_num );

  return SUCCESS;
}
/******************************************************************************/

void init_program_data ( void )

/******************************************************************************/

/*
  Purpose:

    INIT_PROGRAM_DATA initializes the internal program data.

  Modified:

    26 May 1999

  Author:

    John Burkardt
*/
{
  byte_swap = FALSE;
  debug = 0;
  line_prune = 1;
  color_num = 0;
  cor3_num = 0;
  face_num = 0;
  line_num = 0;

  if ( debug ) {
    printf ( "\n" );
    printf ( "INIT_PROGRAM_DATA: Program data initialized.\n" );
  }

  return;

}
/******************************************************************************/

int interact ( void )

/******************************************************************************/

/*
  Purpose:
   
    INTERACT carries on an interactive session with the user.

  Modified:

    22 May 1999

  Author:
 
    John Burkardt
*/
{
  int    i;
  int    icor3;
  int    ierror;
  int    iface;
  int    itemp;
  int    ivert;
  int    j;
  int    jvert;
  int    m;
  char  *next;
  float  temp;
  float  x;
  float  y;
  float  z;

  strcpy ( filein_name, "NO_IN_NAME" );
  strcpy ( fileout_name, "NO_OUT_NAME" );

/*  
  Say hello. 
*/
  hello ( );
/*  
  Get the next user command. 
*/
  printf ( "\n" );
  printf ( "Enter command (H for help)\n" );

  while ( fgets ( input, LINE_MAX_LEN, stdin ) != NULL ) {
/*  
  Advance to the first nonspace character in INPUT. 
*/
    for ( next = input; *next != '\0' && isspace(*next); next++ ) {
    }
/*  
  Skip blank lines and comments. 
*/
    if ( *next == '\0' ) {
      continue;
    }
/*  
  Command: << FILENAME 
  Append new data to current graphics information.
*/
    if ( *next == '<' && *(next+1) == '<' ) {

      next = next + 2;
      sscanf ( next, "%s", filein_name );

      ierror = data_read ( );

      if ( ierror == ERROR ) {
        printf ( "\n" );
        printf ( "INTERACT - Fatal error!\n" );
        printf ( "  DATA_READ failed to read input data.\n" );
      }
    }
/*  
  Command: < FILENAME 
*/
    else if ( *next == '<' ) {

      next = next + 1;
      sscanf ( next, "%s", filein_name );

      data_init ( );

      ierror = data_read ( );

      if ( ierror == ERROR ) {
        printf ( "\n" );
        printf ( "INTERACT - Fatal error!\n" );
        printf ( "  DATA_READ failed to read input data.\n" );
      }
    }
/*  
  Command: > FILENAME 
*/
    else if ( *next == '>' ) {

      next = next + 1;
      sscanf ( next, "%s", fileout_name ); 

      ierror = data_write ( );
 
      if ( ierror == ERROR ) {
        printf ( "\n" );
        printf ( "INTERACT - Fatal error!\n" );
        printf ( "  OUTPUT_DATA failed to write output data.\n" );
      }

    }
/*
  B: Switch byte swapping option.
*/
    else if ( *next == 'B' || *next == 'b' ) {

      if ( byte_swap == TRUE ) {
        byte_swap = FALSE;
        printf ( "Byte_swapping reset to FALSE.\n" );
      }
      else {
        byte_swap = TRUE;
        printf ( "Byte_swapping reset to TRUE.\n" );
      }

    }
/*
  D: Switch debug option.
*/
    else if ( *next == 'D' || *next == 'd' ) {
      if ( debug ) {
        debug = 0;
        printf ( "Debug reset to FALSE.\n" );
      }
      else {
        debug = 1;
        printf ( "Debug reset to TRUE.\n" );
      }
    }
/*  
  F: Check a face. 
*/
    else if ( *next == 'f' || *next == 'F' ) {
      printf ( "\n" );
      printf ( "  Enter a face index between 0 and %d:", face_num-1 );
      scanf ( "%d", &iface );
      face_print ( iface );
    }
/*  
  H: Help
*/
    else if ( *next == 'h' || *next == 'H' ) {
      help ( );
    }
/*
  I: Print change information. 
*/
    else if ( *next == 'i' || *next == 'I') {
      news ( );
    }
/*
  LINES: 
  Convert face information to lines.
*/
    else if ( *next == 'l' || *next == 'L') {

      if ( face_num > 0 ) {

        printf ( "\n" );
        printf ( "INTERACT - Note:\n" );
        printf ( "  Face information will be converted\n" );
        printf ( "  to line information.\n" );

          face_to_line ( );

          if ( line_num > LINES_MAX ) {

            printf ( "\n" );
            printf ( "INTERACT - Note:\n" );
            printf ( "  Some face information was lost.\n" );
            printf ( "  The maximum number of lines is %d,\n", LINES_MAX );
            printf ( "  but we would need at least %d.\n", line_num );

            line_num = LINES_MAX;

          }

          face_num = 0;
      }
      else {

        printf ( "\n" );
        printf ( "INTERACT - Note:\n" );
        printf ( "  There were no faces to convert.\n" );

      }

    }
/*
  N: Recompute normal vectors.
*/
    else if ( *next == 'n' || *next == 'N') {

      for ( iface = 0; iface < face_num; iface++ ) {
        for ( i = 0; i < 3; i++ ) {
          face_normal[i][iface] = 0.0;
        }
      }

      for ( iface = 0; iface < face_num; iface++ ) {
         for ( ivert = 0; ivert < face_order[iface]; ivert++ ) {
          for ( i = 0; i < 3; i++ ) {
            vertex_normal[i][ivert][iface] = 0.0;
          }
        }
      }

      vertex_normal_set ( );

      cor3_normal_set ( );

      face_normal_ave ( );
    }
/*
  P: Line pruning optiont
*/
    else if ( *next == 'p' || *next == 'P' ) {

      printf ( "\n" );
      printf ( "INTERACT - SET LINE PRUNING OPTION.\n" );
      printf ( "\n" );
      printf ( "  LINE_PRUNE = 0 means no line pruning.\n" );
      printf ( "               nonzero means line pruning.\n" );
      printf ( "\n" );
      printf ( "  Current value is LINE_PRUNE = %d.\n", line_prune );
      printf ( "\n" );
      printf ( "  Enter new value for LINE_PRUNE.\n" );

      if ( fgets ( input, LINE_MAX_LEN, stdin ) == NULL ) {
        printf ( "  ??? Error trying to read input.\n" );
      }
      else {
        sscanf ( input, "%d", &line_prune );
        printf ( "  New value is LINE_PRUNE = %d.\n", line_prune );
      }
    }
/*
  Q: Quit
*/
    else if ( *next == 'q' || *next == 'Q' ) {
      printf ( "\n" );
      printf ( "INTERACT - Normal end of execution.\n" );
      return SUCCESS;
    }
/*
  R: Reverse normal vectors. 
*/
    else if ( *next == 'r' || *next == 'R' ) {

      for ( icor3 = 0; icor3 < cor3_num; icor3++ ) {
        for ( i = 0; i < 3; i++ ) {
          cor3_normal[i][icor3] = - cor3_normal[i][icor3];
        }
      }

      for ( iface = 0; iface < face_num; iface++ ) {
        for ( i = 0; i < 3; i++ ) {
          face_normal[i][iface] = - face_normal[i][iface];
        }
      }

      for ( iface = 0; iface < face_num; iface++ ) {
        for ( ivert = 0; ivert < face_order[iface]; ivert++ ) {
          for ( i = 0; i < 3; i++ ) {
            vertex_normal[i][ivert][iface] = 
              - vertex_normal[i][ivert][iface];
          }
        }
      }
      printf ( "\n" );
      printf ( "INTERACT - Note:\n" );
      printf ( "  Reversed node, face and vertex normals.\n" );
    }
/*  
  S: Select a few faces, discard the rest.
*/
    else if ( *next == 's' || *next == 'S' ) {
      face_subset ( );
    }
/*  
  T: Transform the data.
*/
    else if ( *next == 't' || *next == 'T' ) {

      printf ( "\n" );
      printf ( "For now, we only offer point scaling.\n" );
      printf ( "Enter X, Y, Z scale factors:\n" );

      scanf ( "%f %f %f", &x, &y, &z );

      for ( j = 0; j < cor3_num; j++ ) {
        cor3[0][j] = x * cor3[0][j];
        cor3[1][j] = y * cor3[1][j];
        cor3[2][j] = z * cor3[2][j];
      }

      for ( iface = 0; iface < face_num; iface++ ) {
        for ( i = 0; i < 3; i++ ) {
          face_normal[i][iface] = 0.0;
        }
      }

      for ( iface = 0; iface < face_num; iface++ ) {
         for ( ivert = 0; ivert < face_order[iface]; ivert++ ) {
          for ( i = 0; i < 3; i++ ) {
            vertex_normal[i][ivert][iface] = 0.0;
          }
        }
      }

      vertex_normal_set ( );

      cor3_normal_set ( );

      face_normal_ave ( );
    }
/*
  U: Renumber faces, count objects:
*/
    else if ( *next == 'u' || *next == 'U' ) {
    }
/*
  V: Convert polygons to triangles:
*/
    else if ( *next == 'v' || *next == 'V' ) {
    }
/*
  W: Reverse the face node ordering. 
*/
    else if ( *next == 'w' || *next == 'W' ) {

      if ( face_num > 0 ) {

        for ( iface = 0; iface < face_num; iface++ ) {

          m = face_order[iface];

          for ( ivert = 0; ivert < m/2; ivert++ ) {

            jvert = m - ivert - 1;

            itemp = face[ivert][iface];
            face[ivert][iface] = face[jvert][iface];
            face[jvert][iface] = itemp;

            itemp = vertex_material[ivert][iface];
            vertex_material[ivert][iface] = vertex_material[jvert][iface];
            vertex_material[jvert][iface] = itemp;

            for ( i = 0; i < 3; i++ ) {
              temp = vertex_normal[i][ivert][iface];
              vertex_normal[i][ivert][iface] = 
                vertex_normal[i][jvert][iface];
              vertex_normal[i][jvert][iface] = temp;
            }
          }
        }
        printf ( "\n" );
        printf ( "INTERACT - Note:\n" );
        printf ( "  Reversed face node ordering.\n" );
      }
    }
/*
  Command: ???  
*/
    else {
      printf ( "\n" );
      printf ( "INTERACT: Warning!\n" );
      printf ( "  Your command was not recognized.\n" );
    }

    printf ( "\n" );
    printf ( "Enter command (H for help)\n" );

  }
  return SUCCESS;
}
/******************************************************************************/

int iv_read ( FILE *filein )

/******************************************************************************/

/*
  Purpose:

    IV_READ reads graphics information from an Inventor file.

  Example:

     #Inventor V2.0 ascii

     Separator {
       Info {
         string "Inventor file generated by IVCON.
         Original data in file cube.iv."
       }
       Separator {
         LightModel {
           model PHONG
         }
         MatrixTransform { matrix
           0.9  0.0  0.0  0.0
           0.0 -0.9  0.0  0.0
           0.0  0.0 -1.5  0.0
           0.0  0.0  0.0  1.0
         }
         Material {
           ambientColor  0.2 0.2 0.2
           diffuseColor  [
             0.8 0.8 0.8,
             0.7 0.1 0.1,
             0.1 0.8 0.2,
           ]
           emissiveColor 0.0 0.0 0.0
           specularColor 0.0 0.0 0.0
           shininess     0.2
           transparency  [
             0.0, 0.5, 1.0,
           ]
         }
         Texture2 {
           filename      "fred.rgb"
           wrapS         REPEAT
           wrapT         REPEAT
           model         MODULATE
           blendColor    0.0 0.0 0.0
         }

         MaterialBinding {
           value PER_VERTEX_INDEXED
         }
         NormalBinding {
           value PER_VERTEX_INDEXED
         }
         TextureCoordinateBinding {
           value PER_VERTEX_INDEXED
         }

         ShapeHints {
           vertexOrdering COUNTERCLOCKWISE
           shapeType UNKNOWN_SHAPE_TYPE
           faceType CONVEX
           creaseAngle 6.28319
         }

         Coordinate3 {
           point [
                8.59816       5.55317      -3.05561,
                8.59816       2.49756      0.000000E+00,
                ...etc...
                2.48695       2.49756      -3.05561,
           ]
         }

         Normal {
           vector [
             0.71 0.71 0.0,
             ...etc...
             0.32 0.32 0.41,
           ]
         }

         TextureCoordinate2 {
           point [
                0.0  1.0,
                0.1, 0.8,
                ...etc...
                0.4  0.7,
           ]
         }

         IndexedLineSet {
           coordIndex [
              0,    1,    2,   -1,
              3,    4,    5,   -1,
              7,    8,    9,   -1,
            ...etc...
            189,  190,  191,   -1,
           ]
           materialIndex [
              0,    0,    0,   -1,
              1,    1,    1,   -1,
              2,    2,    2,   -1,
            ...etc...
             64,   64,   64,   -1,
           ]
         }

         IndexedFaceSet {
           coordIndex [
              0,    1,    2,   -1,
              3,    4,    5,   -1,
              7,    8,    9,   -1,
            ...etc...
            189,  190,  191,   -1,
           ]
           materialIndex [
              0,    0,    0,   -1,
              1,    1,    1,   -1,
              2,    2,    2,   -1,
            ...etc...
             64,   64,   64,   -1,
           ]
           normalIndex [
              0,    0,    0,   -1,
              1,    1,    1,   -1,
              2,    2,    2,   -1,
            ...etc...
             64,   64,   64,   -1,
           ]
           textureCoordIndex [
              0,    0,    0,   -1,
              1,    1,    1,   -1,
              2,    2,    2,   -1,
            ...etc...
             64,   64,   64,   -1,
           ]
         }

         IndexedTriangleStripSet {
           vertexProperty VertexProperty {
             vertex [ x y z,
                      ...
                      x y z ]
             normal [ x y z,
                      ...
                      x y z ]
             materialBinding OVERALL
             normalBinding PER_VERTEX_INDEXED
           }
           coordIndex [ 
             i, j, k, l, m, -1, 
             n, o, p, q, r, s, t, u, -1,
             v, w, x, -1 
                 ..., -1 ]
           normalIndex -1
         }

       }
     }

  Modified:

    01 July 1999

  Author:

    John Burkardt
*/
{
  char  c;
  int   count;
  int   i;
  int   icol;
  int   icolor;
  int   icface;
  int   inormface;
  int   iface_num;
  int   irow;
  int   iuv;
  int   ivert;
  int   iword;
  int   ix;
  int   ixyz;
  int   iy;
  int   iz;
  int   j;
  int   jval;
  int   level;
  char *next;
  int   nlbrack;
  int   nrbrack;
  int   nu;
  int   null_index;
  int   cor3_num_old;
  int   line_num2;
  int   face_num2;
  int   normal_num_temp;
  int   text_numure_temp;
  int   nv;
  int   result;
  float rval;
  int   width;
  char  word[LINE_MAX_LEN];
  char  word1[LINE_MAX_LEN];
  char  wordm1[LINE_MAX_LEN];
  float xvec[3];

  icface = 0;
  icol = -1;
  inormface = 0;
  iface_num = face_num;
  irow = 0;
  ix = 0;
  ixyz = 0;
  iy = 0;
  iz = 0;
  jval = 0;
  level = 0;
  strcpy ( level_name[0], "Top" );
  nlbrack = 0;
  nrbrack = 0;
  nu = 0;
  cor3_num_old = cor3_num;
  face_num2 = face_num;
  line_num2 = line_num;
  normal_num_temp = 0;
  text_numure_temp = 0;
  nv = 0;
  rval = 0.0;
  strcpy ( word, " " );
  strcpy ( wordm1, " " );
/*
  Read the next line of text from the input file.
*/
  for ( ;; ) {

    if ( fgets ( input, LINE_MAX_LEN, filein ) == NULL ) {
      break;
    }

    text_num = text_num + 1;
    next = input;
    iword = 0;
/*
  Remove all commas from the line, so we can use SSCANF to read
  numeric items.
*/
    i = 0;
    while ( input[i] != '\0' ) {
      if ( input[i] == ',' ) {
        input[i] = ' ';
      }
      i++;
    }
/*
  Force brackets and braces to be buffered by spaces.
*/
    i = 0;
    while ( input[i] != '\0' ) {
      i++;
    }
    null_index = i;

    i = 0;
    while ( input[i] != '\0' && i < LINE_MAX_LEN ) {

      if ( input[i] == '[' || input[i] == ']' || 
           input[i] == '{' || input[i] == '}' ) {

        result = char_pad ( &i, &null_index, input, LINE_MAX_LEN );
        if ( result == ERROR ) {
          break;
        }
      } 
      else {
        i++;
      }
    }
/*
  Read a word from the line.
*/
    for ( ;; ) {

      strcpy ( wordm1, word );
      strcpy ( word, " " );

      count = sscanf ( next, "%s%n", word, &width );
      next = next + width;

      if ( count <= 0 ) {
        break;
      }

      iword = iword + 1;

      if ( iword == 1 ) {
        strcpy ( word1, word );
      }
/*
  The first line of the file must be the header.
*/
      if ( text_num == 1 ) {

        if ( leqi ( word1, "#Inventor" ) != TRUE ) { 
          printf ( "\n" );
          printf ( "IV_READ - Fatal error!\n" );
          printf ( "  The input file has a bad header.\n" );
          return ERROR;
        }
        else {
          comment_num = comment_num + 1;
        }
        break;
      }
/*
  A comment begins anywhere with '#'.
  Skip the rest of the line.
*/
      if ( word[1] == '#' ) {
        comment_num = comment_num + 1;
        break;
      }
/*
  If the word is a curly or square bracket, count it.
  If the word is a left bracket, the previous word is the name of a node.
*/
      if ( strcmp ( word, "{" ) == 0 || strcmp ( word, "[" ) == 0 ) {
        nlbrack = nlbrack + 1;
        level = nlbrack - nrbrack;
        strcpy ( level_name[level], wordm1 );
        if ( debug ) {
          printf ( "Begin level: %s\n", wordm1 );
        }
      }
      else if ( strcmp ( word, "}" ) == 0 || strcmp ( word, "]" ) == 0 ) {
        nrbrack = nrbrack + 1;

        if ( nlbrack < nrbrack ) {
          printf ( "\n" );
          printf ( "IV_READ - Fatal error!\n" );
          printf ( "  Extraneous right bracket on line %d.\n", text_num );
          printf ( "  Currently processing field %s\n.", level_name[level] );
          return ERROR;
        }
      }
/*
  BASECOLOR
*/
      if ( leqi ( level_name[level], "BASECOLOR" ) == TRUE ) {

        if ( strcmp ( word, "{" ) == 0 ) {
        }
        else if ( strcmp ( word, "}" ) == 0 ) {
          level = nlbrack - nrbrack;
        }
        else if ( leqi ( word, "RGB" ) == TRUE ) {
        }
        else {
          bad_num = bad_num + 1;
          printf ( "Bad data %s\n", word );
        }
      }
/*
  COORDINATE3
*/
      else if ( leqi ( level_name[level], "COORDINATE3" ) == TRUE ) {

        if ( strcmp ( word, "{" ) == 0 ) {
        }
        else if ( strcmp ( word, "}" ) == 0 ) {
          level = nlbrack - nrbrack;
        }
        else if ( leqi ( word, "POINT" ) == TRUE ) {
        }
        else {
          bad_num = bad_num + 1;
          printf ( "COORDINATE3: Bad data %s\n", word );
        }
      }
/*
  COORDINATE4
*/
      else if ( leqi ( level_name[level], "COORDINATE4" ) == TRUE ) {

        if ( strcmp ( word, "{" ) == 0 ) {
        }
        else if ( strcmp ( word, "}" ) == 0 ) {
          level = nlbrack - nrbrack;
        }
        else if ( leqi ( word, "POINT" ) == TRUE ) {
        }
        else {
          bad_num = bad_num + 1;
          printf ( "COORDINATE4: Bad data %s\n", word );
        }
      }
/*
  COORDINDEX
*/
      else if ( leqi ( level_name[level], "COORDINDEX" ) == TRUE ) {

        if ( strcmp ( word, "[" ) == 0 ) {
          ivert = 0;
        }
        else if ( strcmp ( word, "]" ) == 0 ) {
          level = nlbrack - nrbrack;
        }
/*
  (indexedlineset) COORDINDEX
*/
        else if ( leqi ( level_name[level-1], "INDEXEDLINESET" ) == TRUE ) {

          count = sscanf ( word, "%d%n", &jval, &width );

          if ( count > 0 ) {

            if ( jval < -1 ) {
              bad_num = bad_num + 1;
            }
            else {
              if ( line_num < LINES_MAX ) {
                if ( jval != -1 ) {
                  jval = jval + cor3_num_old;
                }
                line_dex[line_num] = jval;
              }
              line_num = line_num + 1;
            }
          }
          else {
            bad_num = bad_num + 1;
          }
        }
/*
  (indexedfaceset) COORDINDEX
  Warning: If the list of indices is not terminated with a final -1, then
  the last face won't get counted.
*/
        else if ( leqi ( level_name[level-1], "INDEXEDFACESET" ) == TRUE ) {

          count = sscanf ( word, "%d%n", &jval, &width );

          if ( count > 0 ) {
            if ( jval == -1 ) {
              ivert = 0;
              face_num = face_num + 1;
            }
            else {
              if ( ivert == 0 ) {
                if ( face_num < FACE_MAX ) {
                  face_order[face_num] = 0;
                }
              }
              if ( face_num < FACE_MAX ) {
                face_order[face_num] = face_order[face_num] + 1;
                face[ivert][face_num] = jval + cor3_num_old;
                ivert = ivert + 1;
              }
            }
          }
        }
/*
  (indexednurbssurface) COORDINDEX
*/
        else if ( leqi ( level_name[level-1], "INDEXEDNURBSSURFACE" ) == TRUE ) {
        }
/*
  (indexedtrianglestripset) COORDINDEX

  First three coordinate indices I1, I2, I3 define a triangle.
  Next triangle is defined by I2, I3, I4 (actually, I4, I3, I2
  to stay with same counterclockwise sense).
  Next triangle is defined by I3, I4, I5 ( do not need to reverse
  odd numbered triangles) and so on.
  List is terminated with -1.
*/
        else if ( leqi ( level_name[level-1], "INDEXEDTRIANGLESTRIPSET" ) == TRUE ) {

          count = sscanf ( word, "%d%n", &jval, &width );

          if ( count > 0 ) {

            if ( jval == -1 ) {
              ivert = 0;
            }
            else {

              ix = iy;
              iy = iz;
              iz = jval + cor3_num_old;

              if ( ivert == 0 ) {
                if ( face_num < FACE_MAX ) {
                  face[ivert][face_num] = jval + cor3_num_old;
                  face_order[face_num] = 3;
                }
              }
              else if ( ivert == 1 ) {
                if ( face_num < FACE_MAX ) {
                  face[ivert][face_num] = jval + cor3_num_old;
                }
              }
              else if ( ivert == 2 ) {
                if ( face_num < FACE_MAX ) {
                  face[ivert][face_num] = jval + cor3_num_old;
                }
                face_num = face_num + 1;
              }
              else {

                if ( face_num < FACE_MAX ) {
                  face_order[face_num] = 3;
                  if ( ( ivert % 2 ) == 0 ) {
                    face[0][face_num] = ix;
                    face[1][face_num] = iy;
                    face[2][face_num] = iz;
                  }
                  else {
                    face[0][face_num] = iz;
                    face[1][face_num] = iy;
                    face[2][face_num] = ix;
                  }
                }
                face_num = face_num + 1;
              }
              ivert = ivert + 1;
/*
  Very very tentative guess as to how indices into the normal
  vector array are set up...
*/
              if ( face_num < FACE_MAX && ivert > 2 ) {
                for ( i = 0; i < 3; i++ ) {
                  face_normal[i][face_num] = normal_temp[i][ix];
                }
              }
            }
          }
        }
      }
/*
  INDEXEDFACESET
*/
      else if ( leqi ( level_name[level], "INDEXEDFACESET" ) == TRUE ) {

        if ( strcmp ( word, "{" ) == 0 ) {
        }
        else if ( strcmp ( word, "}" ) == 0 ) {
          level = nlbrack - nrbrack;
        }
        else if ( leqi ( word, "COORDINDEX" ) == TRUE ) {
          ivert = 0;
        }
        else if ( leqi ( word, "MATERIALINDEX" ) == TRUE ) {
        }
        else if ( leqi ( word, "NORMALINDEX" ) == TRUE ) {
        }
        else if ( leqi ( word, "TEXTURECOORDINDEX" ) == TRUE ) {
          if ( texture_num <= 0 ) {
            texture_num = 1;
            strcpy ( texture_name[0], "Texture_0000" );
          }
        }
        else {
          bad_num = bad_num + 1;
          printf ( "Bad data %s\n", word );
        }
      }
/*
  INDEXEDLINESET
*/
      else if ( leqi ( level_name[level], "INDEXEDLINESET" ) == TRUE ) {

        if ( strcmp ( word, "{" ) == 0 ) {
        }
        else if ( strcmp ( word, "}" ) == 0 ) {
          level = nlbrack - nrbrack;
        }
        else if ( leqi ( word, "COORDINDEX" ) == TRUE ) {
        }
        else if ( leqi ( word, "MATERIALINDEX" ) == TRUE ) {
        }
        else {
          bad_num = bad_num + 1;
          printf ( "Bad data %s\n", word );
        }
      }
/*
  INDEXEDNURBSSURFACE
*/
      else if ( leqi ( level_name[level], "INDEXEDNURBSSURFACE" ) == TRUE ) {

        if ( strcmp ( word, "{" ) == 0 ) {
        }
        else if ( strcmp ( word, "}" ) == 0 ) {
          level = nlbrack - nrbrack;
        }
        else if ( leqi ( word, "NUMUCONTROLPOINTS") == TRUE ) {

          count = sscanf ( word, "%d%n", &jval, &width );

          if ( count > 0 ) {
            nu = jval;
            if ( debug ) {
              printf ( "NU = %d\n", nu );
            }
          }
          else {
            nu = 0;
            bad_num = bad_num + 1;
            printf ( "Bad data %s\n", word );
          }
        }
        else if ( leqi ( word, "NUMVCONTROLPOINTS" ) == TRUE ) {

          count = sscanf ( word, "%d%n", &jval, &width );

          if ( count > 0 ) {
            nv = jval;
            if ( debug ) {
              printf ( "NV = %d\n", nv );
            }
          }
          else {
            nv = 0;
            bad_num = bad_num + 1;
          }
        }
        else if ( leqi ( word, "COORDINDEX" ) == TRUE ) {
        }
        else if ( leqi ( word, "UKNOTVECTOR" ) == TRUE ) {
        }
        else if ( leqi ( word, "VKNOTVECTOR" ) == TRUE ) {
        }
        else {
          bad_num = bad_num + 1;
          printf ( "Bad data %s\n", word );
        }
      }
/*
  INDEXEDTRIANGLESTRIPSET
*/
      else if ( leqi ( level_name[level], "INDEXEDTRIANGLESTRIPSET" ) == TRUE ) {

        if ( strcmp ( word, "{" ) == 0 ) {
        }
        else if ( strcmp ( word, "}" ) == 0 ) {
          level = nlbrack - nrbrack;
        }
        else if ( leqi ( word, "VERTEXPROPERTY" ) == TRUE ) {
          count = sscanf ( next, "%s%n", word, &width );
          next = next + width;
        }
        else if ( leqi ( word, "COORDINDEX" ) == TRUE ) {
          ivert = 0;
        }
        else if ( leqi ( word, "NORMALINDEX" ) == TRUE ) {
          count = sscanf ( next, "%s%n", word, &width );
          next = next + width;
        }
        else {
          bad_num = bad_num + 1;
          printf ( "Bad data %s\n", word );
        }
      }
/*
  INFO
*/
      else if ( leqi ( level_name[level], "INFO" ) == TRUE ) {

        if ( strcmp ( word, "{" ) == 0 ) {
        }
        else if ( strcmp ( word, "}" ) == 0 ) {
          level = nlbrack - nrbrack;
        }
        else if ( leqi ( word, "STRING" ) == TRUE ) {
        }
        else if ( strcmp ( word, "\"" ) == 0 ) {
        }
        else {
        }
      }
/*
  LIGHTMODEL
  Read, but ignore.
*/
      else if ( leqi ( level_name[level], "LIGHTMODEL" ) == TRUE ) {

        if ( strcmp ( word, "{" ) == 0 ) {
        }
        else if ( strcmp ( word, "}" ) == 0 ) {
          level = nlbrack - nrbrack;
        }
        else if ( leqi ( word, "model" ) == TRUE ) {
        }
        else {
        }
      }
/*
  MATERIAL
  Read, but ignore.
*/
      else if ( leqi ( level_name[level],"MATERIAL" ) == TRUE ) {

        if ( strcmp ( word, "{" ) == 0 ) {
        }
        else if ( strcmp ( word, "}" ) == 0 ) {
          level = nlbrack - nrbrack;
        }
        else if ( leqi ( word, "AMBIENTCOLOR" ) == TRUE ) {
        }
        else if ( leqi ( word, "EMISSIVECOLOR" ) == TRUE ) {
        }
        else if ( leqi ( word, "DIFFUSECOLOR" ) == TRUE ) {
        }
        else if ( leqi ( word, "SHININESS" ) == TRUE ) {
        }
        else if ( leqi ( word, "SPECULARCOLOR" ) == TRUE ) {
        }
        else if ( leqi ( word, "TRANSPARENCY" ) == TRUE ) {
        }
        else {
        }
      }
/*
  MATERIALBINDING
  Read, but ignore
*/
      else if ( leqi ( level_name[level], "MATERIALBINDING" ) == TRUE ) {

        if ( strcmp ( word, "{" ) == 0 ) {
        }
        else if ( strcmp ( word, "}" ) == 0 ) {
          level = nlbrack - nrbrack;
        }
        else if ( leqi ( word, "VALUE" ) == TRUE ) {
          count = sscanf ( next, "%s%n", material_binding, &width );
          next = next + width;
        }
        else {
          count = sscanf ( next, "%f%n", &rval, &width );
          next = next + width;

          if ( count > 0 ) {
          }
          else {
            bad_num = bad_num + 1;
            printf ( "Bad data %s\n", word );
          }
        }
      }
/*
  MATERIALINDEX
*/
      else if ( leqi ( level_name[level], "MATERIALINDEX" ) == TRUE ) {

        if ( strcmp ( word, "[" ) == 0 ) {
          ivert = 0;
        }
        else if ( strcmp ( word, "]" ) == 0 ) {
          level = nlbrack - nrbrack;
        }
/*
  (indexedfaceset) MATERIALINDEX
*/
        else if ( leqi ( level_name[level-1], "INDEXEDFACESET" ) == TRUE ) {

          count = sscanf ( word, "%d%n", &jval, &width );

          if ( count > 0 ) {

            if ( jval == -1 ) {
              ivert = 0;
              face_num2 = face_num2 + 1;
            }
            else {

              if ( face_num2 < FACE_MAX ) {
                if ( jval != -1 ) {
                  jval = jval + cor3_num_old;
                }
                vertex_material[ivert][face_num2] = jval;
                ivert = ivert + 1;
              }
            }
          }
          else {
            bad_num = bad_num + 1;
            printf ( "Bad data %s\n", word );
          }
        } 
/*
  (indexedlineset) MATERIALINDEX
*/
        else if ( leqi ( level_name[level-1], "INDEXEDLINESET" ) == TRUE ) {

          count = sscanf ( word, "%d%n", &jval, &width );

          if ( count > 0 ) {

            if ( line_num2 < LINES_MAX ) {
              if ( jval != -1 ) {
                jval = jval + cor3_num_old;
              }
              line_material[line_num2] = jval;
              line_num2 = line_num2 + 1;
            }
          }
          else {
            bad_num = bad_num + 1;
            printf ( "Bad data %s\n", word );
          }
        }
        else {
          count = sscanf ( word, "%d%n", &jval, &width );

          if ( count > 0 ) {
          }
          else {
            bad_num = bad_num + 1;
            printf ( "Bad data %s\n", word );
          }
        }
      }
/*
  MATRIXTRANSFORM.
*/
      else if ( leqi ( level_name[level], "MATRIXTRANSFORM" ) == TRUE ) {

        if ( strcmp ( word, "{" ) == 0 ) {
        }
        else if ( strcmp ( word, "}" ) == 0 ) {
          level = nlbrack - nrbrack;
        }
        else if ( leqi ( word, "MATRIX" ) == TRUE ) {
          icol = -1;
          irow = 0;
        }
        else {

          count = sscanf ( word, "%f%n", &rval, &width );

          if ( count > 0 ) {

            icol = icol + 1;
            if ( icol > 3 ) {
              icol = 0;
              irow = irow + 1;
              if ( irow > 3 ) {
                irow = 0;
              }
            }

            transform_matrix[irow][icol] = rval;
          }

        }
      }
/*
  NORMAL
  The field "VECTOR" may be followed by three numbers,
  (handled here),  or by a square bracket, and sets of three numbers.
*/
      else if ( leqi ( level_name[level], "NORMAL" ) == TRUE ) {
/*
  (vertexproperty) NORMAL
*/
        if ( leqi ( level_name[level-1], "VERTEXPROPERTY" ) == TRUE ) {

          if ( strcmp ( word, "[" ) == 0 ) {
            ixyz = 0;
          }
          else if ( strcmp ( word, "]" ) == 0 ) {
            level = nlbrack - nrbrack;
          }
          else {
  
            count = sscanf ( word, "%f%n", &rval, &width );

            if ( count > 0 ) {

              if ( inormface < FACE_MAX ) {
                face_normal[ixyz][inormface] = rval;
              }

              ixyz = ixyz + 1;
              if ( ixyz > 2 ) {
                ixyz = 0;
                inormface = inormface + 1;
              }
            }
          }
        }
/*
  (anythingelse) NORMAL
*/
        else {

          if ( strcmp ( word, "{" ) == 0 ) {
            ixyz = 0;
          }
          else if ( strcmp ( word, "}" ) == 0 ) {
            level = nlbrack - nrbrack;
          }
          else if ( leqi ( word, "VECTOR" ) == TRUE ) {
          }
          else {

            count = sscanf ( word, "%f%n", &rval, &width );

            if ( count > 0 ) {

/*  COMMENTED OUT

              if ( nfnorm < FACE_MAX ) {
                normal[ixyz][nfnorm] = rval;
              }

*/
              ixyz = ixyz + 1;
              if ( ixyz > 2 ) {
                ixyz = 0;
              }
            }
            else {
              bad_num = bad_num + 1;
              printf ( "Bad data %s\n", word );
            }
          }
        }
      }
/*
  NORMALBINDING
  Read, but ignore
*/
      else if ( leqi ( level_name[level], "NORMALBINDING" ) == TRUE ) {

        if ( strcmp ( word, "{" ) == 0 ) {
        }
        else if ( strcmp ( word, "}" ) == 0 ) {
          level = nlbrack - nrbrack;
        }
        else if ( leqi ( word, "VALUE" ) == TRUE ) {
          count = sscanf ( next, "%s%n", normal_binding, &width );
          next = next + width;
        }
        else {
          count = sscanf ( word, "%f%n", &rval, &width );

          if ( count > 0 ) {
          }
          else {
            bad_num = bad_num + 1;
            printf ( "Bad data %s\n", word );
          }
        }
      }
/*
  NORMALINDEX
*/
      else if ( leqi ( level_name[level], "NORMALINDEX" ) == TRUE ) {
/*
  (indexedtrianglestripset) NORMALINDEX
*/
        if ( leqi ( level_name[level-1], "INDEXEDTRIANGLESTRIPSET" ) == TRUE ) {
          count = sscanf ( word, "%d%n", &jval, &width );

          if ( count > 0 ) {
          }
          else if ( strcmp ( word, "[" ) == 0 ) {
          }
          else if ( strcmp ( word, "]" ) == 0 ) {
          }
        }
/*
  (anythingelse) NORMALINDEX
*/
        else {

          if ( strcmp ( word, "[" ) == 0 ) {
            ivert = 0;
          }
          else if ( strcmp ( word, "]" ) == 0 ) {
            level = nlbrack - nrbrack;
          }
          else {

            count = sscanf ( word, "%d%n", &jval, &width );

            if ( count > 0 ) {
              if ( jval == -1 ) {
                ivert = 0;
                iface_num = iface_num + 1;
              }
              else {
                if ( iface_num < FACE_MAX ) {
                  for ( i = 0; i < 3; i++ ){
                    vertex_normal[i][ivert][iface_num] = normal_temp[i][jval];
                  }
                  ivert = ivert + 1;
                }
              }
            }
            else {
              bad_num = bad_num + 1;
              printf ( "Bad data %s\n", word );
            }
          }
        }
      }
/*
  (coordinate3) POINT
*/
      else if ( leqi ( level_name[level], "POINT" ) == TRUE ) {

        if ( leqi ( level_name[level-1], "COORDINATE3" ) == TRUE ) {

          if ( strcmp ( word, "[" ) == 0 ) {
            ixyz = 0;
            cor3_num_old = cor3_num;
          }
          else if ( strcmp ( word, "]" ) == 0 ) {
            level = nlbrack - nrbrack;
          }
          else {

            count = sscanf ( word, "%f%n", &rval, &width );

            if ( count > 0 ) {

              if ( cor3_num < COR3_MAX ) {
                xvec[ixyz] = rval;
              }

              ixyz = ixyz + 1;

              if ( ixyz == 3 ) {

                ixyz = 0;
 
                tmat_mxp ( transform_matrix, xvec, xvec );

                cor3[0][cor3_num] = xvec[0];
                cor3[1][cor3_num] = xvec[1];
                cor3[2][cor3_num] = xvec[2];

                cor3_num = cor3_num + 1;

                continue;
              }
            }
            else {
              bad_num = bad_num + 1;
              break;
            }
          }
        }
/*
  (texturecoodinate2) POINT
*/
        else if ( leqi ( level_name[level-1], "TEXTURECOORDINATE2" ) == TRUE ) { 

          if ( strcmp ( word, "[" ) == 0 ) {
            iuv = 0;
            text_numure_temp = 0;
          }
          else if ( strcmp ( word, "]" ) == 0 ) {
            level = nlbrack - nrbrack;
          }
          else {

            count = sscanf ( word, "%f%n", &rval, &width );

            if ( count > 0 ) {

              texture_temp[iuv][text_numure_temp] = rval;

              iuv = iuv + 1;
              if ( iuv == 2 ) {
                iuv = 0;
                text_numure_temp = text_numure_temp + 1;
              }
            }
            else {
              printf ( "TextureCoordinate2 { Point [: Bad data\n" );
              bad_num = bad_num + 1;
              break;
            }
          }
        }
      }
/*
  RGB
*/
      else if ( leqi ( level_name[level],"RGB" ) == TRUE ) {
/*
  (basecolor) RGB
*/
        if ( leqi ( level_name[level-1], "BASECOLOR" ) == TRUE ) {

          if ( strcmp ( word, "[" ) == 0 ) {
            icolor = 0;
          }
          else if ( strcmp ( word, "]" ) == 0 ) {
            level = nlbrack - nrbrack;
          }
          else {

            count = sscanf ( word, "%f%n", &rval, &width );
  
            if ( count > 0 ) {

              rgbcolor[icolor][color_num] = rval;
              icolor = icolor + 1;

              if ( icolor == 3 ) {
                icolor = 0;
                color_num = color_num + 1;
              }
            }
            else {
              bad_num = bad_num + 1;
              printf ( "Bad data %s\n", word );
            }
          }
        }
/*
  (anythingelse RGB)
*/
        else {

          printf ( "HALSBAND DES TODES!\n" );

          if ( strcmp ( word, "[" ) == 0 ) {
            icolor = 0;
            ivert = 0;
          }
          else if ( strcmp ( word, "]" ) == 0 ) {
            level = nlbrack - nrbrack;
          }
          else {

            count = sscanf ( word, "%f%n", &rval, &width );
  
            if ( count > 0 ) {
 
              if ( icface < FACE_MAX ) {

                vertex_rgb[icolor][ivert][icface] = rval;

                icolor = icolor + 1;
                if ( icolor == 3 ) {
                  icolor = 0;
                  color_num = color_num + 1;
                  ivert = ivert + 1;
                  if ( ivert == face_order[icface] ) {
                    ivert = 0;
                    icface = icface + 1;
                  }
                }
              }
            }
            else {
              bad_num = bad_num + 1;
              printf ( "Bad data %s\n", word );
            }
          }
        }

      }
/*
  SEPARATOR
*/
      else if ( leqi ( level_name[level], "SEPARATOR" ) == TRUE ) {

        if ( strcmp ( word, "{" ) == 0 ) {
        }
        else if ( strcmp ( word, "}" ) == 0 ) {
          level = nlbrack - nrbrack;
        }
        else {
        }
      }
/*
  SHAPEHINTS
  Read, but ignore.
*/
      else if ( leqi ( level_name[level], "SHAPEHINTS" ) == TRUE ) {

        if ( strcmp ( word, "{" ) == 0 ) {
        }
        else if ( strcmp ( word, "}" ) == 0 ) {
          level = nlbrack - nrbrack;
        }
        else if ( leqi ( word, "CREASEANGLE" ) == TRUE ) {

          count = sscanf ( next, "%f%n", &rval, &width );
          next = next + width;

          if ( count <= 0 ) {
            bad_num = bad_num + 1;
            printf ( "Bad data %s\n", word );
          }
        }
        else if ( leqi ( word, "FACETYPE" ) == TRUE ) {
          count = sscanf ( next, "%s%n", word, &width );
          next = next + width;
        }
        else if ( leqi ( word, "SHAPETYPE" ) == TRUE ) {
          count = sscanf ( next, "%s%n", word, &width );
          next = next + width;
        }
        else if ( leqi ( word, "VERTEXORDERING" ) == TRUE ) {
          count = sscanf ( next, "%s%n", word, &width );
          next = next + width;
        }
        else {
          bad_num = bad_num + 1;
          printf ( "Bad data %s\n", word );
        }
      }
/*
  TEXTURE2
*/
      else if ( leqi ( level_name[level], "TEXTURE2" ) == TRUE ) {

        if ( strcmp ( word, "{" ) == 0 ) {
        }
        else if ( strcmp ( word, "}" ) == 0 ) {
          level = nlbrack - nrbrack;
          texture_num = texture_num + 1;
        }
        else if ( leqi ( word, "BLENDCOLOR" ) == TRUE ) {
        }
/*
  NEED TO REMOVE QUOTES SURROUNDING TEXTURE NAME.
*/
        else if ( leqi ( word, "FILENAME" ) == TRUE ) {

          count = sscanf ( next, "%s%n", word, &width );
          next = next + width;

          strcpy ( texture_name[texture_num], word );

          i = 0;
          j = 0;
          do {
            c = texture_name[texture_num][i];
            i = i + 1;
            if ( c != '"' ) {
              texture_name[texture_num][j] = c;
              j = j + 1;
            }
          } while ( c != '\0' );

        }
        else if ( leqi ( word, "IMAGE" ) == TRUE ) {
        }
        else if ( leqi ( word, "MODEL" ) == TRUE ) {
          count = sscanf ( next, "%s%n", word, &width );
          next = next + width;
        }
        else if ( leqi ( word, "WRAPS" ) == TRUE ) {
          count = sscanf ( next, "%s%n", word, &width );
          next = next + width;
        }
        else if ( leqi ( word, "WRAPT" ) == TRUE ) {
          count = sscanf ( next, "%s%n", word, &width );
          next = next + width;
        }
        else {
        }
      }
/*
  TEXTURECOORDINATE2
*/
      else if ( leqi ( level_name[level], "TEXTURECOORDINATE2" ) == TRUE ) {

        if ( strcmp ( word, "{" ) == 0 ) {
        }
        else if ( strcmp ( word, "}" ) == 0 ) {
          level = nlbrack - nrbrack;
        }
        else if ( leqi ( word, "POINT" ) == TRUE ) {
        }
        else {
          bad_num = bad_num + 1;
          printf ( "TEXTURECOORDINATE2: Bad data %s\n", word );
        }
      }
/*
  TEXTURECOORDINATEBINDING
*/
      else if ( leqi ( level_name[level], "TEXTURECOORDINATEBINDING" ) == TRUE ) {

        if ( strcmp ( word, "{" ) == 0 ) {
        }
        else if ( strcmp ( word, "}" ) == 0 ) {
          level = nlbrack - nrbrack;
        }
        else if ( leqi ( word, "VALUE" ) == TRUE ) {
          count = sscanf ( next, "%s%n", texture_binding, &width );
          next = next + width;
        }
        else {
          bad_num = bad_num + 1;
          printf ( "Bad data %s\n", word );
        }
      }
/*
  TEXTURECOORDINDEX
*/
      else if ( leqi ( level_name[level], "TEXTURECOORDINDEX" ) == TRUE ) {

        if ( strcmp ( word, "[" ) == 0 ) {
          ivert = 0;
          iface_num = 0;
        }
        else if ( strcmp ( word, "]" ) == 0 ) {
          level = nlbrack - nrbrack;
        }
        else {

          count = sscanf ( word, "%d%n", &jval, &width );

          if ( count > 0 ) {

            if ( jval == - 1 ) {
              ivert = 0;
            }
            else {

              if ( iface_num < FACE_MAX ) {
                vertex_tex_uv[0][ivert][iface_num] = texture_temp[0][jval];
                vertex_tex_uv[1][ivert][iface_num] = texture_temp[1][jval];
              }
  
              ivert = ivert + 1;

              if ( ivert == face_order[iface_num] ) {
                ivert = 0;
                iface_num = iface_num + 1;
              }
            }

          }
          else {
            bad_num = bad_num + 1;
            printf ( "Bad data %s\n", word );
          }

        }
      }
/*
  UKNOTVECTOR
*/
      else if ( leqi ( level_name[level], "UKNOTVECTOR" ) == TRUE ) {

        if ( strcmp ( word, "[" ) == 0 ) {
          continue;
        }
        else if ( strcmp ( word, "]" ) == 0 ) {
          level = nlbrack - nrbrack;
          continue;
        }
        else {
          count = sscanf ( word, "%d%n", &jval, &width );
        }
      }
/*
  VECTOR
*/
      else if ( leqi ( level_name[level], "VECTOR" ) == TRUE ) {
        if ( strcmp ( word, "[" ) == 0 ) {
        }
        else if ( strcmp ( word, "]" ) == 0 ) {
          level = nlbrack - nrbrack;
        }
/*
  (normal) VECTOR
*/
        else if ( leqi ( level_name[level-1], "NORMAL" ) == TRUE ) {

          count = sscanf ( word, "%f%n", &rval, &width );

          if ( count > 0 ) {

            if ( normal_num_temp < ORDER_MAX * FACE_MAX ) {
              normal_temp[ixyz][normal_num_temp] = rval;
              ixyz = ixyz + 1;
              if ( ixyz == 3 ) {
                ixyz = 0;
                normal_num_temp = normal_num_temp + 1;
              }
            }
          }
          else {
            bad_num = bad_num + 1;
            printf ( "NORMAL VECTOR: bad data %s\n", word );
          }
        }
      }
/*
  (vertexproperty) VERTEX
*/
      else if ( leqi ( level_name[level], "VERTEX" ) == TRUE ) {

        if ( leqi ( level_name[level-1], "VERTEXPROPERTY" ) == TRUE ) {

          if ( strcmp ( word, "[" ) == 0 ) {
            ixyz = 0;
            cor3_num_old = cor3_num;
          }
          else if ( strcmp ( word, "]" ) == 0 ) {
            level = nlbrack - nrbrack;
          }
          else {
            count = sscanf ( word, "%f%n", &rval, &width );

            if ( count > 0 ) {
 
              if ( cor3_num < COR3_MAX ) {
                cor3[ixyz][cor3_num] = rval;
              }
              ixyz = ixyz + 1;
              if ( ixyz == 3 ) {
                ixyz = 0;
                cor3_num = cor3_num + 1;
              }

            }
            else {
              bad_num = bad_num + 1;
              printf ( "Bad data %s\n", word );
            }
          }
        }
      }
/*
  (indexedtrianglestripset) VERTEXPROPERTY
*/
      else if ( leqi ( level_name[level], "VERTEXPROPERTY" ) == TRUE ) {

        if ( strcmp ( word, "{" ) == 0 ) {
        }
        else if ( strcmp ( word, "}" ) == 0 ) {
          level = nlbrack - nrbrack;
        }
        else if ( leqi ( word, "VERTEX" ) == TRUE ) {
        }
        else if ( leqi ( word, "NORMAL" ) == TRUE ) {
          ixyz = 0;
        }
        else if ( leqi ( word, "MATERIALBINDING" ) == TRUE ) {
          count = sscanf ( next, "%s%n", word, &width );
          next = next + width;
        }
        else if ( leqi ( word, "NORMALBINDING" ) == TRUE ) {
          count = sscanf ( next, "%s%n", word, &width );
          next = next + width;
        }
        else {
          bad_num = bad_num + 1;
          printf ( "Bad data %s\n", word );
        }
      }
/*
  VKNOTVECTOR
*/
      else if ( leqi ( level_name[level], "VKNOTVECTOR" ) == TRUE ) {

        if ( strcmp ( word, "[" ) == 0 ) {
          continue;
        }
        else if ( strcmp ( word, "]" ) == 0 ) {
          level = nlbrack - nrbrack;
          continue;
        }
        else {
          count = sscanf ( word, "%d%n", &jval, &width );
        }
      }
/*
  Any other word:
*/
      else {
      }
    }
  }
/*
  Reset the transformation matrix to the identity,
  because, presumably, we've applied it by now.
*/
  tmat_init ( transform_matrix );

  return SUCCESS;
}
/******************************************************************************/

int iv_write ( FILE *fileout )

/******************************************************************************/

/*
  Purpose:
   
    IV_WRITE writes graphics information to an Inventor file.

  Modified:

    29 June 1999

  Author:
 
    John Burkardt
*/
{
  int icor3;
  int iface;
  int itemp;
  int ivert;
  int j;
  int length;
  int text_num;

  text_num = 0;

  fprintf ( fileout, "#Inventor V2.0 ascii\n" );
  fprintf ( fileout, "\n" );
  fprintf ( fileout, "Separator {\n" );
  fprintf ( fileout, "  Info {\n" );
  fprintf ( fileout, "    string \"%s generated by IVCON.\"\n", fileout_name );
  fprintf ( fileout, "    string \"Original data in file %s.\"\n", filein_name );
  fprintf ( fileout, "  }\n" );
  fprintf ( fileout, "  Separator {\n" );
  text_num = text_num + 8;
/*
  LightModel:

    BASE_COLOR ignores light sources, and uses only diffuse color
      and transparency.  Even without normal vector information,
      the object will show up.  However, you won't get shadow
      and lighting effects.

    PHONG uses the Phong lighting model, accounting for light sources
      and surface orientation.  This is the default.  I believe
      you need accurate normal vector information in order for this
      option to produce nice pictures.

    DEPTH ignores light sources, and calculates lighting based on
      the location of the object within the near and far planes
      of the current camera's view volume.
*/
  fprintf ( fileout, "    LightModel {\n" );
  fprintf ( fileout, "      model PHONG\n" );
  fprintf ( fileout, "    }\n" );
  text_num = text_num + 3;
/*
  Transformation matrix.
*/
  fprintf ( fileout, "    MatrixTransform { matrix\n" );
  fprintf ( fileout, "      %f %f %f %f\n", transform_matrix[0][0],
    transform_matrix[0][1], transform_matrix[0][2], transform_matrix[0][3] );
  fprintf ( fileout, "      %f %f %f %f\n", transform_matrix[1][0],
    transform_matrix[1][1], transform_matrix[1][2], transform_matrix[1][3] );
  fprintf ( fileout, "      %f %f %f %f\n", transform_matrix[2][0],
    transform_matrix[2][1], transform_matrix[2][2], transform_matrix[2][3] );
  fprintf ( fileout, "      %f %f %f %f\n", transform_matrix[3][0],
    transform_matrix[3][1], transform_matrix[3][2], transform_matrix[3][3] );
  fprintf ( fileout, "    }\n" );
  text_num = text_num + 6;
/*
  Material.
*/
  fprintf ( fileout, "    Material {\n" );
  fprintf ( fileout, "      ambientColor  0.2 0.2 0.2\n" );
  fprintf ( fileout, "      diffuseColor  0.8 0.8 0.8\n" );
  fprintf ( fileout, "      emissiveColor 0.0 0.0 0.0\n" );
  fprintf ( fileout, "      specularColor 0.0 0.0 0.0\n" );
  fprintf ( fileout, "      shininess     0.2\n" );
  fprintf ( fileout, "      transparency  0.0\n" );
  fprintf ( fileout, "    }\n" );
  text_num = text_num + 8;
/*
  MaterialBinding
*/
  fprintf ( fileout, "    MaterialBinding {\n" );
  fprintf ( fileout, "      value PER_VERTEX_INDEXED\n" );
  fprintf ( fileout, "    }\n" );
  text_num = text_num + 3;
/*
  NormalBinding

    PER_VERTEX promises that we will write a list of normal vectors
    in a particular order, namely, the normal vectors for the vertices
    of the first face, then the second face, and so on.

    PER_VERTEX_INDEXED promises that we will write a list of normal vectors,
    and then, as part of the IndexedFaceSet, we will give a list of
    indices referencing this normal vector list.
*/
  fprintf ( fileout, "    NormalBinding {\n" );
  fprintf ( fileout, "      value PER_VERTEX_INDEXED\n" );
  fprintf ( fileout, "    }\n" );
  text_num = text_num + 3;
/*
  Texture2.

  FLAW: We can only handle on texture right now.
*/
  if ( texture_num > 0 ) {
    fprintf ( fileout, "    Texture2 {\n" );
    fprintf ( fileout, "      filename \"%s\"\n", texture_name[0] );
    fprintf ( fileout, "      wrapS       REPEAT\n" );
    fprintf ( fileout, "      wrapT       REPEAT\n" );
    fprintf ( fileout, "      model       MODULATE\n" );
    fprintf ( fileout, "      blendColor  0.0 0.0 0.0\n" );
    fprintf ( fileout, "    }\n" );
    text_num = text_num + 7;
  }
/*
  TextureCoordinateBinding
*/
  fprintf ( fileout, "    TextureCoordinateBinding {\n" );
  fprintf ( fileout, "      value PER_VERTEX_INDEXED\n" );
  fprintf ( fileout, "    }\n" );
  text_num = text_num + 3;
/*
  ShapeHints
*/
  fprintf ( fileout, "    ShapeHints {\n" );
  fprintf ( fileout, "      vertexOrdering COUNTERCLOCKWISE\n" );
  fprintf ( fileout, "      shapeType UNKNOWN_SHAPE_TYPE\n" );
  fprintf ( fileout, "      faceType CONVEX\n" );
  fprintf ( fileout, "      creaseAngle 6.28319\n" );
  fprintf ( fileout, "    }\n" );
  text_num = text_num + 6;
/*
  Point coordinates.
*/
  fprintf ( fileout, "    Coordinate3 {\n" );
  fprintf ( fileout, "      point [\n" );
  text_num = text_num + 2;

  for ( j = 0; j < cor3_num; j++ ) {
    fprintf ( fileout, "        %f %f %f,\n", cor3[0][j], cor3[1][j], cor3[2][j] );
    text_num = text_num + 1;
  }
  fprintf ( fileout, "      ]\n" );
  fprintf ( fileout, "    }\n" );
  text_num = text_num + 2;
/*
  Texture coordinates.
*/
  fprintf ( fileout, "    TextureCoordinate2 {\n" );
  fprintf ( fileout, "      point [\n" );
  text_num = text_num + 2;

  for ( iface = 0; iface < face_num; iface++ ) {
    for ( ivert = 0; ivert < face_order[iface]; ivert++ ) {
      fprintf ( fileout, "        %f %f,\n", vertex_tex_uv[0][ivert][iface], 
        vertex_tex_uv[1][ivert][iface] );
      text_num = text_num + 1;
    }
  }
  fprintf ( fileout, "      ]\n" );
  fprintf ( fileout, "    }\n" );
  text_num = text_num + 2;
/*
  BaseColor.
*/
  if ( color_num > 0 ) {

    fprintf ( fileout, "    BaseColor {\n" );
    fprintf ( fileout, "      rgb [\n" );
    text_num = text_num + 2;

    for ( j = 0; j < color_num; j++ ) {
      fprintf ( fileout, "        %f %f %f,\n", rgbcolor[0][j], rgbcolor[1][j], 
        rgbcolor[2][j] );
      text_num = text_num + 1;
    }

    fprintf ( fileout, "      ]\n" );
    fprintf ( fileout, "    }\n" );
    text_num = text_num + 2;
  }
/*
  Normal vectors.
    Use the normal vectors associated with nodes.
*/
  if ( face_num > 0 ) {

    fprintf ( fileout, "    Normal { \n" );
    fprintf ( fileout, "      vector [\n" );
    text_num = text_num + 2;

    for ( icor3 = 0; icor3 < cor3_num; icor3++ ) {
      fprintf ( fileout, "        %f %f %f,\n", 
        cor3_normal[0][icor3], 
        cor3_normal[1][icor3], 
        cor3_normal[2][icor3] );
      text_num = text_num + 1;
    }

    fprintf ( fileout, "      ]\n" );
    fprintf ( fileout, "    }\n" );
    text_num = text_num + 2;
  }
/*
  IndexedLineSet
*/
  if ( line_num > 0 ) {

    fprintf ( fileout, "    IndexedLineSet {\n" );
/*
  IndexedLineSet coordIndex
*/
    fprintf ( fileout, "      coordIndex [\n" );
    text_num = text_num + 2;

    length = 0;

    for ( j = 0; j < line_num; j++ ) {

      if ( length == 0 ) {
        fprintf ( fileout, "       " );
      }

      fprintf ( fileout, " %d,", line_dex[j] );
      length = length + 1;

      if ( line_dex[j] == -1 || length >= 10 || j == line_num-1 ) {
        fprintf ( fileout, "\n" );
        text_num = text_num + 1;
        length = 0;
      }
    }

    fprintf ( fileout, "      ]\n" );
    text_num = text_num + 1;
/*
  IndexedLineSet materialIndex.
*/
    fprintf ( fileout, "      materialIndex [\n" );
    text_num = text_num + 1;

    length = 0;

    for ( j = 0; j < line_num; j++ ) {

      if ( length == 0 ) {
        fprintf ( fileout, "       " );
      }

      fprintf ( fileout, " %d,", line_material[j] );
      length = length + 1;

      if ( line_material[j] == -1 || length >= 10 || j == line_num-1 ) {
        fprintf ( fileout, "\n" );
        text_num = text_num + 1;
        length = 0;
      }
    }

    fprintf ( fileout, "      ]\n" );
    fprintf ( fileout, "    }\n" );
    text_num = text_num + 2;
  }
/*
  IndexedFaceSet.
*/
  if ( face_num > 0 ) {

    fprintf ( fileout, "    IndexedFaceSet {\n" );
    fprintf ( fileout, "      coordIndex [\n" );
    text_num = text_num + 2;

    for ( iface = 0; iface < face_num; iface++ ) {

      fprintf ( fileout, "       " );

      for ( ivert = 0; ivert < face_order[iface]; ivert++ ) {
        fprintf ( fileout, " %d,", face[ivert][iface] );
      }
      fprintf ( fileout, " -1,\n" );
      text_num = text_num + 1;
    }

    fprintf ( fileout, "      ]\n" );
    text_num = text_num + 1;
/*
  IndexedFaceSet normalIndex
*/
    fprintf ( fileout, "      normalIndex [\n" );
    text_num = text_num + 1;

    for ( iface = 0; iface < face_num; iface++ ) {

      fprintf ( fileout, "       " );

      for ( ivert = 0; ivert < face_order[iface]; ivert++ ) {
        fprintf ( fileout, " %d,", face[ivert][iface] );
      }
      fprintf ( fileout, " -1,\n" );
      text_num = text_num + 1;
    }
    fprintf ( fileout, "      ]\n" );
    text_num = text_num + 1;
/*
  IndexedFaceSet materialIndex
*/
    fprintf ( fileout, "      materialIndex [\n" );
    text_num = text_num + 1;

    for ( iface = 0; iface < face_num; iface++ ) {

      fprintf ( fileout, "       " );

      for ( ivert = 0; ivert < face_order[iface]; ivert++ ) {
        fprintf ( fileout, " %d,", vertex_material[ivert][iface] );
      }
      fprintf ( fileout, " -1,\n" );
      text_num = text_num + 1;
    }

    fprintf ( fileout, "      ]\n" );
    text_num = text_num + 1;
/*
  IndexedFaceSet textureCoordIndex
*/
    fprintf ( fileout, "      textureCoordIndex [\n" );
    text_num = text_num + 1;

    itemp = 0;

    for ( iface = 0; iface < face_num; iface++ ) {

      fprintf ( fileout, "       " );

      for ( ivert = 0; ivert < face_order[iface]; ivert++ ) {
        fprintf ( fileout, " %d,", itemp );
        itemp = itemp + 1;
      }
      fprintf ( fileout, " -1,\n" );
      text_num = text_num + 1;
    }

    fprintf ( fileout, "      ]\n" );

    fprintf ( fileout, "    }\n" );
    text_num = text_num + 2;
  }
/*
  Close up the Separator nodes.
*/
  fprintf ( fileout, "  }\n" );
  fprintf ( fileout, "}\n" );
  text_num = text_num + 2;
/*
  Report.
*/
  printf ( "\n" );
  printf ( "IV_WRITE - Wrote %d text lines;\n", text_num );

  return SUCCESS;
}
/******************************************************************************/

int ivec_max ( int n, int *a )

/******************************************************************************/

/*
  Purpose:

    IVEC_MAX returns the maximum element in an integer array.

  Modified:

    09 October 1998

  Author:

    John Burkardt
*/
{
  int  i;
  int *ia;
  int  imax;

  if ( n <= 0 ) {
    imax = 0;
  }
  else {
    ia = a;
    imax = *ia;
    for ( i = 1; i < n; i++ ) {
      ia = ia + 1;
      if ( imax < *ia ) {
        imax = *ia;
      }
    }
  }
  return imax;
}
/******************************************************************************/

int leqi ( char* string1, char* string2 )

/******************************************************************************/

/*
  Purpose:

    LEQI compares two strings for equality, disregarding case.

  Modified:

    15 September 1998

  Author:
 
    John Burkardt
*/
{
  int i;
  int nchar;
  int nchar1;
  int nchar2;

  nchar1 = strlen ( string1 );
  nchar2 = strlen ( string2 );

  if ( nchar1 < nchar2 ) {
    nchar = nchar1;
  }
  else {
    nchar = nchar2;
  }
/*
  The strings are not equal if they differ over their common length.
*/
  for ( i = 0; i < nchar; i++ ) {

    if ( toupper ( string1[i] ) != toupper ( string2[i] ) ) {
      return FALSE;
    }
  }
/*
  The strings are not equal if the longer one includes nonblanks
  in the tail.
*/
  if ( nchar1 > nchar ) {
    for ( i = nchar; i < nchar1; i++ ) {
      if ( string1[i] != ' ' ) {
        return FALSE;
      }
    } 
  }
  else if ( nchar2 > nchar ) {
    for ( i = nchar; i < nchar2; i++ ) {
      if ( string2[i] != ' ' ) {
        return FALSE;
      }
    } 
  }
  return TRUE;
}
/******************************************************************************/

long int long_int_read ( FILE *filein )

/******************************************************************************/

/*
  Purpose:

    LONG_INT_READ reads a long int from a binary file.

  Modified:
 
    24 May 1999

  Author:

    John Burkardt
*/
{
  union {
    long int yint;
    char ychar[4];
  } y;

  if ( byte_swap == TRUE ) {
    y.ychar[3] = fgetc ( filein );
    y.ychar[2] = fgetc ( filein );
    y.ychar[1] = fgetc ( filein );
    y.ychar[0] = fgetc ( filein );
  }
  else {
    y.ychar[0] = fgetc ( filein );
    y.ychar[1] = fgetc ( filein );
    y.ychar[2] = fgetc ( filein );
    y.ychar[3] = fgetc ( filein );
  }

  return y.yint;
}
/******************************************************************************/

int long_int_write ( FILE *fileout, long int int_val )

/******************************************************************************/

/*
  Purpose:

    LONG_INT_WRITE writes a long int to a binary file.

  Modified:
 
    14 October 1998

  Author:

    John Burkardt
*/
{
  union {
    long int yint;
    char ychar[4];
  } y;

  y.yint = int_val;

  if ( byte_swap == TRUE ) {
    fputc ( y.ychar[3], fileout );
    fputc ( y.ychar[2], fileout );
    fputc ( y.ychar[1], fileout );
    fputc ( y.ychar[0], fileout );
  }
  else {
    fputc ( y.ychar[0], fileout );
    fputc ( y.ychar[1], fileout );
    fputc ( y.ychar[2], fileout );
    fputc ( y.ychar[3], fileout );
  }

  return 4;
}
/******************************************************************************/

void news ( void )

/******************************************************************************/

/*
  Purpose:

    NEWS reports the program change history.

  Modified:
 
    26 September 1999

  Author:
 
    John Burkardt
*/
{
  printf ( "\n" );
  printf ( "Recent changes:\n" );
  printf ( "\n" );
  printf ( "  04 July 2000\n" );
  printf ( "    Added preliminary XGL_WRITE.\n" );
  printf ( "  26 September 1999\n" );
  printf ( "    After ASE_READ, call NODE_TO_VERTEX_MAT and VERTEX_TO_FACE_MATERIAL.\n" );
  printf ( "  27 July 1999\n" );
  printf ( "    Corrected TMAT_ROT_VECTOR.\n" );
  printf ( "  17 July 1999\n" );
  printf ( "    Added null edge and face deletion.\n" );
  printf ( "    Corrected a string problem in SMF_READ.\n" );
  printf ( "  03 July 1999\n" );
  printf ( "    Fixed a problem with BINDING variables in SMF_READ.\n" );
  printf ( "  02 July 1999\n" );
  printf ( "    Added limited texture support in 3DS/IV.\n" );
  printf ( "  26 June 1999\n" );
  printf ( "    BYU_READ added.\n" );
  printf ( "  25 June 1999\n" );
  printf ( "    BYU_WRITE added.\n" );
  printf ( "  22 June 1999\n" );
  printf ( "    TRIB_READ added.\n" );
  printf ( "  16 June 1999\n" );
  printf ( "    TRIB_WRITE Greg Hood binary triangle output routine added.\n" );
  printf ( "  10 June 1999\n" );
  printf ( "    TRIA_WRITE Greg Hood ASCII triangle output routine added.\n" );
  printf ( "  09 June 1999\n" );
  printf ( "    TEC_WRITE TECPLOT output routine added.\n" );
  printf ( "    IV_READ and IV_WRITE use TRANSFORM_MATRIX now.\n" );
  printf ( "  26 May 1999\n" );
  printf ( "    LINE_PRUNE option added for VLA_WRITE.\n" );
  printf ( "  24 May 1999\n" );
  printf ( "    Added << command to append new graphics data to old.\n" );
  printf ( "    Stuck in first draft STLB_READ/STLB_WRITE routines.\n" );
  printf ( "    STLA_WRITE and STLB_WRITE automatically decompose \n" );
  printf ( "      non-triangular faces before writing.\n" );
  printf ( "  23 May 1999\n" );
  printf ( "    Stuck in first draft WRL_WRITE routine.\n" );
  printf ( "  22 May 1999\n" );
  printf ( "    Faces converted to lines before calling VLA_WRITE.\n" );
  printf ( "    Added UCD_WRITE.\n" );
  printf ( "    Added MATERIAL/PATCH/TAGGEDPOINTS fields in HRC_READ.\n" );
  printf ( "  17 May 1999\n" );
  printf ( "    Updated SMF_WRITE, SMF_READ to match code in IVREAD.\n" );
  printf ( "    Added transformation matrix routines.\n" );
  printf ( "  16 May 1999\n" );
  printf ( "    Zik Saleeba improved DXF support to handle polygons.\n" );
  printf ( "  15 April 1999\n" );
  printf ( "    Zik Saleeba added Golgotha GMOD file format support.\n" );
  printf ( "  03 December 1998\n" );
  printf ( "    Set up simple hooks in TDS_READ_MATERIAL_SECTION.\n" );
  printf ( "  02 December 1998\n" );
  printf ( "    Set up simple hooks for texture map names.\n" );
  printf ( "  19 November 1998\n" );
  printf ( "    IV_WRITE uses PER_VERTEX normal binding.\n" );
  printf ( "  18 November 1998\n" );
  printf ( "    Added node normals.\n" );
  printf ( "    Finally added the -RN option.\n" );
  printf ( "  17 November 1998\n" );
  printf ( "    Added face node ordering reversal option.\n" );
  printf ( "  20 October 1998\n" );
  printf ( "    Added DATA_REPORT.\n" );
  printf ( "  19 October 1998\n" );
  printf ( "    SMF_READ and SMF_WRITE added.\n" );
  printf ( "  16 October 1998\n" );
  printf ( "    Fixing a bug in IV_READ that chokes on ]} and other\n" );
  printf ( "    cases where brackets aren't properly spaced.\n" );
  printf ( "  11 October 1998\n" );
  printf ( "    Added face subset selection option S.\n" );
  printf ( "  09 October 1998\n" );
  printf ( "    Reworking normal vector treatments.\n" );
  printf ( "    Synchronizing IVREAD and IVCON.\n" );
  printf ( "    POV_WRITE added.\n" );
  printf ( "  02 October 1998\n" );
  printf ( "    IVCON reproduces BOX.3DS and CONE.3DS exactly.\n" );
  printf ( "  30 September 1998\n" );
  printf ( "    IVCON compiled on the PC.\n" );
  printf ( "    Interactive BYTE_SWAP option added for binary files.\n" );
  printf ( "  25 September 1998\n" );
  printf ( "    OBJECT_NAME made available to store object name.\n" );
  printf ( "  23 September 1998\n" );
  printf ( "    3DS binary files can be written.\n" );
  printf ( "  15 September 1998\n" );
  printf ( "    3DS binary files can be read.\n" );
  printf ( "  01 September 1998\n" );
  printf ( "    COR3_RANGE, FACE_NORMAL_AVE added.\n" );
  printf ( "    Major modifications to normal vectors.\n" );
  printf ( "  24 August 1998\n" );
  printf ( "    HRC_READ added.\n" );
  printf ( "  21 August 1998\n" );
  printf ( "    TXT_WRITE improved.\n" );
  printf ( "  20 August 1998\n" );
  printf ( "    HRC_WRITE can output lines as linear splines.\n" );
  printf ( "  19 August 1998\n" );
  printf ( "    Automatic normal computation for OBJ files.\n" );
  printf ( "    Added normal vector computation.\n" );
  printf ( "    HRC_WRITE is working.\n" );
  printf ( "  18 August 1998\n" );
  printf ( "    IV_READ/IV_WRITE handle BASECOLOR RGB properly now.\n" );
  printf ( "    Improved treatment of face materials and normals.\n" );
  printf ( "  17 August 1998\n" );
  printf ( "    ORDER_MAX increased to 35.\n" );
  printf ( "    FACE_PRINT routine added.\n" );
  printf ( "    INIT_DATA routine added.\n" );
  printf ( "  14 August 1998\n" );
  printf ( "    IV_READ is working.\n" );
  printf ( "  13 August 1998\n" );
  printf ( "    ASE_WRITE is working.\n" );
  printf ( "    IV_WRITE is working.\n" );
  printf ( "  12 August 1998\n" );
  printf ( "    ASE_READ is working.\n" );
  printf ( "  10 August 1998\n" );
  printf ( "    DXF_WRITE is working.\n" );
  printf ( "    DXF_READ is working.\n" );
  printf ( "  27 July 1998\n" );
  printf ( "    Interactive mode is working.\n" );
  printf ( "    OBJ_READ is working.\n" );
  printf ( "  25 July 1998\n" );
  printf ( "    OBJ_WRITE is working.\n" );
  printf ( "  24 July 1998\n" );
  printf ( "    DATA_CHECK checks the input data.\n" );
  printf ( "    VLA_READ is working.\n" );
  printf ( "    VLA_WRITE is working.\n" );
  printf ( "  23 July 1998\n" );
  printf ( "    STL_WRITE is working.\n" );
  printf ( "  22 July 1998\n" );
  printf ( "    STL_READ is working.\n" );
  printf ( "    TXT_WRITE is working.\n" );
}
/**********************************************************************/

void node_to_vertex_material ( void )

/**********************************************************************/

/*
  Purpose:

    NODE_TO_VERTEX_MAT extends node material definitions to vertices.

  Discussion:

    A NODE is a point in space.
    A VERTEX is a node as used in a particular face.
    One node may be used as a vertex in several faces, or none.

  Modified:

    22 May 1999

  Author:

    John Burkardt
*/
{
  int iface;
  int ivert;
  int node;

  for ( iface = 0; iface < face_num; iface++ ) {
    for ( ivert = 0; ivert < face_order[iface]; ivert++ ) {
      node = face[ivert][iface];
      vertex_material[ivert][iface] = cor3_material[node];
    }
  }

  return;
}
/******************************************************************************/

int obj_read ( FILE *filein )

/******************************************************************************/

/*
  Purpose:
   
    OBJ_READ reads a Wavefront OBJ file.

  Example:

    #  magnolia.obj

    mtllib ./vp.mtl

    g
    v -3.269770 -39.572201 0.876128
    v -3.263720 -39.507999 2.160890
    ...
    v 0.000000 -9.988540 0.000000
    g stem
    s 1
    usemtl brownskn
    f 8 9 11 10
    f 12 13 15 14
    ...
    f 788 806 774

  Modified:

    20 October 1998

  Author:
 
    John Burkardt
*/
{
  int   count;
  int   i;
  int   ivert;
  char *next;
  char *next2;
  char *next3;
  int   node;
  int   vertex_normal_num;
  float r1;
  float r2;
  float r3;
  char  token[LINE_MAX_LEN];
  char  token2[LINE_MAX_LEN];
  int   width;
/* 
  Initialize. 
*/
  vertex_normal_num = 0;
/* 
  Read the next line of the file into INPUT. 
*/
  while ( fgets ( input, LINE_MAX_LEN, filein ) != NULL ) {

    text_num = text_num + 1;
/* 
  Advance to the first nonspace character in INPUT. 
*/
    for ( next = input; *next != '\0' && isspace(*next); next++ ) {
    }
/* 
  Skip blank lines and comments. 
*/

    if ( *next == '\0' ) {
      continue;
    }

    if ( *next == '#' || *next == '$' ) {
      comment_num = comment_num + 1;
      continue;
    }
/* 
  Extract the first word in this line. 
*/
    sscanf ( next, "%s%n", token, &width );
/* 
  Set NEXT to point to just after this token. 
*/

    next = next + width;
/*
  BEVEL
  Bevel interpolation.
*/
    if ( leqi ( token, "BEVEL" ) == TRUE ) {
      continue;
    }
/*
  BMAT
  Basis matrix.
*/
    else if ( leqi ( token, "BMAT" ) == TRUE ) {
      continue;
    }
/*
  C_INTERP
  Color interpolation.
*/
    else if ( leqi ( token, "C_INTERP" ) == TRUE ) {
      continue;
    }
/*
  CON
  Connectivity between free form surfaces.
*/
    else if ( leqi ( token, "CON" ) == TRUE ) {
      continue;
    }
/*
  CSTYPE
  Curve or surface type.
*/
    else if ( leqi ( token, "CSTYPE" ) == TRUE ) {
      continue;
    }
/*
  CTECH
  Curve approximation technique.
*/
    else if ( leqi ( token, "CTECH" ) == TRUE ) {
      continue;
    }
/*
  CURV
  Curve.
*/
    else if ( leqi ( token, "CURV" ) == TRUE ) {
      continue;
    }
/*
  CURV2
  2D curve.
*/
    else if ( leqi ( token, "CURV2" ) == TRUE ) {
      continue;
    }
/*
  D_INTERP
  Dissolve interpolation.
*/
    else if ( leqi ( token, "D_INTERP" ) == TRUE ) {
      continue;
    }
/*
  DEG
  Degree.
*/
    else if ( leqi ( token, "DEG" ) == TRUE ) {
      continue;
    }
/*
  END
  End statement.
*/
    else if ( leqi ( token, "END" ) == TRUE ) {
      continue;
    }
/*  
  F V1 V2 V3
    or
  F V1/VT1/VN1 V2/VT2/VN2 ...
    or
  F V1//VN1 V2//VN2 ...

  Face.
  A face is defined by the vertices.
  Optionally, slashes may be used to include the texture vertex
  and vertex normal indices.

  OBJ line node indices are 1 based rather than 0 based.
  So we have to decrement them before loading them into FACE.
*/

    else if ( leqi ( token, "F" ) == TRUE ) {

      ivert = 0;
      face_order[face_num] = 0;
/*
  Read each item in the F definition as a token, and then
  take it apart.
*/
      for ( ;; ) {

        count = sscanf ( next, "%s%n", token2, &width );
        next = next + width;
 
        if ( count != 1 ) {
          break;
        }
 
        count = sscanf ( token2, "%d%n", &node, &width );
        next2 = token2 + width;

        if ( count != 1 ) {
          break;
        }

        if ( ivert < ORDER_MAX && face_num < FACE_MAX ) {
          face[ivert][face_num] = node-1;
          vertex_material[ivert][face_num] = 0;
          face_order[face_num] = face_order[face_num] + 1;
        } 
/*
  If there's a slash, skip to the next slash, and extract the
  index of the normal vector.
*/
        if ( *next2 == '/' ) {

          for ( next3 = next2 + 1; next3 < token2 + LINE_MAX_LEN; next3++ ) {

            if ( *next3 == '/' ) {
              next3 = next3 + 1;
              count = sscanf ( next3, "%d%n", &node, &width );

              node = node - 1;
              if ( 0 <= node && node < vertex_normal_num ) {
                for ( i = 0; i < 3; i++ ) {
                  vertex_normal[i][ivert][face_num] = normal_temp[i][node];
                }
              }
              break;
            }
          }
        }
        ivert = ivert + 1;
      } 
      face_num = face_num + 1;
    }

/*  
  G  
  Group name.
*/

    else if ( leqi ( token, "G" ) == TRUE ) {
      continue;
    }
/*
  HOLE
  Inner trimming hole.
*/
    else if ( leqi ( token, "HOLE" ) == TRUE ) {
      continue;
    }
/*  
  L  
  I believe OBJ line node indices are 1 based rather than 0 based.
  So we have to decrement them before loading them into LINE_DEX.
*/

    else if ( leqi ( token, "L" ) == TRUE ) {

      for ( ;; ) {

        count = sscanf ( next, "%d%n", &node, &width );
        next = next + width;

        if ( count != 1 ) {
          break;
        }

        if ( line_num < LINES_MAX  ) {
          line_dex[line_num] = node-1;
          line_material[line_num] = 0;
        } 
        line_num = line_num + 1;

      } 

      if ( line_num < LINES_MAX ) {
        line_dex[line_num] = -1;
        line_material[line_num] = -1;
      }
      line_num = line_num + 1;

    }

/*
  LOD
  Level of detail.
*/
    else if ( leqi ( token, "LOD" ) == TRUE ) {
      continue;
    }
/*
  MG
  Merging group.
*/
    else if ( leqi ( token, "MG" ) == TRUE ) {
      continue;
    }
/*
  MTLLIB
  Material library.
*/

    else if ( leqi ( token, "MTLLIB" ) == TRUE ) {
      continue;
    }
/*
  O
  Object name.
*/
    else if ( leqi ( token, "O" ) == TRUE ) {
      continue;
    }
/*
  P
  Point.
*/
    else if ( leqi ( token, "P" ) == TRUE ) {
      continue;
    }
/*
  PARM
  Parameter values.
*/
    else if ( leqi ( token, "PARM" ) == TRUE ) {
      continue;
    }
/*
  S  
  Smoothing group
*/
    else if ( leqi ( token, "S" ) == TRUE ) {
      continue;
    }
/*
  SCRV
  Special curve.
*/
    else if ( leqi ( token, "SCRV" ) == TRUE ) {
      continue;
    }
/*
  SHADOW_OBJ
  Shadow casting.
*/
    else if ( leqi ( token, "SHADOW_OBJ" ) == TRUE ) {
      continue;
    }
/*
  SP
  Special point.
*/
    else if ( leqi ( token, "SP" ) == TRUE ) {
      continue;
    }
/*
  STECH
  Surface approximation technique.
*/
    else if ( leqi ( token, "STECH" ) == TRUE ) {
      continue;
    }
/*
  STEP
  Stepsize.
*/
    else if ( leqi ( token, "CURV" ) == TRUE ) {
      continue;
    }
/*
  SURF
  Surface.
*/
    else if ( leqi ( token, "SURF" ) == TRUE ) {
      continue;
    }
/*
  TRACE_OBJ
  Ray tracing.
*/
    else if ( leqi ( token, "TRACE_OBJ" ) == TRUE ) {
      continue;
    }
/*
  TRIM
  Outer trimming loop.
*/
    else if ( leqi ( token, "TRIM" ) == TRUE ) {
      continue;
    }
/*
  USEMTL  
  Material name.
*/
    else if ( leqi ( token, "USEMTL" ) == TRUE ) {
      continue;
    }

/*
  V X Y Z W
  Geometric vertex.
  W is optional, a weight for rational curves and surfaces.
  The default for W is 1.
*/

    else if ( leqi ( token, "V" ) == TRUE ) {

      sscanf ( next, "%e %e %e", &r1, &r2, &r3 );

      if ( cor3_num < COR3_MAX ) {
        cor3[0][cor3_num] = r1;
        cor3[1][cor3_num] = r2;
        cor3[2][cor3_num] = r3;
      }

      cor3_num = cor3_num + 1;

    }
/*
  VN
  Vertex normals.
*/

    else if ( leqi ( token, "VN" ) == TRUE ) {

      sscanf ( next, "%e %e %e", &r1, &r2, &r3 );

      if ( vertex_normal_num < ORDER_MAX * FACE_MAX ) {
        normal_temp[0][vertex_normal_num] = r1;
        normal_temp[1][vertex_normal_num] = r2;
        normal_temp[2][vertex_normal_num] = r3;
      }

      vertex_normal_num = vertex_normal_num + 1;

    }
/*
  VT
  Vertex texture.
*/
    else if ( leqi ( token, "VT" ) == TRUE ) {
      continue;
    }
/*
  VP
  Parameter space vertices.
*/
    else if ( leqi ( token, "VP" ) == TRUE ) {
      continue;
    }
/*
  Unrecognized  
*/
    else {
      bad_num = bad_num + 1;
    }

  }
  return SUCCESS;
}
/******************************************************************************/

int obj_write ( FILE *fileout )

/******************************************************************************/

/*
  Purpose:
   
    OBJ_WRITE writes a Wavefront OBJ file.

  Example:

    #  magnolia.obj

    mtllib ./vp.mtl

    g
    v -3.269770 -39.572201 0.876128
    v -3.263720 -39.507999 2.160890
    ...
    v 0.000000 -9.988540 0.000000
    g stem
    s 1
    usemtl brownskn
    f 8 9 11 10
    f 12 13 15 14
    ...
    f 788 806 774

  Modified:

    01 September 1998

  Author:
 
    John Burkardt
*/
{
  int   i;
  int   iface;
  int   indexvn;
  int   ivert;
  int   k;
  int   new;
  int   text_num;
  float w;
/* 
  Initialize. 
*/
  text_num = 0;
  w = 1.0;

  fprintf ( fileout, "# %s created by IVCON.\n", fileout_name );
  fprintf ( fileout, "# Original data in %s.\n", filein_name );
  fprintf ( fileout, "\n" );
  fprintf ( fileout, "g %s\n", object_name );
  fprintf ( fileout, "\n" );

  text_num = text_num + 5;
/* 
  V: vertex coordinates. 
*/
  for ( i = 0; i < cor3_num; i++ ) {
    fprintf ( fileout, "v %f %f %f %f\n", 
      cor3[0][i], cor3[1][i], cor3[2][i], w );
    text_num = text_num + 1;
  }

/* 
  VN: Vertex face normal vectors. 
*/
  if ( face_num > 0 ) {
    fprintf ( fileout, "\n" );
    text_num = text_num + 1;
  }

  for ( iface = 0; iface < face_num; iface++ ) {

    for ( ivert = 0; ivert < face_order[iface]; ivert++ ) {

      fprintf ( fileout, "vn %f %f %f\n", vertex_normal[0][ivert][iface],
        vertex_normal[1][ivert][iface], vertex_normal[2][ivert][iface] );
      text_num = text_num + 1;
    }
  }
/* 
  F: faces. 
*/
  if ( face_num > 0 ) {
    fprintf ( fileout, "\n" );
    text_num = text_num + 1;
  }

  indexvn = 0;

  for ( iface = 0; iface < face_num; iface++ ) {

    fprintf ( fileout, "f" );
    for ( ivert = 0; ivert < face_order[iface]; ivert++ ) {
      indexvn = indexvn + 1;
      fprintf ( fileout, " %d//%d", face[ivert][iface]+1, indexvn );
    }
    fprintf ( fileout, "\n" );
    text_num = text_num + 1;
  }
/* 
  L: lines. 
*/
  if ( line_num > 0 ) {
    fprintf ( fileout, "\n" );
    text_num = text_num + 1;
  }

  new = TRUE;

  for ( i = 0; i < line_num; i++ ) {

    k = line_dex[i];

    if ( k == -1 ) {
      fprintf ( fileout, "\n" );
      text_num = text_num + 1;
      new = TRUE;
    }
    else {
      if ( new == TRUE ) {
        fprintf ( fileout, "l" );
        new = FALSE;
      }
      fprintf ( fileout, " %d", k+1 );
    }
    
  }

  fprintf ( fileout, "\n" );
  text_num = text_num + 1;
/*
  Report.
*/
  printf ( "\n" );
  printf ( "OBJ_WRITE - Wrote %d text lines.\n", text_num );

  return SUCCESS;
}
/******************************************************************************/

int pov_write ( FILE *fileout )

/******************************************************************************/

/*
  Purpose:

    POV_WRITE writes graphics information to a POV file.

  Example:

    // cone.pov created by IVCON.
    // Original data in cone.iv

    #version 3.0
    #include "colors.inc"
    #include "shapes.inc"
    global_settings { assumed_gamma 2.2 }

    camera {
     right < 4/3, 0, 0>
     up < 0, 1, 0 >
     sky < 0, 1, 0 >
     angle 20
     location < 0, 0, -300 >
     look_at < 0, 0, 0>
    }

    light_source { < 20, 50, -100 > color White }

    background { color SkyBlue }

    #declare RedText = texture {
      pigment { color rgb < 0.8, 0.2, 0.2> }
      finish { ambient 0.2 diffuse 0.5 }
    }

    #declare BlueText = texture {
      pigment { color rgb < 0.2, 0.2, 0.8> }
      finish { ambient 0.2 diffuse 0.5 }
    }
    mesh {
      smooth_triangle {
        < 0.29, -0.29, 0.0>, < 0.0, 0.0, -1.0 >,
        < 38.85, 10.03, 0.0>, < 0.0, 0.0, -1.0 >,
        < 40.21, -0.29, 0.0>, <  0.0, 0.0, -1.0 >
        texture { RedText } }
        ...
      smooth_triangle {
        <  0.29, -0.29, 70.4142 >, < 0.0,  0.0, 1.0 >,
        <  8.56,  -2.51, 70.4142 >, < 0.0,  0.0, 1.0 >,
        <  8.85, -0.29, 70.4142 >, < 0.0,  0.0, 1.0 >
        texture { BlueText } }
    }

  Modified:

    08 October 1998

  Author:

    John Burkardt
*/
{
  int i;
  int j;
  int jj;
  int jlo;
  int k;
  int text_num;

  text_num = 0;
  fprintf ( fileout,  "// %s created by IVCON.\n", fileout_name );
  fprintf ( fileout,  "// Original data in %s.\n", filein_name );
  text_num = text_num + 2;
/*
  Initial declarations.
*/
  fprintf ( fileout, "\n" );
  fprintf ( fileout, "#version 3.0\n" );
  fprintf ( fileout, "#include \"colors.inc\"\n" );
  fprintf ( fileout, "#include \"shapes.inc\"\n" );
  fprintf ( fileout, "global_settings { assumed_gamma 2.2 }\n" );
  fprintf ( fileout, "\n" );
  fprintf ( fileout, "camera {\n" );
  fprintf ( fileout, " right < 4/3, 0, 0>\n" );
  fprintf ( fileout, " up < 0, 1, 0 >\n" );
  fprintf ( fileout, " sky < 0, 1, 0 >\n" );
  fprintf ( fileout, " angle 20\n" );
  fprintf ( fileout, " location < 0, 0, -300 >\n" );
  fprintf ( fileout, " look_at < 0, 0, 0>\n" );
  fprintf ( fileout, "}\n" );
  fprintf ( fileout, "\n" );
  fprintf ( fileout, "light_source { < 20, 50, -100 > color White }\n" );
  fprintf ( fileout, "\n" );
  fprintf ( fileout, "background { color SkyBlue }\n" );

  text_num = text_num + 15;
/*
  Declare RGB textures.
*/
  fprintf ( fileout, "\n" );
  fprintf ( fileout, "#declare RedText = texture {\n" );
  fprintf ( fileout, "  pigment { color rgb < 0.8, 0.2, 0.2> }\n" );
  fprintf ( fileout, "  finish { ambient 0.2 diffuse 0.5 }\n" );
  fprintf ( fileout, "}\n" );
  fprintf ( fileout, "\n" );
  fprintf ( fileout, "#declare GreenText = texture {\n" );
  fprintf ( fileout, "  pigment { color rgb < 0.2, 0.8, 0.2> }\n" );
  fprintf ( fileout, "  finish { ambient 0.2 diffuse 0.5 }\n" );
  fprintf ( fileout, "}\n" );
  fprintf ( fileout, "\n" );
  fprintf ( fileout, "#declare BlueText = texture {\n" );
  fprintf ( fileout, "  pigment { color rgb < 0.2, 0.2, 0.8> }\n" );
  fprintf ( fileout, "  finish { ambient 0.2 diffuse 0.5 }\n" );
  fprintf ( fileout, "}\n" );
/*
  Write one big object.
*/
  fprintf ( fileout,  "mesh {\n" );
  text_num = text_num + 1;
/*
  Do the next face.
*/
  for ( i = 0; i < face_num; i++ ) {
/*
  Break the face up into triangles, anchored at node 1.
*/
    for ( jlo = 0; jlo < face_order[i] - 2; jlo++ ) {
      fprintf ( fileout, "  smooth_triangle {\n" );
      text_num = text_num + 1;

      for ( j = jlo; j < jlo + 3; j++ ) {

        if ( j == jlo ) {
          jj = 0;
        }
        else {
          jj = j;
        }

        k = face[jj][i];

        fprintf ( fileout, "<%f, %f, %f>, <%f, %f, %f>",
          cor3[0][k], cor3[1][k], cor3[2][k], 
          vertex_normal[0][jj][i], 
          vertex_normal[1][jj][i],
          vertex_normal[2][jj][i] );

        if ( j < jlo + 2 ) {
          fprintf ( fileout, ",\n" );
        }
        else {
          fprintf ( fileout, "\n" );
        }
        text_num = text_num + 1;

      }

      if (i%6 == 1 ) {
        fprintf ( fileout,  "texture { RedText } }\n" );
      }
      else if ( i%2 == 0 ) {
        fprintf ( fileout,  "texture { BlueText } }\n" );
      }
      else {
        fprintf ( fileout,  "texture { GreenText } }\n" );
      }
      text_num = text_num + 1;

    }

  }

  fprintf ( fileout,  "}\n" );
  text_num = text_num + 1;
/*
  Report.
*/
  printf ( "\n" );
  printf ( "POV_WRITE - Wrote %d text lines.\n", text_num );

  return SUCCESS;
}
/******************************************************************************/

int rcol_find ( float a[][COR3_MAX], int m, int n, float r[] ) 

/******************************************************************************/

/*
  Purpose:
   
    RCOL_FIND finds if a vector occurs in a table.

  Comment:

    Explicitly forcing the second dimension to be COR3_MAX is a kludge.
    I have to figure out how to do this as pointer references.

    Also, since the array is not sorted, this routine should not be carelessly
    called repeatedly for really big values of N, because you'll waste a
    lot of time.

  Modified:

    27 April 1999

  Author:
 
    John Burkardt
*/
{
  int i;
  int icol;
  int j;

  icol = -1;

  for ( j = 0; j < n; j++ ) {
    for ( i = 0; i < m; i++ ) {
      if ( a[i][j] != r[i] ) {
        break;
      }
      if ( i == m-1 ) {
        return j;
      }
    }
  }

  return icol;
}
/**********************************************************************/

float rgb_to_hue ( float r, float g, float b )

/**********************************************************************/

/*
  Purpose:

    RGB_TO_HUE converts (R,G,B) colors to a hue value between 0 and 1.

  Discussion:

    The hue computed here should be the same as the H value computed
    for HLS and HSV, except that it ranges from 0 to 1 instead of
    0 to 360.

    A monochromatic color ( white, black, or a shade of gray) does not
    have a hue.  This routine will return a special value of H = -1
    for such cases.

  Examples:

    Color    R    G    B     H

    red  1.0  0.0  0.0   0.00
    yellow   1.0  1.0  0.0   0.16
    green    0.0  1.0  0.0   0.33
    cyan     0.0  1.0  1.0   0.50
    blue     0.0  0.0  1.0   0.67
    magenta  1.0  0.0  1.0   0.83

    black    0.0  0.0  0.0  -1.00
    gray     0.5  0.5  0.5  -1.00
    white    1.0  1.0  1.0  -1.00

  Modified:

    22 May 1999

  Author:

    John Burkardt

  Parameters:

    Input, float R, G, B, the red, green and blue values of the color.
    These values should be between 0 and 1.

    Output, float RGB_TO_HUE, the corresponding hue of the color, or -1.0 if
    the color is monochromatic.
*/
{
  float h;
  float rgbmax;
  float rgbmin;
/*
  Make sure the colors are between 0 and 1.
*/
  if ( r < 0.0 ) {
    r = 0.0;
  }
  else if ( r > 1.0 ) {
    r = 1.0;
  }

  if ( g < 0.0 ) {
    g = 0.0;
  }
  else if ( g > 1.0 ) {
    g = 1.0;
  }

  if ( b < 0.0 ) {
    b = 0.0;
  }
  else if ( b > 1.0 ) {
    b = 1.0;
  }
/*
  Compute the minimum and maximum of R, G and B.
*/
  rgbmax = r;
  if ( g > rgbmax ) {
    rgbmax = g;
  }
  if ( b > rgbmax ) {
    rgbmax = b;
  }

  rgbmin = r;
  if ( g < rgbmin ) {
    rgbmin = g;
  }
  if ( b < rgbmin ) {
    rgbmin = b;
  }
/*
  If RGBMAX = RGBMIN, { the color has no hue.
*/
  if ( rgbmax == rgbmin ) {
    h = - 1.0;
  }
/*
  Otherwise, we need to determine the dominant color.
*/
  else {

    if ( r == rgbmax ) {
      h = ( g - b ) / ( rgbmax - rgbmin );
    }
    else if ( g == rgbmax ) {
      h = 2.0 + ( b - r ) / ( rgbmax - rgbmin );
    }
    else if ( b == rgbmax ) {
      h = 4.0 + ( r - g ) / ( rgbmax - rgbmin );
    }

    h = h / 6.0;
/*
  Make sure H lies between 0 and 1.0.
*/
    if ( h < 0.0 ) {
      h = h + 1.0;
    }
    else if ( h > 1.0 ) {
      h = h - 1.0;
    }

  }

  return h;
}
/******************************************************************************/

short int short_int_read ( FILE *filein )

/******************************************************************************/
/*
  Purpose:

    SHORT_INT_READ reads a short int from a binary file.

  Modified:

    14 October 1998

  Author:

    John Burkardt
*/
{
  unsigned char  c1;
  unsigned char  c2;
  short int      ival;

  c1 = fgetc ( filein );
  c2 = fgetc ( filein );

  ival = c1 | ( c2 << 8 );

  return ival;
}
/******************************************************************************/

int short_int_write ( FILE *fileout, short int short_int_val )

/******************************************************************************/

/*
  Purpose:

    SHORT_INT_WRITE writes a short int to a binary file.

  Modified:

    14 October 1998

  Author:

    John Burkardt
*/
{
  union {
    short int yint;
    char ychar[2];
  } y;

  y.yint = short_int_val;

  if ( byte_swap == TRUE ) {
    fputc ( y.ychar[1], fileout );
    fputc ( y.ychar[0], fileout );
  }
  else {
    fputc ( y.ychar[0], fileout );
    fputc ( y.ychar[1], fileout );
  }

  return 2;
}
/******************************************************************************/

int smf_read ( FILE *filein )

/******************************************************************************/

/*
  Purpose:
   
    SMF_READ reads an SMF file.

  Example:

    #SMF2.0
    #  cube_face.smf
    #  This example demonstrates how an RGB color can be assigned to
    #  each face of an object.
    #    
    # First, define the geometry of the cube.
    #
    v 0.0  0.0  0.0
    v 1.0  0.0  0.0
    v 0.0  1.0  0.0
    v 1.0  1.0  0.0
    v 0.0  0.0  1.0
    v 1.0  0.0  1.0
    v 0.0  1.0  1.0
    v 1.0  1.0  1.0
    f 1 4 2
    f 1 3 4
    f 5 6 8
    f 5 8 7
    f 1 2 6
    f 1 6 5
    f 2 4 8
    f 2 8 6
    f 4 3 7
    f 4 7 8
    f 3 1 5
    f 3 5 7
    #
    #  Colors will be bound 1 per face.
    #
    bind c face
    c 1.0  0.0  0.0
    c 1.0  0.0  0.0
    c 0.0  1.0  0.0
    c 0.0  1.0  0.0
    c 0.0  0.0  1.0
    c 0.0  0.0  1.0
    c 1.0  1.0  0.0
    c 1.0  1.0  0.0
    c 0.0  1.0  1.0
    c 0.0  1.0  1.0
    c 1.0  0.0  1.0
    c 1.0  0.0  1.0
    #
    #  Normal vectors will be bound 1 per face.
    #
    bind n face
    n  0.0   0.0  -1.0
    n  0.0   0.0  -1.0
    n  0.0   0.0   1.0
    n  0.0   0.0   1.0
    n  0.0  -1.0   0.0
    n  0.0  -1.0   0.0
    n  1.0   0.0   0.0
    n  1.0   0.0   0.0
    n  0.0   1.0   0.0
    n  0.0   1.0   0.0
    n -1.0   0.0   0.0
    n -1.0   0.0   0.0
    #
    #  Texture coordinate pairs will be bound 1 per face.
    #
    bind r face
    r  0.0   0.0
    r  0.0   0.1
    r  0.0   0.2
    r  0.0   0.3
    r  0.1   0.0
    r  0.1   0.1
    r  0.1   0.2
    r  0.1   0.3
    r  0.2   0.0
    r  0.2   0.1
    r  0.2   0.2
    r  0.2   0.3

  Modified:

    03 July 1999

  Author:
 
    John Burkardt
*/
{
  float angle;
  char  axis;
  float b;
  char  cnr[LINE_MAX_LEN];
  int   count;
  float dx;
  float dy;
  int   face_count;
  float g;
  int   icor3_normal;
  int   icor3_tex_uv;
  int   iface_normal;
  int   iface_tex_uv;
  int   imat;
  int   ivert;
  int   level;
  char *next;
  int   node;
  int   node_count;
  float r;
  float r1;
  float r2;
  float r3;
  float rgba[4];
  char *string;
  float sx;
  float sy;
  float sz;
  char  token[LINE_MAX_LEN];
  char  token2[LINE_MAX_LEN];
  char  type[LINE_MAX_LEN];
  float u;
  float v;
  int   vertex_base;
  int   vertex_correction;
  int   width;
  float x;
  float xvec[3];
  float y;
  float z;

  face_count = 0;
  icor3_normal = 0;
  icor3_tex_uv = 0;
  iface_normal = 0;
  iface_tex_uv = 0;
  level = 0;
  node_count = 0;
  vertex_base = 0;
  vertex_correction = 0;
/* 
  Read the next line of the file into INPUT. 
*/
  while ( fgets ( input, LINE_MAX_LEN, filein ) != NULL ) {

    text_num = text_num + 1;

    if ( debug ) {
      printf ( "SMF_READ: DEBUG: Reading line #%d\n", text_num );
    }
/* 
  Advance to the first nonspace character in INPUT. 
*/
    for ( next = input; *next != '\0' && isspace(*next); next++ ) {
    }
/* 
  Skip blank lines. 
*/

    if ( *next == '\0' ) {
      continue;
    }
/*
  Skip comment lines.
*/
    if ( *next == '#' || *next == '$' ) {
      comment_num = comment_num + 1;
      continue;
    }
/* 
  Extract the first word in this line. 
*/
    sscanf ( next, "%s%n", token, &width );
/* 
  Set NEXT to point to just after this token. 
*/
    next = next + width;
/*
  BEGIN
  Reset the transformation matrix to identity.
  Node numbering starts at zero again.  (Really, this is level based)
  (Really should define a new transformation matrix, and concatenate.)
  (Also, might need to keep track of level.)
*/
    if ( leqi ( token, "BEGIN" ) == TRUE ) {

      level = level + 1;

      vertex_base = cor3_num;
      group_num = group_num + 1;
      tmat_init ( transform_matrix );

    }
/*
  BIND [c|n|r] [vertex|face]
  Specify the binding for RGB color, Normal, or Texture.
  Options are "vertex" or "face"
*/
    else if ( leqi ( token, "BIND" ) == TRUE ) {

      sscanf ( next, "%s%n", cnr, &width );
      next = next + width;

      if ( debug ) {
        printf ( "CNR = %s\n", cnr );
      }

      sscanf ( next, "%s%n", type, &width );
      next = next + width;

      if ( debug ) {
        printf ( "TYPE = %s\n", type );
      }

      if ( leqi ( cnr, "C" ) == TRUE ) {

        if ( leqi ( type, "VERTEX" ) == TRUE ) {
          strcpy ( material_binding, "PER_VERTEX" );
        }
        else if ( leqi ( type, "FACE" ) == TRUE ) {
          strcpy ( material_binding, "PER_FACE" );
        }

      }
      else if ( leqi ( cnr, "N" ) == TRUE ) {

        if ( leqi ( type, "VERTEX" ) == TRUE ) {
          strcpy ( normal_binding, "PER_VERTEX" );
        }
        else if ( leqi ( type, "FACE" ) == TRUE ) {
          strcpy ( normal_binding, "PER_FACE" );
        }

      }
      else if ( leqi ( cnr, "R" ) == TRUE ) {

        if ( leqi ( type, "VERTEX" ) == TRUE ) {
          strcpy ( texture_binding, "PER_VERTEX" );
        }
        else if ( leqi ( type, "FACE" ) == TRUE ) {
          strcpy ( texture_binding, "PER_FACE" );
        }

      }

    }
/*
  C <r> <g> <b>
  Specify an RGB color, with R, G, B between 0.0 and 1.0.
*/
    else if ( leqi ( token, "C" ) == TRUE ) {

      sscanf ( next, "%f%n", &r, &width );
      next = next + width;

      sscanf ( next, "%f%n", &g, &width );
      next = next + width;

      sscanf ( next, "%f%n", &b, &width );
      next = next + width;
/*
    Set up a temporary material (R,G,B,1.0).
    Add the material to the material database, or find the index of
      a matching material already in.
    Assign the material of the node or face to this index.
*/
      rgba[0] = r;
      rgba[1] = g;
      rgba[2] = b;
      rgba[3] = 1.0;

      if ( material_num < MATERIAL_MAX ) {

        for ( k = 0; k < 4; k++ ) {
          material_rgba[k][material_num] = rgba[k];
        }

        imat = material_num;
        material_num = material_num + 1;

      }
      else {

        imat = 0;

      }

      if ( leqi ( material_binding, "PER_FACE" ) == TRUE ) {

        face_count = face_count + 1;
        face_material[face_count] = imat;

      }
      else if ( leqi ( material_binding, "PER_VERTEX" ) == TRUE ) {

        node_count = node_count + 1;
        cor3_material[node_count] = imat;

      }
      else {

        printf ( "\n" );
        printf ( "SMF_READ - Fatal error!\n" );
        printf ( "  Material binding undefined!\n" );
        return ERROR;

      }

    }
/*
  END
  Drop down a level. 
*/
    else if ( leqi ( token, "END" ) == TRUE ) {

      level = level - 1;

      if ( level < 0 ) {
        printf ( "\n" );
        printf ( "SMF_READ - Fatal error!\n" );
        printf ( "  More END statements than BEGINs!\n" );
        return ERROR;
      }
    }
/*  
  F V1 V2 V3

  Face.
  A face is defined by the vertices.
  Node indices are 1 based rather than 0 based.
  So we have to decrement them before loading them into FACE.
  Note that vertex indices start back at 0 each time a BEGIN is entered.
  The strategy here won't handle nested BEGIN's, just one at a time.
*/

    else if ( leqi ( token, "F" ) == TRUE ) {

      ivert = 0;
      face_order[face_num] = 0;
/*
  Read each item in the F definition as a token, and then
  take it apart.
*/
      for ( ;; ) {

        count = sscanf ( next, "%s%n", token2, &width );
        next = next + width;
 
        if ( count != 1 ) {
          break;
        }
 
        count = sscanf ( token2, "%d%n", &node, &width );

        if ( count != 1 ) {
          break;
        }

        if ( ivert < ORDER_MAX && face_num < FACE_MAX ) {
          face[ivert][face_num] = node - 1 + vertex_base;
          vertex_material[ivert][face_num] = 0;
          face_order[face_num] = face_order[face_num] + 1;
        } 
        ivert = ivert + 1;
      } 
      face_num = face_num + 1;
    }
/*
  N <x> <y> <z>
  Specify a normal vector.
*/
    else if ( leqi ( token, "N" ) == TRUE ) {

      sscanf ( next, "%f%n", &x, &width );
      next = next + width;

      sscanf ( next, "%f%n", &y, &width );
      next = next + width;

      sscanf ( next, "%f%n", &z, &width );
      next = next + width;

      if ( leqi ( normal_binding, "PER_FACE" ) == TRUE ) {

        face_normal[0][iface_normal] = x;
        face_normal[1][iface_normal] = y;
        face_normal[2][iface_normal] = z;

        iface_normal = iface_normal + 1;

      }
      else if ( leqi ( normal_binding, "PER_VERTEX" ) == TRUE ) {

        cor3_normal[0][icor3_normal] = x;
        cor3_normal[1][icor3_normal] = y;
        cor3_normal[2][icor3_normal] = z;

        icor3_normal = icor3_normal + 1;

      }
      else {

        printf ( "\n" );
        printf ( "SMF_READ - Fatal error!\n" );
        printf ( "  Normal binding undefined!\n" );
        return ERROR;
                    
      }
    }
/*
  R <u> <v>
  Specify a texture coordinate.
*/
    else if ( leqi ( token, "R" ) == TRUE ) {

      sscanf ( next, "%f%n", &u, &width );
      next = next + width;

      sscanf ( next, "%f%n", &v, &width );
      next = next + width;

      if ( leqi ( texture_binding, "PER_FACE" ) == TRUE ) {

        face_tex_uv[0][iface_tex_uv] = u;
        face_tex_uv[1][iface_tex_uv] = v;

        icor3_tex_uv = icor3_tex_uv + 1;

      }
      else if ( leqi ( texture_binding, "PER_VERTEX" ) == TRUE ) {

        cor3_tex_uv[0][icor3_tex_uv] = u;
        cor3_tex_uv[1][icor3_tex_uv] = v;

        icor3_tex_uv = icor3_tex_uv + 1;
      }
      else {
        printf ( "\n" );
        printf ( "SMF_READ - Fatal error!\n" );
        printf ( "  Texture binding undefined!\n" );
        return ERROR;
      }

    }
/*
  ROT [x|y|z] <theta>
*/
    else if ( leqi ( token, "ROT" ) == TRUE ) {

      sscanf ( next, "%c%n", &axis, &width );
      next = next + width;

      sscanf ( next, "%f%n", &angle, &width );
      next = next + width;

      tmat_rot_axis ( transform_matrix, transform_matrix, angle, axis );

    }
/*
  SCALE <sx> <sy> <sz>
*/
    else if ( leqi ( token, "SCALE" ) == TRUE ) {

      sscanf ( next, "%f%n", &sx, &width );
      next = next + width;

      sscanf ( next, "%f%n", &sy, &width );
      next = next + width;

      sscanf ( next, "%f%n", &sz, &width );
      next = next + width;

      tmat_scale ( transform_matrix, transform_matrix, sx, sy, sz );
    }
/*
  SET VERTEX_CORRECTION <i>
  Specify increment to add to vertex indices in file.
*/
    else if ( leqi ( token, "SET" ) == TRUE ) {

      sscanf ( next, "%s%n", cnr, &width );
      next = next + width;

      sscanf ( next, "%d%n", &vertex_correction, &width );
      next = next + width;

    }
/*
  T_SCALE <dx> <dy>
  Specify a scaling to texture coordinates.
*/
    else if ( leqi ( token, "T_SCALE" ) == TRUE ) {

      sscanf ( next, "%f%n", &dx, &width );
      next = next + width;

      sscanf ( next, "%f%n", &dy, &width );
      next = next + width;

    }
/*
  T_TRANS <dx> <dy>
  Specify a translation to texture coordinates.
*/
    else if ( leqi ( token, "T_TRANS" ) == TRUE ) {

      sscanf ( next, "%f%n", &dx, &width );
      next = next + width;

      sscanf ( next, "%f%n", &dy, &width );
      next = next + width;

    }
/*
  TEX <filename>
  Specify a filename containing the texture.
  (ANY CHANCE THIS IS RIGHT?)
*/
    else if ( leqi ( token, "TEX" ) == TRUE ) {

      sscanf ( next, "%s%n", string, &width );

      for ( i = 0; i < LINE_MAX_LEN; i++ ) {
        texture_name[texture_num][i] = string[i];
        if ( string[i] == '\0' ) {
          break;
        }
      }

      texture_num = texture_num + 1;

    }
/*
  TRANS <dx> <dy> <dz>
*/
    else if ( leqi ( token, "TRANS" ) == TRUE ) {

      sscanf ( next, "%f%n", &x, &width );
      next = next + width;

      sscanf ( next, "%f%n", &y, &width );
      next = next + width;

      sscanf ( next, "%f%n", &z, &width );
      next = next + width;

      tmat_trans ( transform_matrix, transform_matrix, x, y, z );
    }
/*
  V X Y Z
  Geometric vertex.
*/
    else if ( leqi ( token, "V" ) == TRUE ) {

      sscanf ( next, "%e %e %e", &r1, &r2, &r3 );

      xvec[0] = r1;
      xvec[1] = r2;
      xvec[2] = r3;
/*
  Apply current transformation matrix.
  Right now, we can only handle one matrix, not a stack of
  matrices representing nested BEGIN/END's.
*/
      tmat_mxp ( transform_matrix, xvec, xvec );

      if ( cor3_num < COR3_MAX ) {
        for ( i = 0; i < 3; i++ ) {
          cor3[i][cor3_num] = xvec[i];
        }
      }

      cor3_num = cor3_num + 1;

    }
/*
  Unrecognized keyword.
*/
    else {

      bad_num = bad_num + 1;

      if ( bad_num <= 10 ) {
        printf ( "\n" );
        printf ( "SMF_READ: Bad data on line %d.\n", text_num );
      }
    }

  }
/*
  Extend the material definition 
  * from the face to the vertices and nodes, or
  * from the vertices to the faces and nodes.
*/
  if ( strcmp ( material_binding, "PER_FACE" ) == 0 ) {

    face_to_vertex_material ( );

    vertex_to_node_material ( );

  }
  else if ( strcmp ( material_binding, "PER_VERTEX" ) == 0 ) {

    node_to_vertex_material ( );

    vertex_to_face_material ( );

  }

  return SUCCESS;
}
/******************************************************************************/

int smf_write ( FILE *fileout )

/******************************************************************************/

/*
  Purpose:
   
    SMF_WRITE writes graphics information to an SMF file.

  Example:

    #SMF2.0
    #  cube_face.smf
    #  This example demonstrates how an RGB color can be assigned to
    #  each face of an object.
    #    
    # First, define the geometry of the cube.
    #
    v 0.0  0.0  0.0
    v 1.0  0.0  0.0
    v 0.0  1.0  0.0
    v 1.0  1.0  0.0
    v 0.0  0.0  1.0
    v 1.0  0.0  1.0
    v 0.0  1.0  1.0
    v 1.0  1.0  1.0
    f 1 4 2
    f 1 3 4
    f 5 6 8
    f 5 8 7
    f 1 2 6
    f 1 6 5
    f 2 4 8
    f 2 8 6
    f 4 3 7
    f 4 7 8
    f 3 1 5
    f 3 5 7
    #
    #  Colors will be bound 1 per face.
    #
    bind c face
    c 1.0  0.0  0.0
    c 1.0  0.0  0.0
    c 0.0  1.0  0.0
    c 0.0  1.0  0.0
    c 0.0  0.0  1.0
    c 0.0  0.0  1.0
    c 1.0  1.0  0.0
    c 1.0  1.0  0.0
    c 0.0  1.0  1.0
    c 0.0  1.0  1.0
    c 1.0  0.0  1.0
    c 1.0  0.0  1.0
    #
    #  Normal vectors will be bound 1 per face.
    #
    bind n face
    n  0.0   0.0  -1.0
    n  0.0   0.0  -1.0
    n  0.0   0.0   1.0
    n  0.0   0.0   1.0
    n  0.0  -1.0   0.0
    n  0.0  -1.0   0.0
    n  1.0   0.0   0.0
    n  1.0   0.0   0.0
    n  0.0   1.0   0.0
    n  0.0   1.0   0.0
    n -1.0   0.0   0.0
    n -1.0   0.0   0.0
    #
    #  Texture coordinate pairs will be bound 1 per face.
    #
    bind r face
    r  0.0   0.0
    r  0.0   0.1
    r  0.0   0.2
    r  0.0   0.3
    r  0.1   0.0
    r  0.1   0.1
    r  0.1   0.2
    r  0.1   0.3
    r  0.2   0.0
    r  0.2   0.1
    r  0.2   0.2
    r  0.2   0.3

  Modified:

    05 July 1999

  Author:
 
    John Burkardt
*/
{
  int   i;
  int   icor3;
  int   iface;
  int   imat;
  int   ivert;
  int   text_num;
/* 
  Initialize. 
*/
  text_num = 0;

  fprintf ( fileout, "#$SMF 2.0\n" );
  fprintf ( fileout, "#$vertices %d\n", cor3_num );
  fprintf ( fileout, "#$faces %d\n", face_num );
  fprintf ( fileout, "#\n" );
  fprintf ( fileout, "# %s created by IVCON.\n", fileout_name );
  fprintf ( fileout, "# Original data in %s.\n", filein_name );
  fprintf ( fileout, "#\n" );

  text_num = text_num + 7;
/* 
  V: vertex coordinates. 
*/
  for ( i = 0; i < cor3_num; i++ ) {
    fprintf ( fileout, "v %f %f %f\n", 
      cor3[0][i], cor3[1][i], cor3[2][i] );
    text_num = text_num + 1;
  }
/* 
  F: faces. 
*/
  if ( face_num > 0 ) {
    fprintf ( fileout, "\n" );
    text_num = text_num + 1;
  }

  for ( iface = 0; iface < face_num; iface++ ) {

    fprintf ( fileout, "f" );
    for ( ivert = 0; ivert < face_order[iface]; ivert++ ) {
      fprintf ( fileout, " %d", face[ivert][iface]+1 );
    }
    fprintf ( fileout, "\n" );
    text_num = text_num + 1;
  }
/*
  Material binding.
*/
  fprintf ( fileout, "bind c vertex\n" );
  text_num = text_num + 1;
/*
  Material RGB values at each node.
*/
  for ( icor3 = 0; icor3 < cor3_num; icor3++ ) {

    imat = cor3_material[icor3];

    fprintf ( fileout, "c %f %f %f\n", material_rgba[0][imat], 
      material_rgba[1][imat], material_rgba[2][imat] );

    text_num = text_num + 1;
  }
/*
  Normal binding.
*/
  fprintf ( fileout, "bind n vertex\n" );
  text_num = text_num + 1;
/*
  Normal vector at each node.
*/
  for ( icor3 = 0; icor3 < cor3_num; icor3++ ) {

    fprintf ( fileout, "n %f %f %f\n", cor3_normal[0][icor3],
      cor3_normal[1][icor3], cor3_normal[2][icor3] );

    text_num = text_num + 1;
  }

  if ( texture_num > 0 ) {
/*
  Texture filename.
*/
    fprintf ( fileout, "tex %s\n", texture_name[0] );
    text_num = text_num + 1;
/*
  Texture binding.
*/
    fprintf ( fileout, "bind r vertex\n" );
    text_num = text_num + 1;
/*
  Texture coordinates at each node.
*/
    for ( icor3 = 0; icor3 < cor3_num; icor3++ ) {
      fprintf ( fileout, "r %f %f\n", cor3_tex_uv[0][icor3], 
        cor3_tex_uv[1][icor3] );
      text_num = text_num + 1;
    }

  }
/*
  Report.
*/
  printf ( "\n" );
  printf ( "SMF_WRITE - Wrote %d text lines.\n", text_num );

  return SUCCESS;
}
/******************************************************************************/

int stla_read ( FILE *filein )

/******************************************************************************/

/*
  Purpose:
   
    STLA_READ reads an ASCII STL (stereolithography) file.

  Examples:

    solid MYSOLID
      facet normal 0.4 0.4 0.2
        outerloop
          vertex  1.0 2.1 3.2
          vertex  2.1 3.7 4.5
          vertex  3.1 4.5 6.7
        endloop
      endfacet
      ...
      facet normal 0.2 0.2 0.4
        outerloop
          vertex  2.0 2.3 3.4
          vertex  3.1 3.2 6.5
          vertex  4.1 5.5 9.0
        endloop
      endfacet
    endsolid MYSOLID

  Modified:

    20 October 1998

  Author:
 
    John Burkardt
*/
{
  int   count;
  int   i;
  int   icor3;
  int   ivert;
  char *next;
  float r1;
  float r2;
  float r3;
  float r4;
  float temp[3];
  char  token[LINE_MAX_LEN];
  int   width;
/*
  Read the next line of the file into INPUT. 
*/
  while ( fgets ( input, LINE_MAX_LEN, filein ) != NULL ) {

    text_num = text_num + 1;
/*
  Advance to the first nonspace character in INPUT. 
*/
    for ( next = input; *next != '\0' && isspace(*next); next++ ) {
    }
/*
  Skip blank lines and comments. 
*/
    if ( *next == '\0' || *next == '#' || *next == '!' || *next == '$' ) {
      continue;
    }
/*
  Extract the first word in this line. 
*/
    sscanf ( next, "%s%n", token, &width );
/*
  Set NEXT to point to just after this token. 
*/
    next = next + width;
/*
  FACET
*/
    if ( leqi ( token, "facet" ) == TRUE ) {
/* 
  Get the XYZ coordinates of the normal vector to the face. 
*/
      sscanf ( next, "%*s %e %e %e", &r1, &r2, &r3 );  

      if ( face_num < FACE_MAX ) {
        face_normal[0][face_num] = r1;
        face_normal[1][face_num] = r2;
        face_normal[2][face_num] = r3;
      }

      fgets ( input, LINE_MAX_LEN, filein );
      text_num = text_num + 1;

      ivert = 0;

      for ( ;; ) {

        fgets ( input, LINE_MAX_LEN, filein );
        text_num = text_num + 1;

        count = sscanf ( input, "%*s %e %e %e", &r1, &r2, &r3 );

        if ( count != 3 ) {
          break;
        }

        temp[0] = r1;
        temp[1] = r2;
        temp[2] = r3;

        if ( cor3_num < 1000 ) {
          icor3 = rcol_find ( cor3, 3, cor3_num, temp );
        }
        else {
          icor3 = -1;
        }

        if ( icor3 == -1 ) {

          icor3 = cor3_num;

          if ( cor3_num < COR3_MAX ) {
            for ( i = 0; i < 3; i++ ) {
              cor3[i][cor3_num] = temp[i];
            }
          }
          cor3_num = cor3_num + 1;
        }
        else {
          dup_num = dup_num + 1;
        }

        if ( ivert < ORDER_MAX && face_num < FACE_MAX ) {
          face[ivert][face_num] = icor3;
          vertex_material[ivert][face_num] = 0;
          for ( i = 0; i < 3; i++ ) {
            vertex_normal[i][ivert][face_num] = face_normal[i][face_num];
          }
        }

        ivert = ivert + 1;
      } 

      fgets ( input, LINE_MAX_LEN, filein );
      text_num = text_num + 1;

      if ( face_num < FACE_MAX ) {
        face_order[face_num] = ivert;
      } 

      face_num = face_num + 1;

    }
/*
  COLOR 
*/

    else if ( leqi ( token, "color" ) == TRUE ) {
      sscanf ( next, "%*s %f %f %f %f", &r1, &r2, &r3, &r4 );
    }
/* 
 SOLID 
*/
    else if ( leqi ( token, "solid" ) == TRUE ) {
      object_num = object_num + 1;
    }
/* 
 ENDSOLID 
*/
    else if ( leqi ( token, "endsolid" ) == TRUE ) {
    }
/* 
  Unexpected or unrecognized. 
*/
    else {
      printf ( "\n" );
      printf ( "STLA_READ - Fatal error!\n" );
      printf ( "  Unrecognized first word on line.\n" );
      return ERROR;
    }

  }
  return SUCCESS;
}
/******************************************************************************/

int stla_write ( FILE *fileout )

/******************************************************************************/

/*
  Purpose:
   
    STLA_WRITE writes an ASCII STL (stereolithography) file.

  Examples:

    solid MYSOLID
      facet normal 0.4 0.4 0.2
        outerloop
          vertex  1.0 2.1 3.2
          vertex  2.1 3.7 4.5
          vertex  3.1 4.5 6.7
        endloop
      endfacet
      ...
      facet normal 0.2 0.2 0.4
        outerloop
          vertex  2.0 2.3 3.4
          vertex  3.1 3.2 6.5
          vertex  4.1 5.5 9.0
        endloop
      endfacet
    endsolid

  Discussion:

    The polygons in an STL file should only be triangular.  This routine 
    will try to automatically decompose higher-order polygonal faces into 
    suitable triangles, without actually modifying the internal graphics 
    data.

  Modified:

    01 September 1998

  Author:
 
    John Burkardt
*/
{
  int icor3;
  int iface;
  int jvert;
  int face_num2;
  int text_num;
/*
  Initialize.
*/
  text_num = 0;
  face_num2 = 0;

  fprintf ( fileout, "solid MYSOLID created by IVCON, original data in %s\n", 
    filein_name );

  text_num = text_num + 1;

  for ( iface = 0; iface < face_num; iface++ ) {

    for ( jvert = 2; jvert < face_order[iface]; jvert++ ) {

      face_num2 = face_num2 + 1;

      fprintf ( fileout, "  facet normal %f %f %f\n", 
        face_normal[0][iface], face_normal[1][iface], face_normal[2][iface] );

      fprintf ( fileout, "    outer loop\n" );

      icor3 = face[0][iface];
      fprintf ( fileout, "      vertex %f %f %f\n", 
        cor3[0][icor3], cor3[1][icor3], cor3[2][icor3] );

      icor3 = face[jvert-1][iface];
      fprintf ( fileout, "      vertex %f %f %f\n", 
        cor3[0][icor3], cor3[1][icor3], cor3[2][icor3] );

      icor3 = face[jvert][iface];
      fprintf ( fileout, "      vertex %f %f %f\n", 
        cor3[0][icor3], cor3[1][icor3], cor3[2][icor3] );

      fprintf ( fileout, "    endloop\n" );
      fprintf ( fileout, "  endfacet\n" );
      text_num = text_num + 7;
    }
  }

  fprintf ( fileout, "endsolid MYSOLID\n" );
  text_num = text_num + 1;
/*
  Report.
*/
  printf ( "\n" );
  printf ( "STLA_WRITE - Wrote %d text lines.\n", text_num );

  if ( face_num != face_num2 ) {
    printf ( "  Number of faces in original data was %d.\n", face_num );
    printf ( "  Number of triangular faces in decomposed data is %d.\n",
      face_num2 );
  }

  return SUCCESS;
}
/******************************************************************************/

int stlb_read ( FILE *filein )

/******************************************************************************/

/*
  Purpose:
   
    STLB_READ reads a binary STL (stereolithography) file.

  Example:

    80 byte string = header containing nothing in particular

    4 byte int = number of faces

    For each face:

      3 4-byte floats = components of normal vector to face;
      3 4-byte floats = coordinates of first node;
      3 4-byte floats = coordinates of second node;
      3 4-byte floats = coordinates of third and final node;
        2-byte int = attribute, whose value is 0.

  Modified:

    24 May 1999

  Author:
 
    John Burkardt
*/
{
  short int attribute = 0;
  char c;
  float cvec[3];
  int icor3;
  int i;
  int iface;
  int ivert;
/* 
  80 byte Header.
*/
  for ( i = 0; i < 80; i++ ) {
    c = char_read ( filein );
    if ( debug ) {
      printf ( "%d\n", c );
    }
    bytes_num = bytes_num + 1;
 }
/*
  Number of faces.
*/
  face_num = long_int_read ( filein );
  bytes_num = bytes_num + 4;
/*
  For each (triangular) face,
    components of normal vector,
    coordinates of three vertices,
    2 byte "attribute".
*/
  for ( iface = 0; iface < face_num; iface++ ) {

    face_order[iface] = 3;
    face_material[iface] = 0;

    for ( i = 0; i < 3; i++ ) {
      face_normal[i][iface] = float_read ( filein );
      bytes_num = bytes_num + 4;
    }

    for ( ivert = 0; ivert < face_order[iface]; ivert++ ) {

      for ( i = 0; i < 3; i++ ) {
        cvec[i] = float_read ( filein );
        bytes_num = bytes_num + 4;
      }

      if ( cor3_num < 1000 ) {
        icor3 = rcol_find ( cor3, 3, cor3_num, cvec );
      }
      else {
        icor3 = -1;
      }

      if ( icor3 == -1 ) {
        icor3 = cor3_num;
        if ( cor3_num < COR3_MAX ) {
          cor3[0][cor3_num] = cvec[0];
          cor3[1][cor3_num] = cvec[1];
          cor3[2][cor3_num] = cvec[2];
        }
        cor3_num = cor3_num + 1;
      }
      else {
        dup_num = dup_num + 1;
      }

      face[ivert][iface] = icor3;

    }
    attribute = short_int_read ( filein );
    if ( debug ) {
      printf ( "ATTRIBUTE = %d\n", attribute );
    }
    bytes_num = bytes_num + 2;
  }

  return SUCCESS;
}
/******************************************************************************/

int stlb_write ( FILE *fileout )

/******************************************************************************/

/*
  Purpose:
   
    STLB_WRITE writes a binary STL (stereolithography) file.

  Example:

    80 byte string = header containing nothing in particular

    4 byte int = number of faces

    For each face:

      3 4-byte floats = components of normal vector to face;
      3 4-byte floats = coordinates of first node;
      3 4-byte floats = coordinates of second node;
      3 4-byte floats = coordinates of third and final node;
        2-byte int = attribute, whose value is 0.

  Discussion:

    The polygons in an STL file should only be triangular.  This routine 
    will try to automatically decompose higher-order polygonal faces into 
    suitable triangles, without actually modifying the internal graphics 
    data.

  Modified:

    24 May 1999

  Author:
 
    John Burkardt
*/
{
  short int attribute = 0;
  char c;
  int i;
  int icor3;
  int iface;
  int jvert;
  int face_num2;
/* 
  80 byte Header.
*/
  for ( i = 0; i < 80; i++ ) {
    c = ' ';
    bytes_num = bytes_num + char_write ( fileout, c );
  }
/*
  Number of faces.
*/
  face_num2 = 0;
  for ( iface = 0; iface < face_num; iface++ ) {
    face_num2 = face_num2 + face_order[iface] - 2;
  }

  bytes_num = bytes_num + long_int_write ( fileout, face_num2 );
/*
  For each (triangular) face,
    components of normal vector,
    coordinates of three vertices,
    2 byte "attribute".
*/
  for ( iface = 0; iface < face_num; iface++ ) {

    for ( jvert = 2; jvert < face_order[iface]; jvert++ ) {

      for ( i = 0; i < 3; i++ ) {
        bytes_num = bytes_num + float_write ( fileout, face_normal[i][iface] );
      }

      icor3 = face[0][iface];
      for ( i = 0; i < 3; i++ ) {
        bytes_num = bytes_num + float_write ( fileout, cor3[i][icor3] );
      }

      icor3 = face[jvert-1][iface];
      for ( i = 0; i < 3; i++ ) {
        bytes_num = bytes_num + float_write ( fileout, cor3[i][icor3] );
      }

      icor3 = face[jvert][iface];
      for ( i = 0; i < 3; i++ ) {
        bytes_num = bytes_num + float_write ( fileout, cor3[i][icor3] );
      }

      bytes_num = bytes_num + short_int_write ( fileout, attribute );

    }

  }
/*
  Report.
*/
  printf ( "\n" );
  printf ( "STLB_WRITE - Wrote %d bytes.\n", bytes_num );

  if ( face_num != face_num2 ) {
    printf ( "  Number of faces in original data was %d.\n", face_num );
    printf ( "  Number of triangular faces in decomposed data is %d.\n",
      face_num2 );
  }

  return SUCCESS;
}
/******************************************************************************/

void tds_pre_process ( void )

/******************************************************************************/

/*
  Purpose:

    TDS_PRE_PROCESS divides the monolithic object into acceptably small pieces.

  Note:

    The 3DS binary format allows an unsigned short int for the number of
    points, and number of faces in an object.  This limits such quantities
    to 65535.  We have at least one interesting object with more faces
    than that.  So we need to tag faces and nodes somehow.

  Modified:

    14 October 1998

  Author:

    John Burkardt
*/
{
/*  static unsigned short int BIG = 60000; */

  return;
}
/******************************************************************************/

int tds_read ( FILE *filein )

/******************************************************************************/

/*
  Purpose:
   
    TDS_READ reads a 3D Studio MAX binary 3DS file.

  Modified:

    20 October 1998

  Author:
 
    John Burkardt
*/
{
  unsigned long int   chunk_begin;
  unsigned long int   chunk_end;
  unsigned long int   chunk_length;
  unsigned long int   chunk_length2;
  unsigned long int   position;
  unsigned short int  temp_int;
  int                 version;
  int                 views_read;
/* 
  Initialize.
*/
  views_read = 0;

  temp_int = tds_read_u_short_int ( filein );

  if ( temp_int == 0x4d4d ) {

    if ( debug ) {
      printf ( "TDS_READ: DEBUG: Read magic number %0X.\n", temp_int );
    }
/* 
  Move to 28 bytes from the beginning of the file. 
*/
    position = 28;
    fseek ( filein, ( long ) position, SEEK_SET );
    version = fgetc ( filein );

    if ( version < 3 ) {
      printf ( "\n" );
      printf ( "TDS_READ - Fatal error!\n" );
      printf ( "  This routine can only read 3DS version 3 or later.\n" );
      printf ( "  The input file is version %d.\n" ,version );
      return ERROR;
    }

    if ( debug ) {
      printf ( "TDS_READ: DEBUG: Version number is %d.\n", version );
    }
/* 
  Move to 2 bytes from the beginning of the file. 
  Set CURRENT_POINTER to the first byte of the chunk.
  Set CHUNK_LENGTH to the number of bytes in the chunk.
*/
    chunk_begin = 0;
    position = 2;
    fseek ( filein, ( long ) position, SEEK_SET );

    chunk_length = tds_read_u_long_int ( filein );
    position = 6;

    chunk_end = chunk_begin + chunk_length;

    if ( debug ) {
      printf ( "TDS_READ:\n" );
      printf ( "  Chunk begin  = %lu.\n", chunk_begin );
      printf ( "  Chunk length = %lu.\n", chunk_length );
      printf ( "  Chunk end    = %lu.\n", chunk_end );
    }

    while ( position + 2 < chunk_end ) {

      temp_int = tds_read_u_short_int ( filein );
      position = position + 2;

      if ( debug ) {
        printf ( "TDS_READ: Short int = %0X, position = %lu.\n", temp_int, position );
      }

      if ( temp_int == 0x0002 ) {
        if ( debug ) {
          printf ( "TDS_READ: Read_Initial_Section:\n" );
        }
        chunk_length2 = tds_read_u_long_int ( filein );
        position = position + 4;
        position = position - 6 + chunk_length2;
        fseek ( filein, ( long ) position, SEEK_SET );
      }
      else if ( temp_int == 0x3d3d ) {
        if ( debug ) {
          printf ( "TDS_READ: Read_Edit_Section:\n" );
        }
        position = position - 2;
        position = position + tds_read_edit_section ( filein, &views_read );
      }
      else if ( temp_int == 0xb000 ) {
        if ( debug ) {
          printf ( "TDS_READ: Read_Keyframe_Section:\n" );
        }

        position = position - 2;
        position = position + tds_read_keyframe_section ( filein, &views_read );
      }
      else {
        printf ( "\n" );
        printf ( "TDS_READ - Fatal error!\n" );
        printf ( "  Unexpected input, position = %lu.\n", position );
        printf ( "  TEMP_INT = %hux\n", temp_int );
        return ERROR;
      }
    }
    position = chunk_begin + chunk_length;
    fseek ( filein, ( long ) position, SEEK_SET );
  }
  else {
    printf ( "\n" );
    printf ( "TDS_READ - Fatal error!\n" );
    printf ( "  Could not find the main section tag.\n" );
    return ERROR;
  }

  return SUCCESS;
}
/******************************************************************************/

unsigned long tds_read_ambient_section ( FILE *filein )

/******************************************************************************/

{
  unsigned long int   current_pointer;
  unsigned char       end_found = FALSE;
  int                 i;
  long int            pointer;
  float               rgb_val[3];
  unsigned short int  temp_int;
  unsigned long int   temp_pointer;
  unsigned long int   teller; 
  unsigned char       true_c_val[3];
 
  current_pointer = ftell ( filein ) - 2;
  temp_pointer = tds_read_u_long_int ( filein );
  teller = 6;
 
  while ( end_found == FALSE ) {

    temp_int = tds_read_u_short_int ( filein );
    teller = teller + 2;
 
    switch ( temp_int ) {
      case 0x0010:
        if ( debug ) {
          printf ( "     COLOR_F color definition section tag of %0X\n", 
            temp_int );
        }
        for ( i = 0; i < 3; i++ ) {
          rgb_val[i] = float_read ( filein );
        }
        if ( debug ) {
          printf ( "RGB_VAL = %f %f %f\n", rgb_val[0], rgb_val[1], rgb_val[2] );
        }
        teller = teller + 3 * sizeof ( float );
        break;
      case 0x0011:
        if ( debug ) {
          printf ( "     COLOR_24 24 bit color definition section tag of %0X\n",
            temp_int );
        }

        for ( i = 0; i < 3; i++ ) {
          true_c_val[i] = fgetc ( filein );
        }
        if ( debug ) {
          printf ( "TRUE_C_VAL = %d %d %d\n", true_c_val[0], true_c_val[1], 
            true_c_val[2] );
        }
        teller = teller + 3;
        break;
      default:
        break;
    }
 
    if ( teller >= temp_pointer ) {
      end_found = TRUE;
    }

  }
 
  pointer = ( long ) ( current_pointer + temp_pointer );
  fseek ( filein, pointer, SEEK_SET );

  return ( temp_pointer );
}
/******************************************************************************/

unsigned long tds_read_background_section ( FILE *filein )

/******************************************************************************/

{
  unsigned long int   current_pointer;
  unsigned char       end_found = FALSE;
  int                 i;
  long int            pointer;
  float               rgb_val[3];
  unsigned short int  temp_int;
  unsigned long int   temp_pointer;
  unsigned long int   teller; 
  unsigned char       true_c_val[3];
 
  current_pointer = ftell ( filein ) - 2;
  temp_pointer = tds_read_u_long_int ( filein );
  teller = 6;

  while ( end_found == FALSE ) {

    temp_int = tds_read_u_short_int ( filein );
    teller = teller + 2;
 
    switch ( temp_int ) {
      case 0x0010:
        if ( debug ) {
          printf ( "   COLOR_F RGB color definition section tag of %0X\n", 
            temp_int );
        }
        for ( i = 0; i < 3; i++ ) {
          rgb_val[i] = float_read ( filein );
        }
        if ( debug ) {
          printf ( "RGB_VAL = %f %f %f\n", rgb_val[0], rgb_val[1], rgb_val[2] );
        }
        teller = teller + 3 * sizeof ( float );
        break;
      case 0x0011:
        if ( debug ) {
          printf ( "   COLOR_24 24 bit color definition section tag of %0X\n", 
            temp_int );
        }
 
        for ( i = 0; i < 3; i++ ) {
          true_c_val[i] = fgetc ( filein );
        }
        if ( debug ) {
          printf ( "TRUE_C_VAL = %d %d %d\n", true_c_val[0], true_c_val[1], 
            true_c_val[2] );
        }
        teller = teller + 3;
        break;
      default:
        break;
    }

    if ( teller >= temp_pointer ) {
      end_found = TRUE;
    }

  }
 
  pointer = ( long ) ( current_pointer + temp_pointer );
  fseek ( filein, pointer, SEEK_SET );

  return ( temp_pointer );
}
/******************************************************************************/

unsigned long tds_read_boolean ( unsigned char *boolean, FILE *filein )

/******************************************************************************/

{
  unsigned long current_pointer;
  long int      pointer;
  unsigned long temp_pointer;
 
  current_pointer = ftell ( filein ) - 2;
  temp_pointer = tds_read_u_long_int ( filein );
 
  *boolean = fgetc ( filein );
 
  pointer = ( long ) ( current_pointer + temp_pointer );
  fseek ( filein, pointer, SEEK_SET );

  return ( temp_pointer );
}
/******************************************************************************/

unsigned long tds_read_camera_section ( FILE *filein )

/******************************************************************************/
{
  float               camera_eye[3];
  float               camera_focus[3];
  unsigned long int   current_pointer;
  float               lens;
  long int            pointer;
  float               rotation;
  unsigned long int   temp_pointer;
  unsigned short int  u_short_int_val;
 
  current_pointer = ftell ( filein ) - 2;
  temp_pointer = tds_read_u_long_int ( filein );
 
  camera_eye[0] = float_read ( filein );
  camera_eye[1] = float_read ( filein );
  camera_eye[2] = float_read ( filein );
 
  camera_focus[0] = float_read ( filein );
  camera_focus[1] = float_read ( filein );
  camera_focus[2] = float_read ( filein );

  rotation = float_read ( filein );
  lens = float_read ( filein );

  if ( debug ) {
    printf ( " Found camera viewpoint at XYZ = %f %f %f.\n",
      camera_eye[0], camera_eye[1], camera_eye[2] );
    printf ( "     Found camera focus coordinates at XYZ = %f %f %f.\n",
      camera_focus[0], camera_focus[1], camera_focus[2] );
    printf ( "     Rotation of camera is:  %f.\n", rotation );
    printf ( "     Lens in used camera is: %f mm.\n", lens );
  }
 
  if ( ( temp_pointer-38 ) > 0 ) {

    if ( debug ) {
      printf ( "          Found extra camera sections.\n" );
    }

    u_short_int_val = tds_read_u_short_int ( filein );

    if ( u_short_int_val == 0x4710 ) {
      if ( debug ) {
        printf ( "          CAM_SEE_CONE.\n" );
      }
      tds_read_unknown_section ( filein );
    }

    u_short_int_val = tds_read_u_short_int ( filein );

    if ( u_short_int_val == 0x4720 ) {
      if ( debug ) {
        printf ( "          CAM_RANGES.\n" );
      }
      tds_read_unknown_section ( filein );
    }

  }
 
  pointer = ( long ) ( current_pointer + temp_pointer );
  fseek ( filein, pointer, SEEK_SET );

  return ( temp_pointer );
}
/******************************************************************************/

unsigned long tds_read_edit_section ( FILE *filein, int *views_read )

/******************************************************************************/

/*
  Modified:

    18 September 1998
*/
{
  unsigned long int   chunk_length;
  unsigned long int   current_pointer;
  unsigned char       end_found = FALSE;
  long int            pointer;
  unsigned long int   teller;
  unsigned short int  temp_int;

  current_pointer = ftell ( filein ) - 2;
  chunk_length = tds_read_u_long_int ( filein );
  teller = 6;
 
  while ( end_found == FALSE ) {

    temp_int = tds_read_u_short_int ( filein );
    teller = teller + 2;
 
    if ( debug ) {
      printf ( "    TDS_READ_EDIT_SECTION processing tag %0X\n", temp_int );
    }

    switch ( temp_int ) {
      case 0x1100:
        if ( debug ) {
          printf ( "    BIT_MAP section tag of %0X\n", temp_int );
        }
        teller = teller + tds_read_unknown_section ( filein );
        break;
      case 0x1201:
        if ( debug ) {
          printf ( "    USE_SOLID_BGND section tag of %0X\n", temp_int );
        }
        teller = teller + tds_read_unknown_section ( filein );
        break;
      case 0x1300:
        if ( debug ) {
          printf ( "    V_GRADIENT section tag of %0X\n", temp_int );
        }
        teller = teller + tds_read_unknown_section ( filein );
        break;
      case 0x1400:
        teller = teller + tds_read_unknown_section ( filein );
        break;
      case 0x1420:
        teller = teller + tds_read_unknown_section ( filein );
        break;
      case 0x1450:
        teller = teller + tds_read_unknown_section ( filein );
        break;
      case 0x1500:
        teller = teller + tds_read_unknown_section ( filein );
        break;
      case 0x2200:
        teller = teller + tds_read_unknown_section ( filein );
        break;
      case 0x2201:
        teller = teller + tds_read_unknown_section ( filein );
        break;
      case 0x2210:
        teller = teller + tds_read_unknown_section ( filein );
        break;
      case 0x2300:
        teller = teller + tds_read_unknown_section ( filein );
        break;
      case 0x2302:
        teller = teller + tds_read_unknown_section ( filein );
        break;
      case 0x3000:
        teller = teller + tds_read_unknown_section ( filein );
        break;
      case 0x2100:
        if ( debug ) {
          printf ( "    AMBIENT_LIGHT section tag of %0X\n", temp_int );
        }
        teller = teller + tds_read_ambient_section ( filein );
        break;
      case 0x1200:
        if ( debug ) {
          printf ( "    SOLID_BGND section tag of %0X\n", temp_int );
        }
        teller = teller + tds_read_background_section ( filein );
        break;
      case 0x0100:
        if ( debug ) {
          printf ( "    MASTER_SCALE section tag of %0X\n", temp_int );
        }
        teller = teller + tds_read_unknown_section ( filein );
        break;
      case 0x3d3e:
        if ( debug ) {
          printf ( "    MESH_VERSION section tag of %0X\n", temp_int );
        }
        teller = teller + tds_read_unknown_section ( filein );
        break;
      case 0xafff:
        if ( debug ) {
          printf ( "    MAT_ENTRY section tag of %0X\n", temp_int );
        }
        teller = teller + tds_read_material_section ( filein );
        break;
      case 0x4000:
        if ( debug ) {
          printf ( "    NAMED_OBJECT section tag of %0X\n", temp_int );
        }
        teller = teller + tds_read_object_section ( filein );
        break;
      case 0x7001:
        if ( debug ) {
          printf ( "    VIEWPORT_LAYOUT section tag of %0X\n", 
            temp_int );
        }
        teller = teller + tds_read_view_section ( filein, views_read );
        break;
      case 0x7012:
        if ( debug ) {
          printf ( "    VIEWPORT_DATA_3 section tag of %0X\n", temp_int );
        }
        teller = teller + tds_read_unknown_section ( filein );
        break;
      case 0x7011:
        if ( debug ) {
          printf ( "    VIEWPORT_DATA section tag of %0X\n", temp_int );
        }
        teller = teller + tds_read_unknown_section ( filein );
        break;
      case 0x7020:
        if ( debug ) {
          printf ( "    VIEWPORT_SIZE section tag of %0X\n", temp_int );
        }
        teller = teller + tds_read_unknown_section ( filein );
        break;
      default:
        if ( debug ) {
          printf ( "    Junk.\n" );
        }
        break;
    }
 
    if ( teller >= chunk_length ) {
      end_found = TRUE;
    }

  }
 
  pointer = ( long ) ( current_pointer + chunk_length );

  fseek ( filein, pointer, SEEK_SET );

  return ( chunk_length );
}
/******************************************************************************/

unsigned long tds_read_keyframe_section ( FILE *filein, int *views_read )

/******************************************************************************/
{
  unsigned long int   current_pointer;
  unsigned char       end_found = FALSE;
  long int            pointer;
  unsigned short int  temp_int;
  unsigned long int   temp_pointer;
  unsigned long int   teller;
 
  current_pointer = ftell ( filein ) - 2;
  temp_pointer = tds_read_u_long_int ( filein );
  teller = 6;
 
  while ( end_found == FALSE ) {

    temp_int = tds_read_u_short_int ( filein );
    teller = teller + 2;

    switch ( temp_int ) {
      case 0x7001:
        if ( debug ) {
          printf ( "    VIEWPORT_LAYOUT main definition section tag of %0X\n",
            temp_int );
        }
        teller = teller + tds_read_view_section ( filein, views_read );
        break;
      case 0xb008:
        if ( debug ) {
          printf ( "    KFSEG frames section tag of %0X\n", temp_int );
        }
        teller = teller + tds_read_unknown_section ( filein );
        break;
      case 0xb002:
        if ( debug ) {
          printf ( "    OBJECT_NODE_TAG object description section tag of %0X\n",
            temp_int);
        }
        teller = teller + tds_read_keyframe_objdes_section ( filein );
        break;
      case 0xb009:
        if ( debug ) {
          printf ( "    KFCURTIME section tag of %0X\n", temp_int );
        }
        teller = teller + tds_read_unknown_section ( filein );
        break;
      case 0xb00a:
        if ( debug ) {
          printf ( "    KFHDR section tag of %0X\n", temp_int );
        }
        teller = teller + tds_read_unknown_section ( filein );
        break;
      default: 
        break;
    }
 
    if ( teller >= temp_pointer ) {
      end_found = TRUE;
    }

  }
 
  pointer = ( long ) ( current_pointer + temp_pointer );
  fseek ( filein, pointer, SEEK_SET );

  return ( temp_pointer );
}
/******************************************************************************/

unsigned long tds_read_keyframe_objdes_section ( FILE *filein )

/******************************************************************************/

/*
  Modified:

    21 September 1998
*/
{
  unsigned long int   chunk_size;
  unsigned long int   current_pointer;
  unsigned char       end_found = FALSE;
  long int            pointer;
  unsigned short int  temp_int;
  unsigned long int   temp_pointer;
  unsigned long int   teller;
  unsigned long int   u_long_int_val;
  unsigned short int  u_short_int_val;
 
  current_pointer = ftell ( filein ) - 2;
  temp_pointer = tds_read_u_long_int ( filein );
  teller = 6;
 
  while ( end_found == FALSE ) {

    temp_int = tds_read_u_short_int ( filein );
    teller = teller + 2;

    switch ( temp_int ) {
      case 0xb011:
        if ( debug ) {
          printf ( "      INSTANCE_NAME section tag of %0X\n", temp_int );
        }
        teller = teller + tds_read_unknown_section ( filein );
        break;
      case 0xb010:
        if ( debug ) {
          printf ( "      NODE_HDR section tag of %0X\n", temp_int );
        }
        teller = teller + tds_read_unknown_section ( filein );
        break;
      case 0xb020:
        if ( debug ) {
          printf ( "      POS_TRACK_TAG section tag of %0X\n", temp_int );
        }
        chunk_size = tds_read_u_long_int ( filein );
        if ( debug ) {
          printf ( "      chunk_size = %d\n", chunk_size );
        }
        u_short_int_val = tds_read_u_short_int ( filein );
        u_short_int_val = tds_read_u_short_int ( filein );
        u_short_int_val = tds_read_u_short_int ( filein );
        u_short_int_val = tds_read_u_short_int ( filein );
        u_short_int_val = tds_read_u_short_int ( filein );
        u_short_int_val = tds_read_u_short_int ( filein );
        u_short_int_val = tds_read_u_short_int ( filein );
        u_short_int_val = tds_read_u_short_int ( filein );
        u_long_int_val = tds_read_u_long_int ( filein );
        if ( debug ) {
          printf ( "u_short_int_val = %d\n", u_short_int_val );
          printf ( "u_long_int_val = %d\n", u_long_int_val );
        }
        origin[0] = float_read ( filein );
        origin[1] = float_read ( filein );
        origin[2] = float_read ( filein );
        teller = teller + 32;
        break;
      case 0xb013:
        if ( debug ) {
          printf ( "      PIVOT section tag of %0X\n", temp_int );
        }
        chunk_size = tds_read_u_long_int ( filein );
        pivot[0] = float_read ( filein );
        pivot[1] = float_read ( filein );
        pivot[2] = float_read ( filein );
        teller = teller + 12;
        break;
      case 0xb014:
        if ( debug ) {
          printf ( "      BOUNDBOX section tag of %0X\n", temp_int );
        }
        teller = teller + tds_read_unknown_section ( filein );
        break;
      case 0xb015:
        if ( debug ) {
          printf ( "      MORPH_SMOOTH section tag of %0X\n", temp_int );
        }
        teller = teller + tds_read_unknown_section ( filein );
        break;
      case 0xb021:
        if ( debug ) {
          printf ( "      ROT_TRACK_TAG section tag of %0X\n", temp_int );
        }
        teller = teller + tds_read_unknown_section ( filein );
        break;
      case 0xb022:
        if ( debug ) {
          printf ( "      SCL_TRACK_TAG section tag of %0X\n", temp_int );
        }
        teller = teller + tds_read_unknown_section ( filein );
        break;
      case 0xb030:
        if ( debug ) {
          printf ( "      NODE_ID section tag of %0X\n", temp_int );
        }
        teller = teller + tds_read_unknown_section ( filein );
        break;
      default: 
        break;
    }
 
    if ( teller >= temp_pointer ) {
      end_found = TRUE;
    }

  }
 
  pointer = ( long ) ( current_pointer+temp_pointer );
  fseek ( filein, pointer, SEEK_SET );

  return ( temp_pointer );
}
/******************************************************************************/

unsigned long tds_read_light_section ( FILE *filein )

/******************************************************************************/
{
  unsigned char       boolean;
  unsigned long int   current_pointer;
  unsigned char       end_found = FALSE;
  int                 i;
  float               light_coors[3];
  long int            pointer;
  float               rgb_val[3];
  unsigned long int   teller;
  unsigned short int  temp_int;
  unsigned long int   temp_pointer;
  unsigned char       true_c_val[3];
 
  current_pointer = ftell ( filein ) - 2;
  temp_pointer = tds_read_u_long_int ( filein );
  teller = 6;

  light_coors[0] = float_read ( filein );
  light_coors[1] = float_read ( filein );
  light_coors[2] = float_read ( filein );

  teller = teller + 3 * 4;
 
  if ( debug ) {
    printf ( "     Found light at coordinates XYZ = %f %f %f.\n",
      light_coors[0], light_coors[1], light_coors[2] );
  }
 
  while ( end_found == FALSE ) {

    temp_int = tds_read_u_short_int ( filein );
    teller = teller + 2;
 
    switch ( temp_int ) {
      case 0x0010:
        if ( debug ) {
          printf ( "      COLOR_F RGB color definition section tag of %0X\n", 
            temp_int );
        }
        for ( i = 0; i < 3; i++ ) {
          rgb_val[i] = float_read ( filein );
        }
        if ( debug ) {
          printf ( "      RGB_VAL value set to %f %f %f\n", rgb_val[0],
            rgb_val[1], rgb_val[2] );
        }
        teller = teller + 3 * sizeof ( float );
        break;
      case 0x0011:
        if ( debug ) {
          printf ( "      COLOR_24 24 bit color definition section tag of %0X\n",
            temp_int );
        }

        for ( i = 0; i < 3; i++ ) {
          true_c_val[i] = fgetc ( filein );
        }
        if ( debug ) {
          printf ( "      TRUE_C_VAL value set to %d %d %d\n", true_c_val[0],
            true_c_val[1], true_c_val[2] );
        }
        teller = teller + 3;
        break;
      case 0x4620:
        if ( debug ) {
          printf ( "      DL_OFF section: %0X\n", temp_int );
        }
        teller = teller + tds_read_boolean ( &boolean, filein );
        if ( debug ) {
          if ( boolean == TRUE ) {
            printf ( "      Light is on\n" );
          }
          else {
            printf ( "      Light is off\n" );
          }
        }
        break;
      case 0x4610:
        if ( debug  ) {
          printf ( "      DL_SPOTLIGHT section tag of %0X\n", temp_int );
        }
        teller = teller + tds_read_spot_section ( filein );
        break;
      case 0x465a:
        if ( debug  ) {
          printf ( "      DL_OUTER_RANGE section tag of %0X\n", temp_int );
        }
        teller = teller + tds_read_unknown_section ( filein );
        break;
      default:
        break;
    }
 
    if ( teller >= temp_pointer ) {
      end_found = TRUE;
    }

  }
 
  pointer = ( long ) ( current_pointer + temp_pointer );
  fseek ( filein, pointer, SEEK_SET );
 
  return ( temp_pointer );
}
/******************************************************************************/

unsigned long int tds_read_u_long_int ( FILE *filein )

/******************************************************************************/

/*
  Modified:
 
    01 October 1998

  Author:

    John Burkardt
*/
{
  union {
    unsigned long int yint;
    char ychar[4];
  } y;

  if ( byte_swap == TRUE ) {
    y.ychar[3] = fgetc ( filein );
    y.ychar[2] = fgetc ( filein );
    y.ychar[1] = fgetc ( filein );
    y.ychar[0] = fgetc ( filein );
  }
  else {
    y.ychar[0] = fgetc ( filein );
    y.ychar[1] = fgetc ( filein );
    y.ychar[2] = fgetc ( filein );
    y.ychar[3] = fgetc ( filein );
  }

  return y.yint;
}
/******************************************************************************/

int tds_read_long_name ( FILE *filein )

/******************************************************************************/
{
  unsigned char  letter;
  unsigned int   teller;

  teller = 0;
  letter = fgetc ( filein );
/*
  Could be a dummy object. 
*/
  if ( letter == 0 ) {
    strcpy ( temp_name, "Default_name" );
    return -1; 
  }

  temp_name[teller] = letter;
  teller = teller + 1;
 
  do {
    letter = fgetc ( filein );
    temp_name[teller] = letter;
    teller = teller + 1;
  } while ( letter != 0 );
 
  temp_name[teller-1] = 0;
 
  if ( debug ) {
    printf ( "      tds_read_long_name found name: %s.\n", temp_name );
  }

  return teller;
}
/******************************************************************************/

unsigned long tds_read_matdef_section ( FILE *filein )

/******************************************************************************/
{
  unsigned long int  current_pointer;
  long int           pointer;
  int                teller;
  unsigned long int  temp_pointer;
 
  current_pointer = ftell ( filein ) - 2;
  temp_pointer = tds_read_u_long_int ( filein );
 
  teller = tds_read_long_name ( filein );

  if ( teller == -1 ) {
    if ( debug ) {
      printf ( "      No material name found.\n" );
    }
  }
  else {
    strcpy ( mat_name, temp_name );
    if ( debug ) {
      printf ( "      Material name %s.\n", mat_name );
    }
  }
 
  pointer = ( long ) ( current_pointer + temp_pointer );
  fseek ( filein, pointer, SEEK_SET );

  return ( temp_pointer );
}
/******************************************************************************/

unsigned long tds_read_material_section ( FILE *filein )

/******************************************************************************/
{
  unsigned long int   current_pointer;
  unsigned char       end_found = FALSE;
  long int            pointer;
  unsigned short int  temp_int;
  unsigned long int   temp_pointer;
  unsigned long int   teller;
 
  current_pointer = ftell ( filein ) - 2;

  temp_pointer = tds_read_u_long_int ( filein );
  teller = 6;
 
  while ( end_found == FALSE ) {

    temp_int = tds_read_u_short_int ( filein );
    teller = teller + 2;
 
    switch ( temp_int ) {

      case 0xa000:
        if ( debug ) {
          printf ( "     MAT_NAME definition section tag of %0X\n", 
            temp_int );
        }
        teller = teller + tds_read_matdef_section ( filein );
        break;
      case 0xa010:
        if ( debug ) {
          printf ( "     MAT_AMBIENT definition section tag of %0X\n", 
            temp_int );
        }
        teller = teller + tds_read_unknown_section ( filein );
        break;
      case 0xa020:
        if ( debug ) {
          printf ( "     MAT_DIFFUSE definition section tag of %0X\n", 
            temp_int );
        }
        teller = teller + tds_read_unknown_section ( filein );
        break;
      case 0xa030:
        if ( debug ) {
          printf ( "     MAT_SPECULAR definition section tag of %0X\n", 
            temp_int );
        }
        teller = teller + tds_read_unknown_section ( filein );
        break;
      case 0xa040:
        if ( debug ) {
          printf ( "     MAT_SHININESS definition section tag of %0X\n", 
            temp_int );
        }
        teller = teller + tds_read_unknown_section ( filein );
        break;
      case 0xa041:
        if ( debug ) {
          printf ( "     MAT_SHIN2PCT definition section tag of %0X\n", 
            temp_int );
        }
        teller = teller + tds_read_unknown_section ( filein );
        break;
      case 0xa042:
        if ( debug ) {
          printf ( "     MAT_SHIN3PCT definition section tag of %0X\n", 
            temp_int );
        }
        teller = teller + tds_read_unknown_section ( filein );
        break;
      case 0xa050:
        if ( debug ) {
          printf ( "     MAT_TRANSPARENCY definition section tag of %0X\n", 
            temp_int );
        }
        teller = teller + tds_read_unknown_section ( filein );
        break;
      case 0xa052:
        if ( debug ) {
          printf ( "     MAT_XPFALL definition section tag of %0X\n", 
            temp_int );
        }
        teller = teller + tds_read_unknown_section ( filein );
        break;
      case 0xa053:
        if ( debug ) {
          printf ( "     MAT_REFBLUR definition section tag of %0X\n", 
            temp_int );
        }
        teller = teller + tds_read_unknown_section ( filein );
        break;
      case 0xa080:
        if ( debug ) {
          printf ( "     MAT_SELF_ILLUM definition section tag of %0X\n", 
            temp_int );
        }
        teller = teller + tds_read_unknown_section ( filein );
        break;
      case 0xa081:
        if ( debug ) {
          printf ( "     MAT_TWO_SIDE definition section tag of %0X\n", 
            temp_int );
        }
        teller = teller + tds_read_unknown_section ( filein );
        break;
      case 0xa082:
        if ( debug ) {
          printf ( "     MAT_DECAL definition section tag of %0X\n", 
            temp_int );
        }
        teller = teller + tds_read_unknown_section ( filein );
        break;
      case 0xa083:
        if ( debug ) {
          printf ( "     MAT_ADDITIVE definition section tag of %0X\n", 
            temp_int );
        }
        teller = teller + tds_read_unknown_section ( filein );
        break;
      case 0xa084:
        if ( debug ) {
          printf ( "     MAT_SELF_ILPCT definition section tag of %0X\n", 
            temp_int );
        }
        teller = teller + tds_read_unknown_section ( filein );
        break;
      case 0xa085:
        if ( debug ) {
          printf ( "     MAT_WIRE definition section tag of %0X\n", 
            temp_int );
        }
        teller = teller + tds_read_unknown_section ( filein );
        break;
      case 0xa086:
        if ( debug ) {
          printf ( "     MAT_SUPERSMP definition section tag of %0X\n", 
            temp_int );
        }
        teller = teller + tds_read_unknown_section ( filein );
        break;
      case 0xa087:
        if ( debug ) {
          printf ( "     MAT_WIRESIZE definition section tag of %0X\n", 
            temp_int );
        }
        teller = teller + tds_read_unknown_section ( filein );
        break;
      case 0xa088:
        if ( debug ) {
          printf ( "     MAT_FACEMAP definition section tag of %0X\n", 
            temp_int );
        }
        teller = teller + tds_read_unknown_section ( filein );
        break;
      case 0xa08a:
        if ( debug ) {
          printf ( "     MAT_XPFALLIN definition section tag of %0X\n", 
            temp_int );
        }
        teller = teller + tds_read_unknown_section ( filein );
        break;
      case 0xa08c:
        if ( debug ) {
          printf ( "     MAT_PHONGSOFT definition section tag of %0X\n", 
            temp_int );
        }
        teller = teller + tds_read_unknown_section ( filein );
        break;
      case 0xa08e:
        if ( debug ) {
          printf ( "     MAT_WIREABS definition section tag of %0X\n", 
            temp_int );
        }
        teller = teller + tds_read_unknown_section ( filein );
        break;
      case 0xa100:
        if ( debug ) {
          printf ( "     MAT_SHADING definition section tag of %0X\n", 
            temp_int );
        }
        teller = teller + tds_read_unknown_section ( filein );
        break;
      case 0xa200:
        if ( debug ) {
          printf ( "     MAT_TEXMAP definition section tag of %0X\n", 
            temp_int );
        }
        teller = teller + tds_read_texmap_section ( filein );
/*
        teller = teller + tds_read_unknown_section ( filein );
*/
        break;
      case 0xa204:
        if ( debug ) {
          printf ( "     MAT_SPECMAP definition section tag of %0X\n", 
            temp_int );
        }
        teller = teller + tds_read_unknown_section ( filein );
        break;
      case 0xa210:
        if ( debug ) {
          printf ( "     MAT_OPACMAP definition section tag of %0X\n", 
            temp_int );
        }
        teller = teller + tds_read_unknown_section ( filein );
        break;
      case 0xa220:
        if ( debug ) {
          printf ( "     MAT_REFLMAP definition section tag of %0X\n", 
            temp_int );
        }
        teller = teller + tds_read_unknown_section ( filein );
        break;
      case 0xa230:
        if ( debug ) {
          printf ( "     MAT_BUMPMAP definition section tag of %0X\n", 
            temp_int );
        }
        teller = teller + tds_read_unknown_section ( filein );
        break;
      case 0xa353:
        if ( debug ) {
          printf ( "     MAT_MAP_TEXBLUR definition section tag of %0X\n", 
            temp_int );
        }
        teller = teller + tds_read_unknown_section ( filein );
        break;
      default:
        if ( debug ) {
          printf ( "  Junk section tag of %0X\n", temp_int );
        }
        break;
    }
 
    if ( teller >= temp_pointer ) {
      end_found = TRUE;
    }

  }
  pointer = ( long ) ( current_pointer + temp_pointer );

  fseek ( filein, pointer, SEEK_SET );

  return ( temp_pointer );
}
/******************************************************************************/

int tds_read_name ( FILE *filein )

/******************************************************************************/
{
  unsigned char  letter;
  unsigned int   teller;

  teller = 0;
  letter = fgetc ( filein );
/*
  Could be a dummy object.  
*/

  if ( letter == 0 ) {
    strcpy ( temp_name, "Default name" );
    return (-1); 
  }

  temp_name[teller] = letter;
  teller = teller + 1;
 
  do {
    letter = fgetc ( filein );
    temp_name[teller] = letter;
    teller = teller + 1;
  } while ( ( letter != 0 ) && ( teller < 12 ) );
 
  temp_name[teller-1] = 0;
 
  if ( debug ) {
    printf ( "      tds_read_name found name: %s.\n", temp_name );
  }

  return 0;
}
/******************************************************************************/

unsigned long tds_read_obj_section ( FILE *filein )

/******************************************************************************/

/*
  Comments:

    Thanks to John F Flanagan for some suggested corrections.

  Modified:

    30 June 2001
*/
{
  unsigned short int  b;
  unsigned long int   chunk_size;
  unsigned short int  color_index;
  unsigned long int   current_pointer;
  unsigned char       end_found = FALSE;
  unsigned short int  g;
  int                 i;
  int                 j;
  int                 cor3_num_base;
  int                 cor3_num_inc;
  int                 face_num_inc;
  long int            pointer;
  unsigned short int  r;
  unsigned short int  temp_int;
  unsigned long int   temp_pointer;
  unsigned long int   temp_pointer2;
  unsigned long int   teller; 
 
  current_pointer = ftell ( filein ) - 2;
  temp_pointer = tds_read_u_long_int ( filein );
  teller = 6;
  cor3_num_base = cor3_num;

  while ( end_found == FALSE ) {

    temp_int = tds_read_u_short_int ( filein );
    teller = teller + 2;

    switch ( temp_int ) {

      case 0x4000:
        if ( debug ) {
          printf ( "        NAMED_OBJECT section tag of %0X\n", 
            temp_int );
        }
        teller = teller + tds_read_unknown_section ( filein );
        break;

      case 0x4100:
        if ( debug ) {
          printf ( "        N_TRI_OBJECT section tag of %0X\n", 
            temp_int );
        }
        teller = teller + tds_read_unknown_section ( filein );
        break;

      case 0x4110:

        if ( debug ) {
          printf ( "        POINT_ARRAY section tag of %0X\n", temp_int );
        }

        current_pointer = ftell ( filein ) - 2;
        temp_pointer2 = tds_read_u_long_int ( filein );
        cor3_num_inc =  ( int ) tds_read_u_short_int ( filein );
 
        for ( i = cor3_num; i < cor3_num + cor3_num_inc; i++ ) {
          cor3[0][i] = float_read ( filein );
          cor3[1][i] = float_read ( filein );
          cor3[2][i] = float_read ( filein );
        }
 
        cor3_num = cor3_num + cor3_num_inc;
        teller = teller + temp_pointer2;
        break;

      case 0x4111:
        if ( debug ) {
          printf ( "        POINT_FLAG_ARRAY faces (2) section tag of %0X\n", 
            temp_int );
        }
        teller = teller + tds_read_unknown_section ( filein );
        break;

      case 0x4120:

        if ( debug ) {
          printf ( "        FACE_ARRAY section tag of %0X\n", 
            temp_int );
        }

        temp_pointer2 = tds_read_u_long_int ( filein );
        face_num_inc = ( int ) tds_read_u_short_int ( filein );
 
        for ( i = face_num; i < face_num + face_num_inc; i++ ) {
          face[0][i] = tds_read_u_short_int ( filein ) + cor3_num_base;
          face[1][i] = tds_read_u_short_int ( filein ) + cor3_num_base;
          face[2][i] = tds_read_u_short_int ( filein ) + cor3_num_base;
          face_order[i] = 3;
          face_flags[i] = tds_read_u_short_int ( filein );
/*
  Color is given per face, and as 24 bit RGB data packed in one word.
  Extract RGB from the word, and assign R / 255 to each vertex.

  Just a guess, JVB, 30 June 2001.
*/
          temp_int = face_flags[i] & 0x000F;
          r = ( temp_int & 0x0004 ) >> 2;
          g = ( temp_int & 0x0002 ) >> 1;
          b = ( temp_int & 0x0001 );

          for ( j = 0; j < 3; j++ ) {
            vertex_rgb[0][j][i] = ( float ) r / 255.0;
            vertex_rgb[1][j][i] = ( float ) g / 255.0;
            vertex_rgb[2][j][i] = ( float ) b / 255.0;
          }

        }

        temp_int = tds_read_u_short_int ( filein );
        if ( temp_int == 0x4150 ) {
          for ( i = face_num; i < face_num + face_num_inc; i++ ) {
            face_smooth[i] = ( int ) tds_read_u_long_int ( filein ) 
              + cor3_num_base;
          }
        }
        face_num = face_num + face_num_inc;
        teller = ftell ( filein );
        break;

      case 0x4130:
        if ( debug ) {
          printf ( "        MSH_MAT_GROUP section tag of %0X\n", 
            temp_int );
        }
        teller = teller + tds_read_unknown_section ( filein );
        break;

      case 0x4140:
        if ( debug ) {
          printf ( "        TEX_VERTS section tag of %0X\n", 
            temp_int );
        }
        teller = teller + tds_read_tex_verts_section ( filein );
        break;

      case 0x4150:
        if ( debug ) {
          printf ( "        SMOOTH_GROUP section tag of %0X\n", 
            temp_int );
        }
        teller = teller + tds_read_unknown_section ( filein );
        break;

      case 0x4160:

        if ( debug ) {
          printf ( "        MESH_MATRIX section tag of %0X\n", 
            temp_int );
        }

        tds_read_u_long_int ( filein );

        for ( j = 0; j < 4; j++ ) {
          for ( i = 0; i < 3; i++ ) {
            transform_matrix[j][i] = float_read ( filein );
          }
        }
        transform_matrix[0][3] = 0.0;
        transform_matrix[1][3] = 0.0;
        transform_matrix[2][3] = 0.0;
        transform_matrix[3][3] = 0.0;

        teller = teller + 12 * sizeof ( float );
        break;

      case 0x4165:

        if ( debug ) {
          printf ( "        MESH_COLOR section tag of %0X\n", temp_int );
        }

        chunk_size = tds_read_u_long_int ( filein );

        if ( chunk_size == 7 ) {
          color_index = fgetc ( filein );
          teller = teller + 5;
        }
        else {
          color_index = tds_read_u_short_int ( filein );
          teller = teller + 6;
        } 
        if ( debug ) {
          printf ( "        Color index set to %d\n", color_index );
        }
        break;

      case 0x4170:
        if ( debug ) {
          printf ( "        MESH_TEXTURE_INFO section tag of %0X\n", 
            temp_int );
        }
        teller = teller + tds_read_unknown_section ( filein );
        break;

      default:
        if ( debug ) {
          printf ( "        JUNK section tag of %0X\n", temp_int );
        }
        break;
    }
 
    if (  teller >= temp_pointer ) {
      end_found = TRUE;
    }

  }
 
  pointer = ( long int ) ( current_pointer + temp_pointer );
  fseek ( filein, pointer, SEEK_SET );

  return ( temp_pointer );
}
/******************************************************************************/

unsigned long tds_read_object_section ( FILE *filein )

/******************************************************************************/
{
  unsigned char       end_found = FALSE;
  unsigned long int   current_pointer;
  int                 int_val;
  long int            pointer;
  unsigned short int  temp_int;
  unsigned long int   temp_pointer;
  unsigned long int   teller;
 
  current_pointer = ftell ( filein ) - 2;
  temp_pointer = tds_read_u_long_int ( filein );
  teller = 6;
/*
  Why don't you read and save the name here?
*/
  int_val = tds_read_name ( filein );

  if ( int_val == -1 ) {
    if ( debug ) {
      printf ( "      Dummy Object found\n" );
    }
  }
  else {
    strcpy ( object_name, temp_name );
  }
 
  while ( end_found == FALSE ) {

    temp_int = tds_read_u_short_int ( filein );
    teller = teller + 2;

    switch ( temp_int ) {
      case 0x4700:
        if ( debug ) {
          printf ( "      N_CAMERA section tag of %0X\n", temp_int );
        }
        teller = teller + tds_read_camera_section ( filein );
        break;
      case 0x4600:
        if ( debug ) {
          printf ( "      N_DIRECT_LIGHT section tag of %0X\n", temp_int );
        }
        teller = teller + tds_read_light_section ( filein );
        break;
      case 0x4100:
        if ( debug ) {
          printf ( "      OBJ_TRIMESH section tag of %0X\n", temp_int );
        }
        teller = teller + tds_read_obj_section ( filein );
        break;
      case 0x4010: 
        if ( debug ) {
          printf ( "      OBJ_HIDDEN section tag of %0X\n", temp_int );
        }
        teller = teller + tds_read_unknown_section ( filein );
        break;
      case 0x4012: 
        if ( debug ) {
          printf ( "      OBJ_DOESNT_CAST section tag of %0X\n", temp_int );
        }
        teller = teller + tds_read_unknown_section ( filein );
        break;
      default:
        break;
    }
 
    if ( teller >= temp_pointer ) {
      end_found = TRUE;
    }

  }
 
  pointer = ( long ) ( current_pointer + temp_pointer );

  fseek ( filein, pointer, SEEK_SET );

  return ( temp_pointer );
}
/******************************************************************************/

unsigned long int tds_read_tex_verts_section ( FILE *filein )

/******************************************************************************/
 
/*
  Purpose:
 
    TDS_READ_TEX_VERTS_SECTION reads the texture vertex data.
 
  Discussion:
 
    The texture vertex data seems to be associated with nodes.  This routine
    distributes that data to vertices (nodes as they make up a particular
    face).
 
  Modified:
 
    02 July 1999
 
  Author:
 
    John Burkardt
*/
{
  unsigned long int  current_pointer;
  int                icor3;
  long int           pointer;
  unsigned long int  temp_pointer;
  unsigned short int n2;
 
  current_pointer = ftell ( filein ) - 2;
  temp_pointer = tds_read_u_long_int ( filein );
 
  pointer = ( long int ) ( current_pointer + temp_pointer );

  n2 = tds_read_u_short_int ( filein );
 
  for ( icor3 = 0; icor3 < n2; icor3++ ) {
    cor3_tex_uv[0][icor3] = float_read ( filein );
    cor3_tex_uv[1][icor3] = float_read ( filein );
  }
 
  fseek ( filein, pointer, SEEK_SET );

  return ( temp_pointer );
}
/******************************************************************************/

unsigned long tds_read_texmap_section ( FILE *filein )

/******************************************************************************/
 
/*
  Purpose:

    TDS_READ_TEXMAP_SECTION tries to get the TEXMAP name from the TEXMAP section.
 
  Warning:

    The code has room for lots of textures.  In this routine, we behave as
    though there were only one, and we stick its name in the first name slot.
 
  Modified:
 
    30 June 1999

  Author:
 
    John Burkardt
*/
{
  unsigned long int  current_pointer;
  long int           pointer;
  int                teller;
  unsigned long int  temp_pointer;
 
  texture_num = texture_num + 1;
 
  current_pointer = ftell ( filein ) - 2;
  temp_pointer = tds_read_u_long_int ( filein );
 
  tds_read_u_short_int ( filein );
  tds_read_u_short_int ( filein );
  tds_read_u_short_int ( filein );
  tds_read_u_short_int ( filein );
 
/*
  This next short int should equal A300.
*/
  tds_read_u_short_int ( filein );
  tds_read_u_long_int ( filein );
/*
  Now read the TEXMAP file name.
*/
  teller = tds_read_long_name ( filein );

  if ( teller == -1 ) {
    if ( debug ) {
      printf ( "      No TEXMAP name found.\n" );
    }
  }
  else {
    strcpy ( texture_name[0], temp_name );
    if ( debug ) {
      printf ( "      TEXMAP name %s.\n", texture_name[0] );
    }
  }
 
  pointer = ( long ) ( current_pointer + temp_pointer );
  fseek ( filein, pointer, SEEK_SET );

  return ( temp_pointer );
}
/******************************************************************************/

unsigned short int tds_read_u_short_int ( FILE *filein )

/******************************************************************************/
{
  unsigned char  c1;
  unsigned char  c2;
  short int      ival;

  c1 = fgetc ( filein );
  c2 = fgetc ( filein );

  ival = c1 | ( c2 << 8 );

  return ival;
}
/******************************************************************************/

unsigned long tds_read_spot_section ( FILE *filein )

/******************************************************************************/
{
  unsigned long int  current_pointer;
  float              falloff;
  float              hotspot;
  long int           pointer;
  float              target[4];
  unsigned long int  temp_pointer;

  current_pointer = ftell ( filein ) - 2;
  temp_pointer = tds_read_u_long_int ( filein );
 
  target[0] = float_read ( filein );
  target[1] = float_read ( filein );
  target[2] = float_read ( filein );
  hotspot = float_read ( filein );
  falloff = float_read ( filein );
 
  if ( debug ) {
    printf ( "      The target of the spot is XYZ = %f %f %f.\n",
      target[0], target[1], target[2] );
    printf ( "      The hotspot of this light is %f.\n", hotspot );
    printf ( "      The falloff of this light is %f.\n", falloff );
  }
 
  pointer = ( long ) ( current_pointer + temp_pointer );

  fseek ( filein, pointer, SEEK_SET );

  return ( temp_pointer );
}
/******************************************************************************/

unsigned long int tds_read_unknown_section ( FILE *filein )

/******************************************************************************/
{
  unsigned long int  current_pointer;
  long int           pointer;
  unsigned long int  temp_pointer;
 
  current_pointer = ftell ( filein ) - 2;
  temp_pointer = tds_read_u_long_int ( filein );
 
  pointer = ( long int ) ( current_pointer + temp_pointer );

  fseek ( filein, pointer, SEEK_SET );

  return ( temp_pointer );
}
/******************************************************************************/

unsigned long tds_read_view_section ( FILE *filein, int *views_read )

/******************************************************************************/
{
  unsigned long int   current_pointer;
  unsigned char       end_found = FALSE;
  long int            pointer;
  unsigned short int  temp_int;
  unsigned long int   temp_pointer;
  unsigned long int   teller;
 
  current_pointer = ftell ( filein ) - 2;
  temp_pointer = tds_read_u_long_int ( filein );
  teller = 6;
 
  while ( end_found == FALSE ) {

    temp_int = tds_read_u_short_int ( filein );
    teller = teller + 2;

    switch ( temp_int ) {
      case 0x7012:
        if ( debug ) {
          printf ( "     VIEWPORT_DATA_3 section tag of %0X\n", temp_int );
        }
        teller = teller + tds_read_vp_section ( filein, views_read );
        break;
      case 0x7011:
        if ( debug ) {
          printf ( "     VIEWPORT_DATA section tag of %0X\n", temp_int );
        }
        teller = teller + tds_read_unknown_section ( filein );
        break;
      case 0x7020:
        if ( debug ) {
          printf ( "     VIEWPORT_SIZE section tag of %0X\n", temp_int );
        }
        teller = teller + tds_read_vp_section ( filein, views_read );
        break;
      default:
        break;
    }
 
    if ( teller >= temp_pointer ) {
      end_found = TRUE;
    }
 
    if ( *views_read > 3 ) {
      end_found = TRUE;
    }
  }
 
  pointer = ( long int ) ( current_pointer + temp_pointer );

  fseek ( filein, pointer, SEEK_SET );

  return ( temp_pointer );
}
/******************************************************************************/

unsigned long tds_read_vp_section ( FILE *filein, int *views_read )

/******************************************************************************/
{
  unsigned int       attribs;
  unsigned long int  current_pointer;
  int                i;
  int                int_val;
  long int           pointer;
  unsigned int       port;
  unsigned long int  temp_pointer;
  char              *viewports[11] = {
                      "Bogus",
                      "Top",
                      "Bottom",
                      "Left",
                      "Right",
                      "Front",
                      "Back",
                      "User",
                      "Camera",
                      "Light",
                      "Disabled"
                     };

  *views_read = *views_read + 1;
 
  current_pointer = ftell ( filein ) - 2;
  temp_pointer = tds_read_u_long_int ( filein );
 
  attribs = tds_read_u_short_int ( filein );

  if ( attribs == 3 ) {
    if ( debug ) {
      printf ( "<Snap> active in viewport.\n" );
    }
  }

  if ( attribs == 5 ) {
    if ( debug ) {
      printf ( "<Grid> active in viewport.\n" );
    }
  }
/* 
  Read 5 INTS to get to the viewport information. 
*/
  for ( i = 1; i < 6; i++ ) {
    tds_read_u_short_int ( filein ); 
  }

  port = tds_read_u_short_int ( filein );
/*
  Find camera section. 
*/
  if ( ( port == 0xffff ) || ( port == 0 ) ) {

    for ( i = 0; i < 12; i++ ) {
      tds_read_u_short_int ( filein );
    }
 
    int_val = tds_read_name (filein );
 
    if ( int_val == -1 ) {
      if ( debug ) {
        printf ( "      No Camera name found\n" );
      }
    }

    port = 0x0008;
  }
 
  if ( debug ) {
    printf ( "Reading [%s] information with tag:%d\n", viewports[port], port );
  }
 
  pointer = ( long int ) ( current_pointer + temp_pointer );

  fseek ( filein, pointer, SEEK_SET ); 

  return ( temp_pointer );
}
/******************************************************************************/

int tds_write ( FILE *fileout )

/******************************************************************************/

/*
  Purpose:

    TDS_WRITE writes graphics information to a 3D Studio Max 3DS file.

  Modified:

    14 October 1998

  Author:

    John Burkardt

*/
{
  float               float_val;
  int                 i;
  int                 icor3;
  int                 iface;
  int                 j;
  long int            l0002;
  long int            l0100;
  long int            l3d3d;
  long int            l3d3e;
  long int            l4000;
  long int            l4100;
  long int            l4110;
  long int            l4120;
  long int            l4150;
  long int            l4160;
  long int            l4d4d;
  long int            lb000;
  long int            lb002;
  long int            lb00a;
  long int            lb008;
  long int            lb009;
  long int            lb010;
  long int            lb013;
  long int            lb020;
  long int            lb021;
  long int            lb022;
  long int            lb030;
  long int            long_int_val;
  int                 name_length;
  short int           short_int_val;
  unsigned short int  u_short_int_val;

  bytes_num = 0;
  name_length = strlen ( object_name );

  l0002 = 10;

  l4150 = 2 + 4 + face_num * 4;
  l4120 = 2 + 4 + 2 + 4 * face_num * 2 + l4150;
  l4160 = 2 + 4 + 4 * 12;
  l4110 = 2 + 4 + 2 + cor3_num * 3 * 4;
  l4100 = 2 + 4 + l4110 + l4160 + l4120;
  l4000 = 2 + 4 + ( name_length + 1 ) + l4100;
  l0100 = 2 + 4 + 4;
  l3d3e = 2 + 4 + 4;
  l3d3d = 2 + 4 + l3d3e + l0100 + l4000;

  lb022 = 2 + 4 + 32;
  lb021 = 2 + 4 + 9 * 4;
  lb020 = 2 + 4 + 8 * 4;
  lb013 = 2 + 4 + 6 * 2;
  lb010 = 2 + 4 + ( name_length + 1 ) + 3 * 2;
  lb030 = 2 + 4 + 2;
  lb002 = 2 + 4 + lb030 + lb010 + lb013 + lb020 + lb021 + lb022;
  lb009 = 2 + 4 + 4;
  lb008 = 2 + 4 + 2 * 4;
  lb00a = 2 + 4 + 2 + 9 + 2 * 2;
  lb000 = 2 + 4 + lb00a + lb008 + lb009 + lb002;

  l4d4d = 2 + 4 + l0002 + l3d3d + lb000;
/*  
  M3DMAGIC begin.
    tag, size.
*/
  short_int_val = ( short ) 0x4d4d;
  bytes_num = bytes_num + short_int_write ( fileout, short_int_val );
  bytes_num = bytes_num + long_int_write ( fileout, l4d4d );
/*
  M3D_VERSION begin.
    tag, size, version.
*/
  short_int_val = ( short ) 0x0002;
  bytes_num = bytes_num + short_int_write ( fileout, short_int_val );
  bytes_num = bytes_num + long_int_write ( fileout, l0002 );
  long_int_val = 3;
  bytes_num = bytes_num + long_int_write ( fileout, long_int_val );
/*  
  M3D_VERSION end.
  MDATA begin.
    tag, size.
*/
  short_int_val = ( short ) 0x3d3d;
  bytes_num = bytes_num + short_int_write ( fileout, short_int_val );
  bytes_num = bytes_num + long_int_write ( fileout, l3d3d );
/*  
  MESH_VERSION begin.
    tag, size, version.
*/
  short_int_val = ( short ) 0x3d3e;
  bytes_num = bytes_num + short_int_write ( fileout, short_int_val );
  bytes_num = bytes_num + long_int_write ( fileout, l3d3e );
  long_int_val = 3;
  bytes_num = bytes_num + long_int_write ( fileout, long_int_val );
/*  
  MESH_VERSION end.  
  MASTER_SCALE begin.  
    tag, size, scale.
*/
  short_int_val = ( short ) 0x0100;
  bytes_num = bytes_num + short_int_write ( fileout, short_int_val );
  bytes_num = bytes_num + long_int_write ( fileout, l0100 );
  float_val = 1.0;
  bytes_num = bytes_num + float_write ( fileout, float_val );
/*
  MASTER_SCALE end. 
  NAMED_OBJECT begin. 
    tag, size, name. 
*/
  short_int_val = ( short ) 0x4000;
  bytes_num = bytes_num + short_int_write ( fileout, short_int_val );
  bytes_num = bytes_num + long_int_write ( fileout, l4000 );
  bytes_num = bytes_num + tds_write_string ( fileout, object_name );
/*  
  N_TRI_OBJECT begin.  
    tag, size.
*/
  short_int_val = ( short ) 0x4100;
  bytes_num = bytes_num + short_int_write ( fileout, short_int_val );
  bytes_num = bytes_num + long_int_write ( fileout, l4100 );
/*
  POINT_ARRAY begin.  
    tag, size, number of points, coordinates of points.
  Warning! number of points could exceed a short!
*/
  short_int_val = ( short ) 0x4110;
  bytes_num = bytes_num + short_int_write ( fileout, short_int_val );
  bytes_num = bytes_num + long_int_write ( fileout, l4110 );

  u_short_int_val = ( unsigned short ) cor3_num;
  bytes_num = bytes_num + tds_write_u_short_int ( fileout, u_short_int_val );

  for ( icor3 = 0; icor3 < cor3_num; icor3++ ) {
    for ( j = 0; j < 3; j++ ) {
      bytes_num = bytes_num + float_write ( fileout, cor3[j][icor3] );
    }
  }
/*
  POINT_ARRAY end.
  MESH_MATRIX begin.  
    tag, size, 4 by 3 matrix.
*/
  short_int_val = ( short ) 0x4160;
  bytes_num = bytes_num + short_int_write ( fileout, short_int_val );
  bytes_num = bytes_num + long_int_write ( fileout, l4160 );

  for ( i = 0; i < 4; i++ ) {
    for ( j = 0; j < 3; j++ ) {
      float_val = transform_matrix[i][j];
      bytes_num = bytes_num + float_write ( fileout, float_val );
    }
  }
/*
  MESH_MATRIX end.  
  FACE_ARRAY begin. 
    tag, size, number of faces, nodes per face. 
  Warning: number of faces could exceed a short!
*/
  short_int_val = ( short ) 0x4120;
  bytes_num = bytes_num + short_int_write ( fileout, short_int_val );
  bytes_num = bytes_num + long_int_write ( fileout, l4120 );

  u_short_int_val = ( unsigned short ) face_num;
  bytes_num = bytes_num + tds_write_u_short_int ( fileout, u_short_int_val );

  for ( iface = 0; iface < face_num; iface++ ) {
    for ( j = 0; j < 3; j++ ) {
      short_int_val = face[j][iface];
      bytes_num = bytes_num + short_int_write ( fileout, short_int_val );
    }
    short_int_val = face_flags[iface];
    bytes_num = bytes_num + short_int_write ( fileout, short_int_val );
  }
/*
  SMOOTH_GROUP begin.
    tag, size, group for each face.
*/
  short_int_val = ( short ) 0x4150;
  bytes_num = bytes_num + short_int_write ( fileout, short_int_val );
  bytes_num = bytes_num + long_int_write ( fileout, l4150 );

  for ( iface = 0; iface < face_num; iface++ ) {
    long_int_val = face_smooth[iface];
    bytes_num = bytes_num + long_int_write ( fileout, long_int_val );
  }
/*
  SMOOTH_GROUP end.
  FACE_ARRAY end.
  N_TRI_OBJECT end.
  NAMED_OBJECT end.
  MDATA end. 
  KFDATA begin.
*/
  short_int_val = ( short ) 0xb000;
  bytes_num = bytes_num + short_int_write ( fileout, short_int_val );
  bytes_num = bytes_num + long_int_write ( fileout, lb000 );
/*
  KFHDR begin.  
    tag, size, revision, filename, animlen.
*/
  short_int_val = ( short ) 0xb00a;
  bytes_num = bytes_num + short_int_write ( fileout, short_int_val );
  bytes_num = bytes_num + long_int_write ( fileout, lb00a );
  short_int_val = 5;
  bytes_num = bytes_num + short_int_write ( fileout, short_int_val );
  bytes_num = bytes_num + tds_write_string ( fileout, "MAXSCENE" );
  short_int_val = 100;
  bytes_num = bytes_num + short_int_write ( fileout, short_int_val );
  short_int_val = 0;
  bytes_num = bytes_num + short_int_write ( fileout, short_int_val );
/*
  KFHDR end.  
  KFSEG begin.  
    tag, size, start, end.
*/
  short_int_val = ( short ) 0xb008;
  bytes_num = bytes_num + short_int_write ( fileout, short_int_val );
  bytes_num = bytes_num + long_int_write ( fileout, lb008 );
  long_int_val = 0;
  bytes_num = bytes_num + long_int_write ( fileout, long_int_val );
  long_int_val = 100;
  bytes_num = bytes_num + long_int_write ( fileout, long_int_val );
/*
  KFSEG end.  
  KFCURTIME begin.
    tag, size, current_frame.
*/
  short_int_val = ( short ) 0xb009;
  bytes_num = bytes_num + short_int_write ( fileout, short_int_val );
  bytes_num = bytes_num + long_int_write ( fileout, lb009 );
  long_int_val = 0;
  bytes_num = bytes_num + long_int_write ( fileout, long_int_val );
/*
  KFCURTIME end.
  OBJECT_NODE_TAG begin.
    tag, size.  
*/
  short_int_val = ( short ) 0xb002;
  bytes_num = bytes_num + short_int_write ( fileout, short_int_val );
  bytes_num = bytes_num + long_int_write ( fileout, lb002 );
/*
  NODE_ID begin.
    tag, size, id.
*/
  short_int_val = ( short ) 0xb030;
  bytes_num = bytes_num + short_int_write ( fileout, short_int_val );
  bytes_num = bytes_num + long_int_write ( fileout, lb030 );
  short_int_val = 0;
  bytes_num = bytes_num + short_int_write ( fileout, short_int_val );
/*
  NODE_ID end.  
  NODE_HDR begin. 
    tag, size, object_name, flag1, flag2, hierarchy.
*/
  short_int_val = ( short ) 0xb010;
  bytes_num = bytes_num + short_int_write ( fileout, short_int_val );
  bytes_num = bytes_num + long_int_write ( fileout, lb010 );
  bytes_num = bytes_num + tds_write_string ( fileout, object_name );
  short_int_val = 16384;
  bytes_num = bytes_num + short_int_write ( fileout, short_int_val );
  short_int_val = 0;
  bytes_num = bytes_num + short_int_write ( fileout, short_int_val );
  short_int_val = -1;
  bytes_num = bytes_num + short_int_write ( fileout, short_int_val );
/*
  NODE_HDR end. 
  PIVOT begin. 
    tag, size, pivot_x, pivot_y, pivot_z.
*/
  short_int_val = ( short ) 0xb013;
  bytes_num = bytes_num + short_int_write ( fileout, short_int_val );
  bytes_num = bytes_num + long_int_write ( fileout, lb013 );
  for ( i = 0; i < 3; i++ ) {
    float_val = pivot[i];
    bytes_num = bytes_num + float_write ( fileout, float_val );
  }
/*
  PIVOT end. 
  POS_TRACK_TAG begin.  
    tag, size, flag, i1, i2, i3, i4, i5, i6, frame, l1, pos_x, pos_y, pos_z.
*/
  short_int_val = ( short ) 0xb020;
  bytes_num = bytes_num + short_int_write ( fileout, short_int_val );
  bytes_num = bytes_num + long_int_write ( fileout, lb020 );
  short_int_val = 0;
  bytes_num = bytes_num + short_int_write ( fileout, short_int_val );
  short_int_val = 0;
  bytes_num = bytes_num + short_int_write ( fileout, short_int_val );
  short_int_val = 0;
  bytes_num = bytes_num + short_int_write ( fileout, short_int_val );
  short_int_val = 0;
  bytes_num = bytes_num + short_int_write ( fileout, short_int_val );
  short_int_val = 0;
  bytes_num = bytes_num + short_int_write ( fileout, short_int_val );
  short_int_val = 1;
  bytes_num = bytes_num + short_int_write ( fileout, short_int_val );
  short_int_val = 0;
  bytes_num = bytes_num + short_int_write ( fileout, short_int_val );
  short_int_val = 0;
  bytes_num = bytes_num + short_int_write ( fileout, short_int_val );
  long_int_val = 0;
  bytes_num = bytes_num + long_int_write ( fileout, long_int_val );
  for ( i = 0; i < 3; i++ ) {
    float_val = origin[i];
    bytes_num = bytes_num + float_write ( fileout, float_val );
  }
/*
  POS_TRACK_TAG end. 
  ROT_TRACK_TAG begin. 
    tag, size, i1, i2, i3, i4, i5, i6, i7, i8, l1, rad, axis_x, axis_y, axis_z. 
*/
  short_int_val = ( short ) 0xb021;
  bytes_num = bytes_num + short_int_write ( fileout, short_int_val );
  bytes_num = bytes_num + long_int_write ( fileout, lb021 );
  short_int_val = 0;
  bytes_num = bytes_num + short_int_write ( fileout, short_int_val );
  short_int_val = 0;
  bytes_num = bytes_num + short_int_write ( fileout, short_int_val );
  short_int_val = 0;
  bytes_num = bytes_num + short_int_write ( fileout, short_int_val );
  short_int_val = 0;
  bytes_num = bytes_num + short_int_write ( fileout, short_int_val );
  short_int_val = 0;
  bytes_num = bytes_num + short_int_write ( fileout, short_int_val );
  short_int_val = 1;
  bytes_num = bytes_num + short_int_write ( fileout, short_int_val );
  short_int_val = 0;
  bytes_num = bytes_num + short_int_write ( fileout, short_int_val );
  short_int_val = 0;
  bytes_num = bytes_num + short_int_write ( fileout, short_int_val );
  long_int_val = 0;
  bytes_num = bytes_num + long_int_write ( fileout, long_int_val );
  float_val = 0.0;
  bytes_num = bytes_num + float_write ( fileout, float_val );
  bytes_num = bytes_num + float_write ( fileout, float_val );
  bytes_num = bytes_num + float_write ( fileout, float_val );
  bytes_num = bytes_num + float_write ( fileout, float_val );
/*
  ROT_TRACK_TAG end. 
  SCL_TRACK_TAG begin.  
    tag, size, i1, i2, i3, i4, i5, i6, i7, i8, l1, scale_x, scale_y, scale_z.
*/
  short_int_val = ( short ) 0xb022;
  bytes_num = bytes_num + short_int_write ( fileout, short_int_val );
  bytes_num = bytes_num + long_int_write ( fileout, lb022 );
  short_int_val = 0;
  bytes_num = bytes_num + short_int_write ( fileout, short_int_val );
  short_int_val = 0;
  bytes_num = bytes_num + short_int_write ( fileout, short_int_val );
  short_int_val = 0;
  bytes_num = bytes_num + short_int_write ( fileout, short_int_val );
  short_int_val = 0;
  bytes_num = bytes_num + short_int_write ( fileout, short_int_val );
  short_int_val = 0;
  bytes_num = bytes_num + short_int_write ( fileout, short_int_val );
  short_int_val = 1;
  bytes_num = bytes_num + short_int_write ( fileout, short_int_val );
  short_int_val = 0;
  bytes_num = bytes_num + short_int_write ( fileout, short_int_val );
  short_int_val = 0;
  bytes_num = bytes_num + short_int_write ( fileout, short_int_val );
  long_int_val = 0;
  bytes_num = bytes_num + long_int_write ( fileout, long_int_val );
  float_val = 1.0;
  bytes_num = bytes_num + float_write ( fileout, float_val );
  bytes_num = bytes_num + float_write ( fileout, float_val );
  bytes_num = bytes_num + float_write ( fileout, float_val );
/*  
  SCL_TRACK_TAG end.
  OBJECT_NODE_TAG end.
  KFDATA end.
  M3DMAGIC end. 
*/

/*
  Report.
*/
  printf ( "TDS_WRITE wrote %d bytes.\n", bytes_num );

  return SUCCESS;
}
/******************************************************************************/

int tds_write_string ( FILE *fileout, char *string )

/******************************************************************************/

/*
  Modified:

    23 September 1998

  Author:

    John Burkardt
*/
{
  char *c;
  int   nchar;

  nchar = 0;

  for ( c = string; nchar < 12; c++ ) {

    fputc ( *c, fileout );
    nchar = nchar + 1;

    if  ( *c == 0 ) {
      return nchar;
    }

  }

  return nchar;
}
/******************************************************************************/

int tds_write_u_short_int ( FILE *fileout, unsigned short int short_int_val )

/******************************************************************************/

/*
  Modified:

    14 October 1998

  Author:

    John Burkardt
*/
{
  union {
    unsigned short int yint;
    char ychar[2];
  } y;

  y.yint = short_int_val;

  if ( byte_swap == TRUE ) {
    fputc ( y.ychar[1], fileout );
    fputc ( y.ychar[0], fileout );
  }
  else {
    fputc ( y.ychar[0], fileout );
    fputc ( y.ychar[1], fileout );
  }

  return 2;
}
/**********************************************************************/

int tec_write ( FILE *fileout )

/**********************************************************************/

/*
  Purpose:

    TEC_WRITE writes graphics information to a TECPLOT file.

  Discussion:

    The file format used is appropriate for 3D finite element surface 
    zone data.  Polygons are decomposed into triangles where necessary.

  Example:

    TITLE = "cube.tec created by IVCON."
    VARIABLES = "X", "Y", "Z", "R", "G", "B"
    ZONE T="TRIANGLES", N=8, E=12, F=FEPOINT, ET=TRIANGLE
    0.0 0.0 0.0 0.0 0.0 0.0
    1.0 0.0 0.0 1.0 0.0 0.0
    1.0 1.0 0.0 1.0 1.0 0.0
    0.0 1.0 0.0 0.0 1.0 0.0
    0.0 0.0 1.0 0.0 0.0 1.0
    1.0 0.0 1.0 1.0 0.0 1.0
    1.0 1.0 1.0 1.0 1.0 1.0
    0.0 1.0 1.0 0.0 1.0 1.0
    1 4 2
    2 4 3
    1 5 8
    1 2 5
    2 6 5
    2 3 6
    3 7 6
    3 4 7
    4 8 7
    4 1 8
    5 6 8
    6 7 8

  Modified:

    09 June 1999

  Author:

    John Burkardt
*/
{
  float b;
  int face2[3];
  float g;
  int icor3;
  int iface;
  int imat;
  int j;
  int face_num2;
  int text_num;
  float r;
/*
  Determine the number of triangular faces.
*/
  face_num2 = 0;
  for ( iface = 0; iface < face_num; iface++ ) {
    for ( j = 0; j < face_order[iface] - 2; j++ ) {
      face_num2 = face_num2 + 1;
    }
  }

  text_num = 0;

  fprintf ( fileout, "\"%s created by IVCON.\"\n", fileout_name );
  fprintf ( fileout, "VARIABLES = \"X\", \"Y\", \"Z\", \"R\", \"G\", \"B\"\n" );
  fprintf ( fileout, 
    "ZONE T=\"TRIANGLES\", N=%d, E=%d, F=FEPOINT, ET=TRIANGLE\n",
    cor3_num, face_num2 );

  text_num = text_num + 3;
/*
  Write out X, Y, Z, R, G, B per node.
*/
  for ( icor3 = 0; icor3 < cor3_num; icor3++ ) {
    imat = cor3_material[icor3];
    r = material_rgba[0][imat];
    g = material_rgba[1][imat];
    b = material_rgba[2][imat];
    fprintf ( fileout, "%f %f %f %f %f %f\n", cor3[0][icor3], cor3[1][icor3],
      cor3[2][icor3], r, g, b );
    text_num = text_num + 1;
  }
/*
  Do the next face.
*/
  for ( iface = 0; iface < face_num; iface++ ) {
/*
  Break the face up into triangles, anchored at node 1.
*/
    for ( j = 0; j < face_order[iface] - 2; j++ ) {

      face2[0] = face[  0][iface] + 1;
      face2[1] = face[j+1][iface] + 1;
      face2[2] = face[j+2][iface] + 1;

      fprintf ( fileout, "%d %d %d\n", face2[0], face2[1], face2[2] );
      text_num = text_num + 1;

    }

  }
/*
  Report.
*/
  printf ( "\n" );
  printf ( "TEC_WRITE - Wrote %d text lines.\n", text_num );

  return SUCCESS;
}

/*********************************************************************/

void tmat_init ( float a[4][4] )

/*********************************************************************/

/*
  Purpose:

    TMAT_INIT initializes the geometric transformation matrix.

  Definition:

    The geometric transformation matrix can be thought of as a 4 by 4
    matrix "A" having components:

      r11 r12 r13 t1
      r21 r22 r23 t2
      r31 r32 r33 t3
        0   0   0  1

    This matrix encodes the rotations, scalings and translations that
    are applied to graphical objects.

    A point P = (x,y,z) is rewritten in "homogeneous coordinates" as 
    PH = (x,y,z,1).  Then to apply the transformations encoded in A to 
    the point P, we simply compute A * PH.

    Individual transformations, such as a scaling, can be represented
    by simple versions of the transformation matrix.  If the matrix
    A represents the current set of transformations, and we wish to 
    apply a new transformation B, { the original points are
    transformed twice:  B * ( A * PH ).  The new transformation B can
    be combined with the original one A, to give a single matrix C that
    encodes both transformations: C = B * A.

  Modified:

    19 October 1998

  Author:

    John Burkardt

  Reference:

    Foley, van Dam, Feiner, Hughes,
    Computer Graphics, Principles and Practice,
    Addison Wesley, Second Edition, 1990.

  Parameters:

    Input, float A[4][4], the geometric transformation matrix.
*/
{
  int i;
  int j;

  for ( i = 0; i < 4; i++ ) {
    for ( j = 0; j < 4; j++ ) {
      if ( i == j ) {
        a[i][j] = 1.0;
      }
      else {
        a[i][j] = 0.0;
      }
    }
  }
  return;
}
/*********************************************************************/

void tmat_mxm ( float a[4][4], float b[4][4], float c[4][4] )

/*********************************************************************/

/*
  Purpose:

    TMAT_MXM multiplies two geometric transformation matrices.

  Note:

    The product is accumulated in a temporary array, and { assigned
    to the result.  Therefore, it is legal for any two, or all three,
    of the arguments to share memory.

  Modified:

    19 October 1998

  Author:

    John Burkardt

  Reference:

    Foley, van Dam, Feiner, Hughes,
    Computer Graphics, Principles and Practice,
    Addison Wesley, Second Edition, 1990.

  Parameters:

    Input, float A[4][4], the first geometric transformation matrix.

    Input, float B[4][4], the second geometric transformation matrix.

    Output, float C[4][4], the product A * B.
*/
{
  float d[4][4];
  int i;
  int j;
  int k;

  for ( i = 0; i < 4; i++ ) {
    for ( k = 0; k < 4; k++ ) {
      d[i][k] = 0.0;
      for ( j = 0; j < 4; j++ ) {
        d[i][k] = d[i][k] + a[i][j] * b[j][k];
      }
    }
  }

  for ( i = 0; i < 4; i++ ) {
    for ( j = 0; j < 4; j++ ) {
      c[i][j] = d[i][j];
    }
  }
  return;
}
/*********************************************************************/

void tmat_mxp ( float a[4][4], float x[4], float y[4] )

/*********************************************************************/

/*
  Purpose:

    TMAT_MXP multiplies a geometric transformation matrix times a point.

  Modified:

    19 October 1998

  Author:

    John Burkardt

  Reference:

    Foley, van Dam, Feiner, Hughes,
    Computer Graphics, Principles and Practice,
    Addison Wesley, Second Edition, 1990.

  Parameters:

    Input, float A[4][4], the geometric transformation matrix.

    Input, float X[4], the point to be multiplied.  The fourth component
    of X is implicitly assigned the value of 1.

    Output, float Y[4], the result of A*X.  The product is accumulated in 
    a temporary vector, and { assigned to the result.  Therefore, it 
    is legal for X and Y to share memory.
*/
{
  int i;
  int j;
  float z[4];

  for ( i = 0; i < 3; i++ ) {
    z[i] = a[i][3];
    for ( j = 0; j < 3; j++ ) {
      z[i] = z[i] + a[i][j] * x[j];
    }
  }

  for ( i = 0; i < 3; i++ ) {
    y[i] = z[i];
  }
  return;
}
/*********************************************************************/

void tmat_mxp2 ( float a[4][4], float x[][3], float y[][3], int n )

/*********************************************************************/

/*
  Purpose:

    TMAT_MXP2 multiplies a geometric transformation matrix times N points.

  Modified:

    20 October 1998

  Author:

    John Burkardt

  Reference:

    Foley, van Dam, Feiner, Hughes,
    Computer Graphics, Principles and Practice,
    Addison Wesley, Second Edition, 1990.

  Parameters:

    Input, float A[4][4], the geometric transformation matrix.

    Input, float X[N][3], the points to be multiplied.  

    Output, float Y[N][3], the transformed points.  Each product is 
    accumulated in a temporary vector, and { assigned to the
    result.  Therefore, it is legal for X and Y to share memory.

*/
{
  int i;
  int j;
  int k;
  float z[4];

  for ( k = 0; k < n; k++ ) {

    for ( i = 0; i < 3; i++ ) {
      z[i] = a[i][3];
      for ( j = 0; j < 3; j++ ) {
        z[i] = z[i] + a[i][j] * x[k][j];
      }
    }

    for ( i = 0; i < 3; i++ ) {
      y[k][i] = z[i];
    }

  }
  return;
}
/*********************************************************************/

void tmat_mxv ( float a[4][4], float x[4], float y[4] )

/*********************************************************************/

/*
  Purpose:

    TMAT_MXV multiplies a geometric transformation matrix times a vector.

  Modified:

    12 August 1999

  Author:

    John Burkardt

  Reference:

    Foley, van Dam, Feiner, Hughes,
    Computer Graphics, Principles and Practice,
    Addison Wesley, Second Edition, 1990.

  Parameters:

    Input, float A[4][4], the geometric transformation matrix.

    Input, float X[3], the vector to be multiplied.  The fourth component
    of X is implicitly assigned the value of 1.

    Output, float Y[3], the result of A*X.  The product is accumulated in 
    a temporary vector, and assigned to the result.  Therefore, it 
    is legal for X and Y to share memory.
*/
{
  int i;
  int j;
  float z[4];

  for ( i = 0; i < 3; i++ ) {
    z[i] = 0.0;
    for ( j = 0; j < 3; j++ ) {
      z[i] = z[i] + a[i][j] * x[j];
    }
    z[i] = z[i] + a[i][3];
  }

  for ( i = 0; i < 3; i++ ) {
    y[i] = z[i];
  }
  return;
}
/*********************************************************************/

void tmat_rot_axis ( float a[4][4], float b[4][4], float angle, 
  char axis )

/*********************************************************************/

/*
  Purpose:

    TMAT_ROT_AXIS applies an axis rotation to the geometric transformation matrix.

  Modified:

    19 April 1999

  Author:

    John Burkardt

  Reference:

    Foley, van Dam, Feiner, Hughes,
    Computer Graphics, Principles and Practice,
    Addison Wesley, Second Edition, 1990.

  Parameters:

    Input, float A[4][4], the current geometric transformation matrix.

    Output, float B[4][4], the modified geometric transformation matrix.
    A and B may share the same memory.

    Input, float ANGLE, the angle, in degrees, of the rotation.

    Input, character AXIS, is 'X', 'Y' or 'Z', specifying the coordinate
    axis about which the rotation occurs.
*/
{
  float c[4][4];
  float d[4][4];
  int i;
  int j;
  float theta;

  theta = angle * DEG_TO_RAD;

  tmat_init ( c );

  if ( axis == 'X' || axis == 'x' ) {
    c[1][1] =   cos ( theta );
    c[1][2] = - sin ( theta );
    c[2][1] =   sin ( theta );
    c[2][2] =   cos ( theta );
  }
  else if ( axis == 'Y' || axis == 'y' ) {
    c[0][0] =   cos ( theta );
    c[0][2] =   sin ( theta );
    c[2][0] = - sin ( theta );
    c[2][2] =   cos ( theta );
  }
  else if ( axis == 'Z' || axis == 'z' ) {
    c[0][0] =   cos ( theta );
    c[0][1] = - sin ( theta );
    c[1][0] =   sin ( theta );
    c[1][1] =   cos ( theta );
  }
  else {
    printf ( "\n" );
    printf ( "TMAT_ROT_AXIS - Fatal error!\n" );
    printf ( "  Illegal rotation axis: %c.\n", axis );
    printf ( "  Legal choices are 'X', 'Y', or 'Z'.\n" );
    return;
  }

  tmat_mxm ( c, a, d );

  for ( i = 0; i < 4; i++ ) {
    for ( j = 0; j < 4; j++ ) {
      b[i][j] = d[i][j];
    }
  }
  return;
}
/*********************************************************************/

void tmat_rot_vector ( float a[4][4], float b[4][4], float angle, 
  float v1, float v2, float v3 )

/*********************************************************************/

/*
  Purpose:

    TMAT_ROT_VECTOR applies a rotation about a vector to the geometric transformation matrix.

  Modified:

    27 July 1999

  Author:

    John Burkardt

  Reference:

    Foley, van Dam, Feiner, Hughes,
    Computer Graphics, Principles and Practice,
    Addison Wesley, Second Edition, 1990.

  Parameters:

    Input, float A[4][4], the current geometric transformation matrix.

    Output, float B[4][4], the modified geometric transformation matrix.
    A and B may share the same memory.

    Input, float ANGLE, the angle, in degrees, of the rotation.

    Input, float V1, V2, V3, the X, Y and Z coordinates of a (nonzero)
    point defining a vector from the origin.  The rotation will occur
    about this axis.
*/
{
  float c[4][4];
  float ca;
  float d[4][4];
  int i;
  int j;
  float sa;
  float theta;

  if ( v1 * v1 + v2 * v2 + v3 * v3 == 0.0 ) {
    return;
  }

  theta = angle * DEG_TO_RAD;

  tmat_init ( c );

  ca = cos ( theta );
  sa = sin ( theta );

  c[0][0] =                v1 * v1 + ca * ( 1.0 - v1 * v1 );
  c[0][1] = ( 1.0 - ca ) * v1 * v2 - sa * v3;
  c[0][2] = ( 1.0 - ca ) * v1 * v3 + sa * v2;

  c[1][0] = ( 1.0 - ca ) * v2 * v1 + sa * v3;
  c[1][1] =                v2 * v2 + ca * ( 1.0 - v2 * v2 );
  c[1][2] = ( 1.0 - ca ) * v2 * v3 - sa * v1;

  c[2][0] = ( 1.0 - ca ) * v3 * v1 - sa * v2;
  c[2][1] = ( 1.0 - ca ) * v3 * v2 + sa * v1;
  c[2][2] =                v3 * v3 + ca * ( 1.0 - v3 * v3 );

  tmat_mxm ( c, a, d );

  for ( i = 0; i < 4; i++ ) {
    for ( j = 0; j < 4; j++ ) {
      b[i][j] = d[i][j];
    }
  }
  return;
}
/*********************************************************************/

void tmat_scale ( float a[4][4], float b[4][4], float sx, float sy, 
  float sz )

/*********************************************************************/

/*
  Purpose:

    TMAT_SCALE applies a scaling to the geometric transformation matrix.

  Modified:

    19 October 1998

  Author:

    John Burkardt

  Reference:

    Foley, van Dam, Feiner, Hughes,
    Computer Graphics, Principles and Practice,
    Addison Wesley, Second Edition, 1990.

  Parameters:

    Input, float A[4][4], the current geometric transformation matrix.

    Output, float B[4][4], the modified geometric transformation matrix.
    A and B may share the same memory.

    Input, float SX, SY, SZ, the scalings to be applied to the X, Y and
    Z coordinates.
*/
{
  float c[4][4];
  float d[4][4];
  int i;
  int j;

  tmat_init ( c );

  c[0][0] = sx;
  c[1][1] = sy;
  c[2][2] = sz;

  tmat_mxm ( c, a, d );

  for ( i = 0; i < 4; i++ ) {
    for ( j = 0; j < 4; j++ ) {
      b[i][j] = d[i][j];
    }
  }
  return;
}
/*********************************************************************/

void tmat_shear ( float a[4][4], float b[4][4], char *axis, float s )

/*********************************************************************/

/*
  Purpose:

    TMAT_SHEAR applies a shear to the geometric transformation matrix.

  Modified:

    19 October 1998

  Author:

    John Burkardt

  Reference:

    Foley, van Dam, Feiner, Hughes,
    Computer Graphics, Principles and Practice,
    Addison Wesley, Second Edition, 1990.

  Parameters:

    Input, float A[4][4], the current geometric transformation matrix.

    Output, float B[4][4], the modified geometric transformation matrix.
    A and B may share the same memory.

    Input, character*3 AXIS, is 'XY', 'XZ', 'YX', 'YZ', 'ZX' or 'ZY',
    specifying the shear equation:

      XY:  x' = x + s * y;
      XZ:  x' = x + s * z;
      YX:  y' = y + s * x;
      YZ:  y' = y + s * z;
      ZX:  z' = z + s * x;
      ZY:  z' = z + s * y.

    Input, float S, the shear coefficient.
*/
{
  float c[4][4];
  float d[4][4];
  int i;
  int j;

  tmat_init ( c );

  if ( strcmp ( axis, "XY" ) == 0 || strcmp ( axis, "xy" ) == 0 ) {
    c[0][1] = s;
  }
  else if ( strcmp ( axis, "XZ" ) == 0 || strcmp ( axis, "xz" ) == 0 ) {
    c[0][2] = s;
  }
  else if ( strcmp ( axis, "YX" ) == 0 || strcmp ( axis, "yx" ) == 0 ) {
    c[1][0] = s;
  }
  else if ( strcmp ( axis, "YZ" ) == 0 || strcmp ( axis, "yz" ) == 0 ) {
    c[1][2] = s;
  }
  else if ( strcmp ( axis, "ZX" ) == 0 || strcmp ( axis, "zx" ) == 0 ) {
    c[2][0] = s;
  }
  else if ( strcmp ( axis, "ZY" ) == 0 || strcmp ( axis, "zy" ) == 0 ) {
    c[2][1] = s;
  }
  else {
    printf ( "\n" );
    printf ( "TMAT_SHEAR - Fatal error!\n" );
    printf ( "  Illegal shear axis: %s.\n", axis );
    printf ( "  Legal choices are XY, XZ, YX, YZ, ZX, or ZY.\n" );
    return;
  }

  tmat_mxm ( c, a, d );

  for ( i = 0; i < 4; i++ ) {
    for ( j = 0; j < 4; j++ ) {
      b[i][j] = d[i][j];
    }
  }
  return;
}
/*********************************************************************/

void tmat_trans ( float a[4][4], float b[4][4], float x, float y, 
  float z )

/*********************************************************************/

/*
  Purpose:

    TMAT_TRANS applies a translation to the geometric transformation matrix.

  Modified:

    19 October 1998

  Author:

    John Burkardt

  Reference:

    Foley, van Dam, Feiner, Hughes,
    Computer Graphics, Principles and Practice,
    Addison Wesley, Second Edition, 1990.

  Parameters:

    Input, float A[4][4], the current geometric transformation matrix.

    Output, float B[4][4], the modified transformation matrix.
    A and B may share the same memory.

    Input, float X, Y, Z, the translation.  This may be thought of as the
    point that the origin moves to under the translation.
*/
{
  int i;
  int j;

  for ( i = 0; i < 4; i++ ) {
    for ( j = 0; j < 4; j++ ) {
      b[i][j] = a[i][j];
    }
  }
  b[0][3] = b[0][3] + x;
  b[1][3] = b[1][3] + y;
  b[2][3] = b[2][3] + z;

  return;
}
/******************************************************************************/

int tria_read ( FILE *filein )

/******************************************************************************/

/*
  Purpose:
   
    TRIA_READ reads an ASCII triangle file.

  Example:

    12                    <-- Number of triangles

                          (x,y,z) and (nx,ny,nz) of normal vector at:

    0.0 0.0 0.0 0.3 0.3 0.3   node 1 of triangle 1.
    1.0 0.0 0.0 0.3 0.1 0.3   node 2 of triangle 1,
    0.0 1.0 0.0 0.3 0.1 0.3   node 3 of triangle 1,
    1.0 0.5 0.0 0.3 0.1 0.3   node 1 of triangle 2,
    ...
    0.0 0.5 0.5 0.3 0.1 0.3   node 3 of triangle 12.

  Modified:

    22 June 1999

  Author:
 
    John Burkardt
*/
{
  float cvec[3];
  int   icor3;
  int   iface;
  int   iface_hi;
  int   iface_lo;
  int   ivert;
  int   face_num2;
  float r1;
  float r2;
  float r3;
  float r4;
  float r5;
  float r6;
/*
  Get the number of triangles.
*/
  fgets ( input, LINE_MAX_LEN, filein );
  text_num = text_num + 1;
  sscanf ( input, "%d", &face_num2 );
/*
  For each triangle:
*/
  iface_lo = face_num;
  iface_hi = face_num + face_num2;

  for ( iface = iface_lo; iface < iface_hi; iface++ ) {

    if ( iface < FACE_MAX ) {
      face_order[iface] = 3;
      face_material[iface] = 0;
    }
/*
  For each face:
*/
    for ( ivert = 0; ivert < face_order[iface]; ivert++ ) {

      fgets ( input, LINE_MAX_LEN, filein );
      text_num = text_num + 1;
      sscanf ( input, "%e %e %e %e %e %e", &r1, &r2, &r3, &r4, &r5, &r6 ); 
 
      cvec[0] = r1;
      cvec[1] = r2;
      cvec[2] = r3;

      if ( cor3_num < 1000 ) {
        icor3 = rcol_find ( cor3, 3, cor3_num, cvec );
      }
      else {
        icor3 = -1;
      }

      if ( icor3 == -1 ) {
        icor3 = cor3_num;
        if ( cor3_num < COR3_MAX ) {
          cor3[0][cor3_num] = cvec[0];
          cor3[1][cor3_num] = cvec[1];
          cor3[2][cor3_num] = cvec[2];
        }
        cor3_num = cor3_num + 1;
      }
      else {
        dup_num = dup_num + 1;
      }

      if ( iface < FACE_MAX ) {

        face[ivert][iface] = icor3;
        vertex_material[ivert][iface] = 0;
        vertex_normal[0][ivert][iface] = r4;
        vertex_normal[1][ivert][iface] = r5;
        vertex_normal[2][ivert][iface] = r6;
      }

    }
  }
  face_num = face_num + face_num2;

  return SUCCESS;
}
/**********************************************************************/

int tria_write ( FILE *fileout )

/**********************************************************************/

/*
  Purpose:

    TRIA_WRITE writes the graphics data to an ASCII "triangle" file.

  Discussion:

    This is just a private format that Greg Hood requested from me.

  Example:

    12                    <-- Number of triangles

                          (x,y,z) and (nx,ny,nz) of normal vector at:

    0.0 0.0 0.0 0.3 0.3 0.3   node 1 of triangle 1.
    1.0 0.0 0.0 0.3 0.1 0.3   node 2 of triangle 1,
    0.0 1.0 0.0 0.3 0.1 0.3   node 3 of triangle 1,
    1.0 0.5 0.0 0.3 0.1 0.3   node 1 of triangle 2,
    ...
    0.0 0.5 0.5 0.3 0.1 0.3   node 3 of triangle 12.

  Modified:

    10 June 1999

  Author:

    John Burkardt
*/
{
  int face2[3];
  int icor3;
  int iface;
  int jlo;
  int k;
  int face_num2;
  int text_num;
  float nx;
  float ny;
  float nz;
  float x;
  float y;
  float z;

  text_num = 0;
/*
  Determine the number of triangular faces.
*/
  face_num2 = 0;
  for ( iface = 0; iface < face_num; iface++ ) {
    for ( jlo = 0; jlo < face_order[iface] - 2; jlo ++ ) {
      face_num2 = face_num2 + 1;
    }
  }

  fprintf ( fileout,  "%d\n", face_num2 );
  text_num = text_num + 1;
/*
  Do the next face.
*/
  for ( iface = 0; iface < face_num; iface++ ) {
/*
  Break the face up into triangles, anchored at node 1.
*/
    for ( jlo = 0; jlo < face_order[iface] - 2; jlo ++ ) {

      face2[0] = face[    0][iface];
      face2[1] = face[jlo+1][iface];
      face2[2] = face[jlo+2][iface];

      for ( k = 0; k < 3; k++ ) {

        icor3 = face2[k];

        x = cor3[0][icor3];
        y = cor3[1][icor3];
        z = cor3[2][icor3];

        nx = cor3_normal[0][icor3];
        ny = cor3_normal[1][icor3];
        nz = cor3_normal[2][icor3];

        fprintf ( fileout,  "%f %f %f %f %f %f\n", x, y, z, nx, ny, nz );

        text_num = text_num + 1;

      }

    }

  }
/*
  Report.
*/
  printf ( "\n" );
  printf ( "TRIA_WRITE - Wrote %d text lines.\n", text_num );

  return SUCCESS;
}
/******************************************************************************/

int trib_read ( FILE *filein )

/******************************************************************************/

/*
  Purpose:
   
    TRIB_READ reads a binary triangle file.

  Example:

    4 byte int = number of triangles

    For each triangular face:

      3 4-byte floats = coordinates of first node;
      3 4-byte floats = components of normal vector at first node;
      3 4-byte floats = coordinates of second node;
      3 4-byte floats = components of normal vector at second node;
      3 4-byte floats = coordinates of third node;
      3 4-byte floats = components of normal vector at third node.

  Modified:

    22 June 1999

  Author:
 
    John Burkardt
*/
{
  float cvec[3];
  int icor3;
  int i;
  int iface;
  int iface_hi;
  int iface_lo;
  int ivert;
  int face_num2;
/* 
  Read the number of triangles in the file.
*/
  face_num2 = long_int_read ( filein );
  bytes_num = bytes_num + 4;
/*
  For each (triangular) face,
    read the coordinates and normal vectors of three vertices,
*/
  iface_lo = face_num;
  iface_hi = face_num + face_num2;

  for ( iface = iface_lo; iface < iface_hi; iface++ ) {

    if ( iface < FACE_MAX ) {
      face_order[iface] = 3;
      face_material[iface] = 0;
    }

    for ( ivert = 0; ivert < face_order[iface]; ivert++ ) {

      for ( i = 0; i < 3; i++ ) {
        cvec[i] = float_read ( filein );
        bytes_num = bytes_num + 4;
      }

      if ( cor3_num < 1000 ) {
        icor3 = rcol_find ( cor3, 3, cor3_num, cvec );
      }
      else {
        icor3 = -1;
      }

      if ( icor3 == -1 ) {
        icor3 = cor3_num;
        if ( cor3_num < COR3_MAX ) {
          cor3[0][cor3_num] = cvec[0];
          cor3[1][cor3_num] = cvec[1];
          cor3[2][cor3_num] = cvec[2];
        }
        cor3_num = cor3_num + 1;
      }
      else {
        dup_num = dup_num + 1;
      }

      if ( iface < FACE_MAX ) {

        face[ivert][iface] = icor3;
        vertex_material[ivert][iface] = 0;

        for ( i = 0; i < 3; i++ ) {
          vertex_normal[i][ivert][iface] = float_read ( filein );
          bytes_num = bytes_num + 4;
        }

      }

    }
  }

  face_num = face_num + face_num2;

  return SUCCESS;
}
/**********************************************************************/

int trib_write ( FILE *fileout )

/**********************************************************************/

/*
  Purpose:

    TRIB_WRITE writes the graphics data to a binary "triangle" file.

  Discussion:

    This is just a private format that Greg Hood requested from me.

  Example:

    12   Number of triangles
    0.0  x at node 1, triangle 1,
    0.0  y at node 1, triangle 1,
    0.0  z at node 1, triangle 1,
    0.3  nx at node 1, triangle 1,
    0.3  ny at node 1, triangle 1,
    0.3  nz at node 1, triangle 1.
    1.0  x at node 2, triangle 1,
    ...
    0.7  nz at node 3, triangle 1.
    1.2  x at node 1, triangle 2,
    ...
    0.3  nz at node 3, triangle 2.
    9.3  x at node 1, triangle 3,
    ...
    0.3  nz at node 3, triangle 12.

  Modified:

    16 June 1999

  Author:

    John Burkardt
*/
{
  int face2[3];
  int icor3;
  int iface;
  int jlo;
  int k;
  int face_num2;
  float nx;
  float ny;
  float nz;
  float x;
  float y;
  float z;

  bytes_num = 0;
/*
  Determine the number of triangular faces.
*/
  face_num2 = 0;
  for ( iface = 0; iface < face_num; iface++ ) {
    for ( jlo = 0; jlo < face_order[iface] - 2; jlo ++ ) {
      face_num2 = face_num2 + 1;
    }
  }

  bytes_num = bytes_num + long_int_write ( fileout, face_num2 );
/*
  Do the next face.
*/
  for ( iface = 0; iface < face_num; iface++ ) {
/*
  Break the face up into triangles, anchored at node 1.
*/
    for ( jlo = 0; jlo < face_order[iface] - 2; jlo ++ ) {

      face2[0] = face[    0][iface];
      face2[1] = face[jlo+1][iface];
      face2[2] = face[jlo+2][iface];

      for ( k = 0; k < 3; k++ ) {

        icor3 = face2[k];

        x = cor3[0][icor3];
        y = cor3[1][icor3];
        z = cor3[2][icor3];

        nx = cor3_normal[0][icor3];
        ny = cor3_normal[1][icor3];
        nz = cor3_normal[2][icor3];

        bytes_num = bytes_num + float_write ( fileout, x );
        bytes_num = bytes_num + float_write ( fileout, y );
        bytes_num = bytes_num + float_write ( fileout, z );
        bytes_num = bytes_num + float_write ( fileout, nx );
        bytes_num = bytes_num + float_write ( fileout, ny );
        bytes_num = bytes_num + float_write ( fileout, nz );

      }

    }

  }
/*
  Report.
*/
  printf ( "\n" );
  printf ( "TRIB_WRITE - Wrote %d bytes.\n", bytes_num );

  return SUCCESS;
}
/******************************************************************************/

int txt_write ( FILE *fileout )

/******************************************************************************/

/*
  Purpose:
   
    TXT_WRITE writes the graphics data to a text file.

  Modified:

    25 June 1998

  Author:
 
    John Burkardt
*/
{
  int i;
  int iface;
  int iline;
  int imat;
  int ivert;
  int nitem;
  int text_num;

  text_num = 0;

  fprintf ( fileout, "%s created by IVCON.\n", fileout_name );
  fprintf ( fileout, "Original data in %s.\n", filein_name );
  fprintf ( fileout, "Object name is %s.\n", object_name );
  fprintf ( fileout, "Object origin at %f %f %f.\n", origin[0], origin[1],
    origin[2] );
  fprintf ( fileout, "Object pivot at %f %f %f.\n", pivot[0], pivot[1],
    pivot[2] );
  text_num = text_num + 5;
/*
  TRANSFORMATION MATRIX.
*/
  fprintf ( fileout, "\n" );
  fprintf ( fileout, "Transformation matrix:\n" );
  fprintf ( fileout, "\n" );
  text_num = text_num + 3;

  for ( i = 0; i < 4; i++ ) {
    fprintf ( fileout, "  %f %f %f %f\n", transform_matrix[i][0],
      transform_matrix[i][1], transform_matrix[i][2], transform_matrix[i][3] );
      text_num = text_num + 1;
  }
/*
  NODES.
*/
  fprintf ( fileout, "\n" );
  fprintf ( fileout, "  %d nodes.\n", cor3_num );
  text_num = text_num + 2;

  if ( cor3_num > 0 ) {

    fprintf ( fileout, "\n" );
    fprintf ( fileout, "  Node coordinate data:\n" );
    fprintf ( fileout, "\n" );
    text_num = text_num + 3;

    for ( i = 0; i < cor3_num; i++ ) {
      fprintf ( fileout, " %d %f %f %f\n ", i, cor3[0][i], cor3[1][i], 
        cor3[2][i] );
      text_num = text_num + 1;
    }

    fprintf ( fileout, "\n" );
    fprintf ( fileout, "  Node normal vectors:\n" );
    fprintf ( fileout, "\n" );
    text_num = text_num + 3;

    for ( i = 0; i < cor3_num; i++ ) {
      fprintf ( fileout, " %d %f %f %f\n ", i, cor3_normal[0][i], 
        cor3_normal[1][i], cor3_normal[2][i] );
      text_num = text_num + 1;
    }

    fprintf ( fileout, "\n" );
    fprintf ( fileout, "  Node materials:\n" );
    fprintf ( fileout, "\n" );
    text_num = text_num + 3;

    for ( i = 0; i < cor3_num; i++ ) {
      fprintf ( fileout, " %d %d\n ", i, cor3_material[i] );
      text_num = text_num + 1;
    }

    if ( texture_num > 0 ) {
      fprintf ( fileout, "\n" );
      fprintf ( fileout, "  Node texture coordinates:\n" );
      fprintf ( fileout, "\n" );
      text_num = text_num + 3;

      for ( i = 0; i < cor3_num; i++ ) {
        fprintf ( fileout, " %d %f %f\n ", i, cor3_tex_uv[0][i], 
          cor3_tex_uv[1][i] );
        text_num = text_num + 1;
      }
    }
  }
/*
  LINES.
*/
  fprintf ( fileout, "\n" );
  fprintf ( fileout, "  %d line data items.\n", line_num );
  text_num = text_num + 2;

  if ( line_num > 0 ) {

    fprintf ( fileout, "\n" );
    fprintf ( fileout, "  Line index data:\n" );
    fprintf ( fileout, "\n" );
    text_num = text_num + 3;

    nitem = 0;

    for ( iline = 0; iline < line_num; iline++ ) {

      fprintf ( fileout, " %d", line_dex[iline] );
      nitem = nitem + 1;

      if ( iline == line_num - 1 || line_dex[iline] == -1 || nitem >= 10 ) {
        nitem = 0;
        fprintf ( fileout, "\n" );
        text_num = text_num + 1;
      }

    }

    fprintf ( fileout, "\n" );
    fprintf ( fileout, "  Line materials:\n" );
    fprintf ( fileout, "\n" );
    text_num = text_num + 3;

    nitem = 0;

    for ( iline = 0; iline < line_num; iline++ ) {

      fprintf ( fileout, " %d", line_material[iline] );
      nitem = nitem + 1;

      if ( iline == line_num - 1 || line_material[iline] == -1 || nitem >= 10 ) {
        nitem = 0;
        fprintf ( fileout, "\n" );
        text_num = text_num + 1;
      }
    }

  }
/*
  COLOR DATA
*/
  fprintf ( fileout, "\n" );
  fprintf ( fileout, "  %d colors.\n", color_num );
  text_num = text_num + 2;
/*
  FACES.
*/
  fprintf ( fileout, "\n" );
  fprintf ( fileout, "  %d faces.\n", face_num );
  text_num = text_num + 2;

  if ( face_num > 0 ) {

    fprintf ( fileout, "\n" );
    fprintf ( fileout, "  Face, Material, Number of vertices, Smoothing, Flags:\n" );
    fprintf ( fileout, "\n" );
    text_num = text_num + 3;

    for ( iface = 0; iface < face_num; iface++ ) {
      fprintf ( fileout, " %d %d %d %d %d\n", iface, face_material[iface],
        face_order[iface], face_smooth[iface], face_flags[iface] );
      text_num = text_num + 1;
    }

    fprintf ( fileout, "\n" );
    fprintf ( fileout, "  Face, Vertices\n" );
    fprintf ( fileout, "\n" );
    text_num = text_num + 3;

    for ( iface = 0; iface < face_num; iface++ ) {

      fprintf ( fileout, "%d   ", iface );
      for ( ivert = 0; ivert < face_order[iface]; ivert++ ) {
        fprintf ( fileout, " %d", face[ivert][iface] );
      }

      fprintf ( fileout, "\n" );
      text_num = text_num + 1;
    }

    fprintf ( fileout, "\n" );
    fprintf ( fileout, "  Face normal vectors:\n" );
    fprintf ( fileout, "\n" );
    text_num = text_num + 3;

    for ( iface = 0; iface < face_num; iface++ ) {
      fprintf ( fileout, " %d %f %f %f\n", iface, face_normal[0][iface],
        face_normal[1][iface], face_normal[2][iface] );
      text_num = text_num + 1;
    }

    if ( texture_num > 0 ) {

      fprintf ( fileout, "\n" );
      fprintf ( fileout, "  Face texture coordinates:\n" );
      fprintf ( fileout, "\n" );
      text_num = text_num + 3;

      for ( iface = 0; iface < face_num; iface++ ) {
        fprintf ( fileout, " %d %f %f\n", iface, face_tex_uv[0][iface],
          face_tex_uv[1][iface] );
        text_num = text_num + 1;
      }
    }
  }
/*
  VERTICES.
*/
  if ( face_num > 0 ) {

    fprintf ( fileout, "\n" );
    fprintf ( fileout, "Vertex normal vectors:\n" );
    text_num = text_num + 2;

    for ( iface = 0; iface < face_num; iface++ ) {
      fprintf ( fileout, "\n" );
      text_num = text_num + 1;
      for ( ivert = 0; ivert < face_order[iface]; ivert++ ) {
        fprintf ( fileout, " %d %d %f %f %f\n", iface, ivert, 
          vertex_normal[0][ivert][iface], vertex_normal[1][ivert][iface],
          vertex_normal[2][ivert][iface] );
        text_num = text_num + 1;
      }
    }

    fprintf ( fileout, "\n" );
    fprintf ( fileout, "Vertex materials:\n" );
    fprintf ( fileout, "\n" );
    text_num = text_num + 3;

    for ( iface = 0; iface < face_num; iface++ ) {
      fprintf ( fileout, "%d", iface );
      for ( ivert = 0; ivert < face_order[iface]; ivert++ ) {
        fprintf ( fileout, " %d", vertex_material[ivert][iface] );
      }
      fprintf ( fileout, "\n" );
      text_num = text_num + 1;
    }

    if ( texture_num > 0 ) {

      fprintf ( fileout, "\n" );
      fprintf ( fileout, "Vertex UV texture coordinates:\n" );
      fprintf ( fileout, "\n" );
      text_num = text_num + 3;

      for ( iface = 0; iface < face_num; iface++ ) {
        for ( ivert = 0; ivert < face_order[iface]; ivert++ ) {
          fprintf ( fileout, "%d %d %f %f\n", iface, ivert,
            vertex_tex_uv[0][ivert][iface], vertex_tex_uv[1][ivert][iface] );
          text_num = text_num + 1;
        }
      }
    }
  }
/*
  MATERIALS.
*/
  fprintf ( fileout, "\n" );
  fprintf ( fileout, "%d materials.\n", material_num );
  fprintf ( fileout, "\n" );
  fprintf ( fileout, "Index      Name   R G B A\n" );
  fprintf ( fileout, "\n" );

  text_num = text_num + 5;

  for ( imat = 0; imat < material_num; imat++ ) {
    fprintf ( fileout, "%d %s %f %f %f %f\n", imat, material_name[imat],
      material_rgba[0][imat], material_rgba[1][imat], material_rgba[2][imat],
      material_rgba[3][imat] );
    text_num = text_num + 1;
  }
/*
  TEXTURES.
*/
  fprintf ( fileout, "\n" );
  fprintf ( fileout, "%d textures.\n", texture_num );
  text_num = text_num + 2;

  if ( texture_num > 0 ) {
    fprintf ( fileout, "\n" );
    fprintf ( fileout, "Index  Name\n" );
    fprintf ( fileout, "\n" );
    for ( i = 0; i < texture_num; i++ ) {
      fprintf ( fileout, "%d %s\n", i, texture_name[i] );
    }
    text_num = text_num + 3;
  }
/*
  Report.
*/
  printf ( "\n" );
  printf ( "TXT_WRITE - Wrote %d text lines.\n", text_num );

  return SUCCESS;
}
/**********************************************************************/

int ucd_write ( FILE *fileout )

/**********************************************************************/

/*
  Purpose:

    UCD_WRITE writes graphics data to an AVS UCD file.

  Examples:

    #  cube.ucd created by IVREAD.
    #
    #  Material RGB to hue map:
    #
    #  material    R    G  B   Alpha     Hue
    #
    #    0   0.94  0.70  0.15  1.000   0.116
    #    1   0.24  0.70  0.85  1.000   0.541
    #    2   0.24  0.00  0.85  1.000   0.666
    #
    #  The node data is
    #    node # / material # / RGBA / Hue
    #
    8  6  6  0  0
    0  0.0  0.0  0.0
    1  1.0  0.0  0.0
    2  1.0  1.0  0.0
    3  0.0  1.0  0.0
    4  0.0  0.0  1.0
    5  1.0  0.0  1.0
    6  1.0  1.0  1.0
    7  0.0  1.0  1.0
    0  0  quad  0  1  2  3
    1  0  quad  0  4  5  1
    2  0  quad  1  5  6  2
    3  0  quad  2  6  7  3
    4  0  quad  3  7  4  0
    5  0  quad  4  7  6  5
    3  1 4 1
    material, 0...2
    RGBA, 0-1/0-1/0-1/0-1
    Hue, 0-1
    0  0  0.94  0.70  0.15  1.0  0.116
    1  0  0.94  0.70  0.15  1.0  0.116
    2  0  0.94  0.70  0.15  1.0  0.116
    3  0  0.94  0.70  0.15  1.0  0.116
    4  1  0.24  0.70  0.85  1.0  0.541
    5  1  0.24  0.70  0.85  1.0  0.541
    6  2  0.24  0.24  0.85  0.0  0.666
    7  2  0.24  0.24  0.85  0.0  0.666

  Modified:

    22 May 1999

  Author:

    John Burkardt

*/
{
  float a;
  float b;
  float g;
  float h;
  int i;
  int imat;
  int j;
  int text_num;
  float r;

  text_num = 0;

  fprintf ( fileout, "#  %s created by IVREAD.\n", fileout_name );
  fprintf ( fileout, "#\n" );
  fprintf ( fileout, "#  Material RGB to Hue map:\n" );
  fprintf ( fileout, "#\n" );
  fprintf ( fileout, "#  material    R    G      B     Alpha  Hue\n" );
  fprintf ( fileout, "#\n" );

  text_num = text_num + 6;

  for ( j = 0; j < material_num; j++ ) {
    r = material_rgba[0][j];
    g = material_rgba[1][j];
    b = material_rgba[2][j];
    a = material_rgba[3][j];
    h = rgb_to_hue ( r, g, b );
    fprintf ( fileout, "#  %d %f %f %f %f %f\n", j, r, g, b, a, h );
    text_num = text_num + 1;
  }

  fprintf ( fileout, "#\n" );
  fprintf ( fileout, "#  The node data is\n" );
  fprintf ( fileout, "#    node # / material # / RGBA / Hue\n" );
  fprintf ( fileout, "#\n" );
  text_num = text_num + 4;

  fprintf ( fileout, "%d %d 6 0 0\n", cor3_num, face_num );
  text_num = text_num + 1;

  for ( j = 0; j < cor3_num; j++ ) {
    fprintf ( fileout, "%d %f %f %f\n", j, cor3[0][j], cor3[1][j],
      cor3[2][j] );
    text_num = text_num + 1;
  }
/*
  NOTE:
  UCD only accepts triangles and quadrilaterals, not higher order
  polygons.  We would need to break polygons up to proceed.
*/
  for ( j = 0; j < face_num; j++ ) {

    fprintf ( fileout, "%d %d", j, face_material[j] );

    if ( face_order[j] == 3 ) {
      fprintf ( fileout, " tri" );
    }
    else if ( face_order[j] == 4 ) {
      fprintf ( fileout, " quad" );
    }
    else {
      fprintf ( fileout, " ???" );
    }

    for ( i = 0; i < face_order[j]; i++ ) {
      fprintf ( fileout, "%d", face[i][j] );
    }
    fprintf ( fileout, "\n" );
    text_num = text_num + 1;

  }

  fprintf ( fileout, "3  1  4  1\n" );
  fprintf ( fileout, "material, 0...%d\n", material_num - 1 );
  fprintf ( fileout, "RGBA, 0-1/0-1/0-1/0-1\n" );
  fprintf ( fileout, "Hue, 0-1\n" );
  text_num = text_num + 4;

  for ( j = 0; j < cor3_num; j++ ) {
    imat = cor3_material[j];
    r = material_rgba[0][imat];
    g = material_rgba[1][imat];
    b = material_rgba[2][imat];
    a = material_rgba[3][imat];
    h = rgb_to_hue ( r, g, b );

    fprintf ( fileout, "%d %d %f %f %f %f %f\n", j, imat, r, g, b, a, h );
    text_num = text_num + 1;
  }
/*
  Report.
*/
  printf ( "\n" );
  printf ( "UCD_WRITE - Wrote %d text lines.\n", text_num );

  return SUCCESS;
}
/******************************************************************************/

void vertex_normal_set ( void )

/******************************************************************************/

/*
  Purpose:

    VERTEX_NORMAL_SET recomputes the face vertex normal vectors.

  Modified:

    12 October 1998

  Author:

    John Burkardt
*/
{
  int   i;
  int   i0;
  int   i1;
  int   i2;
  int   iface;
  int   ivert;
  int   jp1;
  int   jp2;
  int   nfix;
  float norm;
  float temp;
  float x0;
  float x1;
  float x2;
  float xc;
  float y0;
  float y1;
  float y2;
  float yc;
  float z0;
  float z1;
  float z2;
  float zc;

  if ( face_num <= 0 ) {
    return;
  }

  nfix = 0;
/*
  Consider each face.
*/
  for ( iface = 0; iface < face_num; iface++ ) {

    for ( ivert = 0; ivert < face_order[iface]; ivert++ ) {

      norm = 0.0;
      for ( i = 0; i < 3; i++ ) {
        temp = vertex_normal[i][ivert][iface];
        norm = norm + temp * temp;
      }
      norm = ( float ) sqrt ( norm );

      if ( norm == 0.0 ) {

        nfix = nfix + 1;

        i0 = face[ivert][iface];
        x0 = cor3[0][i0];
        y0 = cor3[1][i0];
        z0 = cor3[2][i0];

        jp1 = ivert + 1;
        if ( jp1 >= face_order[iface] ) {
          jp1 = jp1 - face_order[iface];
        }
        i1 = face[jp1][iface];
        x1 = cor3[0][i1];
        y1 = cor3[1][i1];
        z1 = cor3[2][i1];

        jp2 = ivert + 2;
        if ( jp2 >= face_order[iface] ) {
          jp2 = jp2 - face_order[iface];
        }
        i2 = face[jp2][iface];
        x2 = cor3[0][i2];
        y2 = cor3[1][i2];
        z2 = cor3[2][i2];

        xc = ( y1 - y0 ) * ( z2 - z0 ) - ( z1 - z0 ) * ( y2 - y0 );
        yc = ( z1 - z0 ) * ( x2 - x0 ) - ( x1 - x0 ) * ( z2 - z0 );
        zc = ( x1 - x0 ) * ( y2 - y0 ) - ( y1 - y0 ) * ( x2 - x0 );

        norm = ( float ) sqrt ( xc * xc + yc * yc + zc * zc );

        if ( norm == 0.0 ) {
          xc = ( float ) 1.0 / sqrt ( 3.0 );
          yc = ( float ) 1.0 / sqrt ( 3.0 );
          zc = ( float ) 1.0 / sqrt ( 3.0 );
        }
        else {
          xc = xc / norm;
          yc = yc / norm;
          zc = zc / norm;
        }

        vertex_normal[0][ivert][iface] = xc;
        vertex_normal[1][ivert][iface] = yc;
        vertex_normal[2][ivert][iface] = zc;

      }
    }
  }

  if ( nfix > 0 ) {
    printf ( "\n" );
    printf ( "VERTEX_NORMAL_SET: Recomputed %d face vertex normals.\n", nfix );
  }

  return;
}
/**********************************************************************/

void vertex_to_face_material ( void )

/**********************************************************************/

/*
  Purpose:

    VERTEX_TO_FACE_MATERIAL extends vertex material definitions to faces.

  Discussion:

    Assuming material indices are defined for all the vertices, this
    routine assigns to each face the material associated with its
    first vertex.

  Modified:

    22 May 1999

  Author:

    John Burkardt
*/
{
  int iface;
  int ivert;

  ivert = 0;
  for ( iface = 0; iface < face_num; iface++ ) {
    face_material[iface] = vertex_material[ivert][iface];
  }

  return;
}
/**********************************************************************/

void vertex_to_node_material ( void )

/**********************************************************************/

/*
  Purpose:

    VERTEX_TO_NODE_MATERIAL extends vertex material definitions to nodes.

  Discussion:

    A NODE is a point in space.
    A VERTEX is a node as used in a particular face.
    One node may be used as a vertex in several faces, or none.
    This routine simply runs through all the vertices, and assigns
    the material of the vertex to the corresponding node.  If a
    node appears as a vertex several times, then the node will
    end up having the material of the vertex that occurs "last".

  Modified:

    22 May 1999

  Author:

    John Burkardt
*/
{
  int iface;
  int ivert;
  int node;

  for ( iface = 0; iface < face_num; iface++ ) {
    for ( ivert = 0; ivert < face_order[iface]; ivert++ ) {
      node = face[ivert][iface];
      cor3_material[node] = vertex_material[ivert][iface];
    }
  }

  return;
}

/******************************************************************************/

int vla_read ( FILE *filein )

/******************************************************************************/

/*
  Purpose:
   
    VLA_READ reads a VLA file.

  Examples:

     set comment cube.vla created by IVREAD
     set comment Original data in cube.iv.
     set comment
     set intensity EXPLICIT
     set parametric NON_PARAMETRIC
     set filecontent LINES
     set filetype NEW
     set depthcue 0
     set defaultdraw stellar
     set coordsys RIGHT
     set author IVREAD
     set site Buhl Planetarium
     set library_id UNKNOWN
     P   8.59816       5.55317      -3.05561       1.00000
     L   8.59816       2.49756      0.000000E+00   1.00000
     L   8.59816       2.49756      -3.05561       1.00000
     L   8.59816       5.55317      -3.05561       1.00000
     P   8.59816       5.55317      0.000000E+00   1.00000
     ...etc...
     L   2.48695       2.49756      -3.05561       1.00000

  Modified:

    23 May 1999

  Author:
 
    John Burkardt
*/
{
  int   i;
  int   icor3;
  int   dup_num;
  char *next;
  int   text_num;
  float r1;
  float r2;
  float r3;
  float temp[3];
  char  token[LINE_MAX_LEN];
  int   width;
/*
  Initialize. 
*/
  dup_num = 0;
  text_num = 0;
/* 
  Read the next line of the file into INPUT. 
*/
  while ( fgets ( input, LINE_MAX_LEN, filein ) != NULL ) {

    text_num = text_num + 1;
/* 
  Advance to the first nonspace character in INPUT.
*/
    for ( next = input; *next != '\0' && isspace(*next); next++ ) {
    }
/* 
  Skip blank lines and comments. 
*/
    if ( *next == '\0' || *next == ';' ) {
      continue;
    }
/* 
  Extract the first word in this line. 
*/
    sscanf ( next, "%s%n", token, &width );
/* 
  Set NEXT to point to just after this token. 
*/
    next = next + width;
/* 
  SET (ignore) 
*/
    if ( leqi ( token, "set" ) == TRUE ) {
    }
/* 
  P (begin a line)
  L (continue a line) 
*/
    else if ( leqi ( token, "P" ) == TRUE || leqi ( token, "L") == TRUE ) {

      if ( leqi ( token, "P" ) == TRUE ) {
        if ( line_num > 0 ) {
          if ( line_num < LINES_MAX ) {
            line_dex[line_num] = -1;
            line_material[line_num] = -1;
            line_num = line_num + 1;
          }
        }
      }

      sscanf ( next, "%e %e %e", &r1, &r2, &r3 );

      temp[0] = r1;
      temp[1] = r2;
      temp[2] = r3;

      if ( cor3_num < 1000 ) {
        icor3 = rcol_find ( cor3, 3, cor3_num, temp );
      }
      else {
        icor3 = -1;
      }

      if ( icor3 == -1 ) {

        icor3 = cor3_num;

        if ( cor3_num < COR3_MAX ) {
          for ( i = 0; i < 3; i++ ) {
            cor3[i][cor3_num] = temp[i];
          }
        }
        cor3_num = cor3_num + 1;
      }
      else {
        dup_num = dup_num + 1;
      }

      if ( line_num < LINES_MAX ) {
        line_dex[line_num] = icor3;
        line_material[line_num] = 0;
        line_num = line_num + 1;
      }
    }
/* 
  Unexpected or unrecognized. 
*/
    else {
      printf ( "\n" );
      printf ( "VLA_READ - Fatal error!\n" );
      printf ( "  Unrecognized first word on line.\n" );
      return ERROR;
    }

  }

  if ( line_num > 0 ) {
    if ( line_num < LINES_MAX ) {
      line_dex[line_num] = -1;
      line_material[line_num] = -1;
      line_num = line_num + 1;
    }
  }

  return SUCCESS;
}
/******************************************************************************/

int vla_write ( FILE *fileout )

/******************************************************************************/

/*
  Purpose:
   
    VLA_WRITE writes internal graphics information to a VLA file.

  Discussion:

    Comments begin with a semicolon in column 1.
    The X, Y, Z coordinates of points begin with a "P" to
    denote the beginning of a line, and "L" to denote the
    continuation of a line.  The fourth entry is intensity, which 
    should be between 0.0 and 1.0.

  Examples:

     set comment cube.vla created by IVREAD
     set comment Original data in cube.iv.
     set comment
     set intensity EXPLICIT
     set parametric NON_PARAMETRIC
     set filecontent LINES
     set filetype NEW
     set depthcue 0
     set defaultdraw stellar
     set coordsys RIGHT
     set author IVREAD
     set site Buhl Planetarium
     set library_id UNKNOWN
     P   8.59816       5.55317      -3.05561       1.00000
     L   8.59816       2.49756      0.000000E+00   1.00000
     L   8.59816       2.49756      -3.05561       1.00000
     L   8.59816       5.55317      -3.05561       1.00000
     P   8.59816       5.55317      0.000000E+00   1.00000
     ...etc...
     L   2.48695       2.49756      -3.05561       1.00000

  Modified:

    22 May 1999

  Author:
 
    John Burkardt
*/
{
  char  c;
  int   iline;
  float intense = 1.0;
  int   k;
  int   text_num;
/* 
  Initialize. 
*/
  text_num = 0;

  fprintf ( fileout, "set comment %s created by IVCON.\n", fileout_name );
  fprintf ( fileout, "set comment Original data in %s.\n", filein_name );
  fprintf ( fileout, "set comment\n" );
  fprintf ( fileout, "set intensity EXPLICIT\n" );
  fprintf ( fileout, "set parametric NON_PARAMETRIC\n" );
  fprintf ( fileout, "set filecontent LINES\n" );
  fprintf ( fileout, "set filetype NEW\n" );
  fprintf ( fileout, "set depthcue 0\n" );
  fprintf ( fileout, "set defaultdraw stellar\n" );
  fprintf ( fileout, "set coordsys RIGHT\n" );
  fprintf ( fileout, "set author IVCON\n" );
  fprintf ( fileout, "set site Buhl Planetarium\n" );
  fprintf ( fileout, "set library_id UNKNOWN\n" );

  text_num = text_num + 13;

  c = 'P';

  for ( iline = 0; iline < line_num; iline++ ) {
    
    k = line_dex[iline];

    if ( k == -1 ) {

      c = 'P';
    }
    else {

      fprintf ( fileout, "%c %f %f %f %f\n", 
        c, cor3[0][k], cor3[1][k], cor3[2][k], intense );

      text_num = text_num + 1;

      c = 'L';
    }
  }
/*
  Report.
*/
  printf ( "\n" );
  printf ( "VLA_WRITE - Wrote %d text lines.\n", text_num );


  return SUCCESS;
}

/**********************************************************************/

int wrl_write ( FILE *fileout )

/**********************************************************************/

/*
  Purpose:

    WRL_WRITE writes graphics data to a WRL file.

  Example:

    #VRML V2.0 utf8

    WorldInfo {
      title "cube.iv."
      string "WRL file generated by IVREAD.
    }

    Group {
      children [

        Shape {

          appearance Appearance {
            material Material {
              diffuseColor   0.0 0.0 0.0
              emissiveColor  0.0 0.0 0.0
              shininess      1.0
            }
          } #end of appearance

          geometry IndexedLineSet {

            coord Coordinate {
              point [
                8.59816       5.55317      -3.05561
                8.59816       2.49756      0.000000E+00
                ...etc...
                2.48695       2.49756      -3.05561
              ]
            }

            coordIndex [
                0     1     2    -1     3     4     5     6     7     8    -
                9    10    -1    11    12    -1    13    14    15    -1    1
              ...etc...
              191    -1
            ]

            colorPerVertex TRUE

            colorIndex [
                0     0     0    -1     2     3     1     1     4     7    -
               10     9    -1     7     7    -1     3     2     2    -1    1
              ...etc...
              180    -1
            ]

          }  #end of geometry

        }  #end of Shape

      ]  #end of children

    }  #end of Group

  Modified:

    23 May 1999

  Author:

    John Burkardt
*/
{
  int icor3;
  int iface;
  int itemp;
  int ivert;
  int j;
  int length;
  int ndx;

  text_num = 0;

  fprintf ( fileout, "#VRML V2.0 utf8\n" );
  fprintf ( fileout, "\n" );
  fprintf ( fileout, "  WorldInfo {\n" );
  fprintf ( fileout, "    title \"%s\"\n", fileout_name );
  fprintf ( fileout, "    info \"WRL file generated by IVREAD.\"\n" );
  fprintf ( fileout, "    info \"Original data in %s\"\n", filein_name );
  fprintf ( fileout, "  }\n" );
  fprintf ( fileout, "\n" );
  fprintf ( fileout, "  Group {\n" );
  fprintf ( fileout, "    children [\n" );
  fprintf ( fileout, "      Shape {\n" );
  fprintf ( fileout, "        appearance Appearance {\n" );
  fprintf ( fileout, "          material Material {\n" );
  fprintf ( fileout, "            diffuseColor   0.0 0.0 0.0\n" );
  fprintf ( fileout, "            emissiveColor  0.0 0.0 0.0\n" );
  fprintf ( fileout, "            shininess      1.0\n" );
  fprintf ( fileout, "          }\n" );
  fprintf ( fileout, "        }\n" );

  text_num = text_num + 18;
/*
  IndexedLineSet
*/
  if ( line_num > 0 ) {

    fprintf ( fileout, "        geometry IndexedLineSet {\n" );
/*
  IndexedLineSet coord
*/
    fprintf ( fileout, "          coord Coordinate {\n" );
    fprintf ( fileout, "            point [\n" );

    text_num = text_num + 3;

    for ( icor3 = 0; icor3 < cor3_num; icor3++ ) {
      fprintf ( fileout, "              %f %f %f\n", cor3[0][icor3],
        cor3[1][icor3], cor3[2][icor3] );
      text_num = text_num + 1;
    }

    fprintf ( fileout, "            ]\n" );
    fprintf ( fileout, "          }\n" );
    text_num = text_num + 2;
/*
  IndexedLineSet coordIndex.
*/
    fprintf ( fileout, "          coordIndex [\n" );

    text_num = text_num + 1;

    length = 0;
    for ( j = 0; j < line_num; j++ ) {
      fprintf ( fileout, "%d ", line_dex[j] );
      length = length + 1;
      if ( line_dex[j] == -1 || length >= 10 || j == line_num - 1 ) {
        fprintf ( fileout, "\n" );
        text_num = text_num + 1;
        length = 0;
      }
    }

    fprintf ( fileout, "          ]\n" );
    text_num = text_num + 1;
/*
  Colors. (materials)
*/
    fprintf ( fileout, "          color Color {\n" );
    fprintf ( fileout, "            color [\n" );
    text_num = text_num + 2;

    for ( j = 0; j < material_num; j++ ) {
      fprintf ( fileout, "              %f %f %f\n", material_rgba[0][j],
        material_rgba[1][j], material_rgba[2][j] );
      text_num = text_num + 1;
    }

    fprintf ( fileout, "            ]\n" );
    fprintf ( fileout, "          }\n" );
    fprintf ( fileout, "          colorPerVertex TRUE\n" );
/*
  IndexedLineset colorIndex
*/
    fprintf ( fileout, "          colorIndex [\n" );

    text_num = text_num + 4;

    length = 0;
    for ( j = 0; j < line_num; j++ ) {
      fprintf ( fileout, "%d ", line_material[j] );
      length = length + 1;
      if ( line_dex[j] == -1 || length >= 10 || j == line_num - 1 ) {
        fprintf ( fileout, "\n" );
        text_num = text_num + 1;
        length = 0;
      }
    }

    fprintf ( fileout, "          ]\n" );
    fprintf ( fileout, "        }\n" );
    text_num = text_num + 2;

  }
/*
  End of IndexedLineSet

  IndexedFaceSet
*/
  if ( face_num > 0 ) {

    fprintf ( fileout, "        geometry IndexedFaceSet {\n" );
/*
  IndexedFaceSet coord
*/
    fprintf ( fileout, "          coord Coordinate {\n" );
    fprintf ( fileout, "            point [\n" );

    text_num = text_num + 3;

    for ( icor3 = 0; icor3 < cor3_num; icor3++ ) {
      fprintf ( fileout, "              %f %f %f\n", cor3[0][icor3],
        cor3[1][icor3], cor3[2][icor3] );

      text_num = text_num + 1;
    }

    fprintf ( fileout, "            ]\n" );
    fprintf ( fileout, "          }\n" );
/*
  IndexedFaceSet coordIndex.
*/
    fprintf ( fileout, "          coordIndex [\n" );

    text_num = text_num + 3;

    length = 0;

    for ( iface = 0; iface < face_num; iface++ ) {

      for ( ivert = 0; ivert <= face_order[iface]; ivert++ ) {

        if ( ivert <= face_order[iface] ) {
          itemp = face[ivert][iface];
        }
        else {
          itemp = 0;
        }

        fprintf ( fileout, "%d ", itemp );
        length = length + 1;

        if ( itemp == -1 || length >= 10 ||
          ( iface == face_num - 1 && ivert == face_order[iface]  ) ) {
          fprintf ( fileout, "\n" );
          text_num = text_num + 1;
          length = 0;
        }

      }

    }

    fprintf ( fileout, "          ]\n" );
    text_num = text_num + 1;
/*
  IndexedFaceset colorIndex
*/
    fprintf ( fileout, "          colorIndex [\n" );
    text_num = text_num + 1;

    length = 0;
    ndx = 0;

    for ( iface = 0; iface < face_num; iface++ ) {

      for ( ivert = 0; ivert <= face_order[iface]; ivert++ ) {

        if ( ivert <= face_order[iface] ) {
          itemp = vertex_material[ivert][iface];
          ndx = ndx + 1;
        }
        else {
          itemp = 0;
        }

        fprintf ( fileout, "%d ", itemp );
        length = length + 1;

        if ( itemp == -1 || length >= 10 ||
          ( iface == face_num - 1 && ivert == face_order[iface] )  ) {

          fprintf ( fileout, "\n" );
          text_num = text_num + 1;
          length = 0;

        }

      }

    }

    fprintf ( fileout, "          ]\n" );
    fprintf ( fileout, "        }\n" );
    text_num = text_num + 2;

  }
/*
  End of IndexedFaceSet

  End of:
    Shape
  children
    Group
*/
  fprintf ( fileout, "      }\n" );
  fprintf ( fileout, "    ]\n" );
  fprintf ( fileout, "  }\n" );

  text_num = text_num + 3;
/*
  Report.
*/
  printf ( "\n" );
  printf ( "WRL_WRITE - Wrote %d text lines.\n", text_num );

  return SUCCESS;
}
/******************************************************************************/

int xgl_write ( FILE *fileout )

/******************************************************************************/

/*
  Purpose:
   
    XGL_WRITE writes an XGL file.

  Discussion:

    Two corrections to the routine were pointed out by
    Mike Phillips, msphil@widowmaker.com, on 17 September 2001,
    and are gratefully acknowledged.

  Example:

    <WORLD>
     
      <BACKGROUND>
        <BACKCOLOR> 0.1, 0.1, 0.1 </BACKCOLOR>
      </BACKGROUND>
     
      <LIGHTING>
        <AMBIENT> 0.2, 0.1, 0.1 </AMBIENT>
        <DIRECTIONALLIGHT>
          <DIFFUSE> 0.1, 0.2, 0.1 </DIFFUSE>
          <DIRECTION> 0, 0, 100 </DIRECTION>
          <SPECULAR> 0.1, 0.1, 0.2 </SPECULAR>
        </DIRECTIONALLIGHT>
      </LIGHTING>
     
      <MESH ID = "0">
     
        <P ID="0"> -0.5, -0.5, 1 </P>
        <P ID="1"> 0.5, -0.5, 1 </P>
        <P ID="2"> 0.5, 0.5, 1 </P>
        <P ID="3"> -0.5, 0.5, 1 </P>
        <P ID="4"> 0.5, -0.5, 0 </P>
        <P ID="5"> -0.5, -0.5, 0 </P>
        <P ID="6"> -0.5, 0.5, 0 </P>
        <P ID="7"> 0.5, 0.5, 0 </P>
     
        <N ID="0"> -0.408248, -0.408248, 0.816497 </N>
        <N ID="1"> 0.666667, -0.666667, 0.333333 </N>
        <N ID="2"> 0.408248, 0.408248, 0.816497 </N>
        <N ID="3"> -0.666667, 0.666667, 0.333333 </N>
        <N ID="4"> 0.408248, -0.408248, -0.816497 </N>
        <N ID="5"> -0.666667, -0.666667, -0.333333 </N>
        <N ID="6"> -0.408248, 0.408248, -0.816497 </N>
        <N ID="7"> 0.666667, 0.666667, -0.333333 </N>
     
        <MAT ID="0">
          <ALPHA> 0.9 </ALPHA>
          <AMB> 0.1, 0.1, 0.1 </AMB>
          <DIFF> 0.2, 0.1, 0.1 </DIFF>
          <EMISS> 0.1, 0.2, 0.1 </EMISS>
          <SHINE> 0.8 </SHINE>
          <SPEC> 0.1, 0.1, 0.2 </SPEC>
        </MAT>
     
        <F>
          <MATREF> 0 </MATREF>
          <FV1><PREF> 0 </PREF><NREF> 0 </NREF></FV1>
          <FV2><PREF> 1 </PREF><NREF> 1 </NREF></FV2>
          <FV3><PREF> 2 </PREF><NREF> 2 </NREF></FV3>
        </F>
        <F>
          <MATREF> 0 </MATREF>
          <FV1><PREF> 0 </PREF><NREF> 0 </NREF></FV1>
          <FV2><PREF> 2 </PREF><NREF> 2 </NREF></FV2>
          <FV3><PREF> 3 </PREF><NREF> 3 </NREF></FV3>
        </F>
        <F>
          <MATREF> 0 </MATREF>
          <FV1><PREF> 4 </PREF><NREF> 4 </NREF></FV1>
          <FV2><PREF> 5 </PREF><NREF> 5 </NREF></FV2>
          <FV3><PREF> 6 </PREF><NREF> 6 </NREF></FV3>
        </F>
        <F>
          <MATREF> 0 </MATREF>
          <FV1><PREF> 4 </PREF><NREF> 4 </NREF></FV1>
          <FV2><PREF> 6 </PREF><NREF> 6 </NREF></FV2>
          <FV3><PREF> 7 </PREF><NREF> 7 </NREF></FV3>
        </F>
        <F>
          <MATREF> 0 </MATREF>
          <FV1><PREF> 5 </PREF><NREF> 5 </NREF></FV1>
          <FV2><PREF> 0 </PREF><NREF> 0 </NREF></FV2>
          <FV3><PREF> 3 </PREF><NREF> 3 </NREF></FV3>
        </F>
        <F>
          <MATREF> 0 </MATREF>
          <FV1><PREF> 5 </PREF><NREF> 5 </NREF></FV1>
          <FV2><PREF> 3 </PREF><NREF> 3 </NREF></FV2>
          <FV3><PREF> 6 </PREF><NREF> 6 </NREF></FV3>
        </F>
        <F>
          <MATREF> 0 </MATREF>
          <FV1><PREF> 1 </PREF><NREF> 1 </NREF></FV1>
          <FV2><PREF> 4 </PREF><NREF> 4 </NREF></FV2>
          <FV3><PREF> 7 </PREF><NREF> 7 </NREF></FV3>
        </F>
        <F>
          <MATREF> 0 </MATREF>
          <FV1><PREF> 1 </PREF><NREF> 1 </NREF></FV1>
          <FV2><PREF> 7 </PREF><NREF> 7 </NREF></FV2>
          <FV3><PREF> 2 </PREF><NREF> 2 </NREF></FV3>
        </F>
        <F>
          <MATREF> 0 </MATREF>
          <FV1><PREF> 5 </PREF><NREF> 5 </NREF></FV1>
          <FV2><PREF> 4 </PREF><NREF> 4 </NREF></FV2>
          <FV3><PREF> 1 </PREF><NREF> 1 </NREF></FV3>
        </F>
        <F>
          <MATREF> 0 </MATREF>
          <FV1><PREF> 5 </PREF><NREF> 5 </NREF></FV1>
          <FV2><PREF> 1 </PREF><NREF> 1 </NREF></FV2>
          <FV3><PREF> 0 </PREF><NREF> 0 </NREF></FV3>
        </F>
        <F>
          <MATREF> 0 </MATREF>
          <FV1><PREF> 3 </PREF><NREF> 3 </NREF></FV1>
          <FV2><PREF> 2 </PREF><NREF> 2 </NREF></FV2>
          <FV3><PREF> 7 </PREF><NREF> 7 </NREF></FV3>
        </F>
        <F>
          <MATREF> 0 </MATREF>
          <FV1><PREF> 3 </PREF><NREF> 3 </NREF></FV1>
          <FV2><PREF> 7 </PREF><NREF> 7 </NREF></FV2>
          <FV3><PREF> 6 </PREF><NREF> 6 </NREF></FV3>
        </F>
      </MESH>
     
      <OBJECT>
        <TRANSFORM>
          <FORWARD> 0, 0, 0 </FORWARD>
          <POSITION> 0, 0, 0 </POSITION>
          <SCALE> 1, 1, 1 </SCALE>
          <UP> 1, 1, 1 </UP>
        </TRANSFORM>
        <MESHREF> 0 </MESHREF>
      </OBJECT>
     
    </WORLD>

  Reference:

    XGL specification at http://www.xglspec.org/

  Modified:

    17 September 2001

  Author:
 
    John Burkardt
*/
{
  int iface;
  int ivert;
  int j;
  float light_ambient_rgb[3];
  float light_diffuse_rgb[3];
  float light_direction[3];
  float light_specular_rgb[3];
  int material;
  float material_alpha;
  float material_amb_rgb[3];
  float material_diff_rgb[3];
  float material_emiss_rgb[3];
  float material_shine;
  float material_spec_rgb[3];
  int mesh;
  int mesh_num = 1;
  int object;
  float transform_forward[3];
  float transform_position[3];
  float transform_scale[3];
  float transform_up[3];
/*
  Make up some placeholder values for now.
*/
  light_ambient_rgb[0] = 0.2;
  light_ambient_rgb[1] = 0.1;
  light_ambient_rgb[2] = 0.1;

  light_diffuse_rgb[0] = 0.1;
  light_diffuse_rgb[1] = 0.2;
  light_diffuse_rgb[2] = 0.1;

  light_direction[0] =   0.0;
  light_direction[1] =   0.0;
  light_direction[2] = 100.0;

  light_specular_rgb[0] = 0.1;
  light_specular_rgb[1] = 0.1;
  light_specular_rgb[2] = 0.2;

  material_alpha = 0.9;

  material_amb_rgb[0] = 0.1;
  material_amb_rgb[1] = 0.1;
  material_amb_rgb[2] = 0.1;

  material_diff_rgb[0] = 0.2;
  material_diff_rgb[1] = 0.1;
  material_diff_rgb[2] = 0.1;

  material_emiss_rgb[0] = 0.1;
  material_emiss_rgb[1] = 0.2;
  material_emiss_rgb[2] = 0.1;

  material_shine = 0.8;

  material_spec_rgb[0] = 0.1;
  material_spec_rgb[1] = 0.1;
  material_spec_rgb[2] = 0.2;

  transform_forward[0] = 0.0;
  transform_forward[1] = 0.0;
  transform_forward[2] = 0.0;

  transform_position[0] = 0.0;
  transform_position[1] = 0.0;
  transform_position[2] = 0.0;

  transform_scale[0] = 1.0;
  transform_scale[1] = 1.0;
  transform_scale[2] = 1.0;

  transform_up[0] = 1.0;
  transform_up[1] = 1.0;
  transform_up[2] = 1.0;

  object_num = 1;

  text_num = 0;

  fprintf ( fileout, "<WORLD>\n" );
  fprintf ( fileout, "\n" );

  text_num = text_num + 2;

  fprintf ( fileout, "  <BACKGROUND>\n" );
  fprintf ( fileout, "    <BACKCOLOR> %f, %f, %f </BACKCOLOR>\n", 
    background_rgb[0], background_rgb[1], background_rgb[2] );
  fprintf ( fileout, "  </BACKGROUND>\n" );
  fprintf ( fileout, "\n" );
  fprintf ( fileout, "  <LIGHTING>\n" );
  fprintf ( fileout, "    <AMBIENT> %f, %f, %f </AMBIENT>\n",
    light_ambient_rgb[0], light_ambient_rgb[1], light_ambient_rgb[2] );
  fprintf ( fileout, "    <DIRECTIONALLIGHT>\n" );
  fprintf ( fileout, "      <DIFFUSE> %f, %f, %f </DIFFUSE>\n",
    light_diffuse_rgb[0], light_diffuse_rgb[1], light_diffuse_rgb[2] );
  fprintf ( fileout, "      <DIRECTION> %f, %f, %f </DIRECTION>\n",
    light_direction[0], light_direction[1], light_direction[2] );
  fprintf ( fileout, "      <SPECULAR> %f, %f, %f </SPECULAR>\n",
    light_specular_rgb[0], light_specular_rgb[1], light_specular_rgb[2] );
  fprintf ( fileout, "    </DIRECTIONALLIGHT>\n" );
  fprintf ( fileout, "  </LIGHTING>\n" );

  text_num = text_num + 12;

  for ( mesh = 0; mesh < mesh_num; mesh++ ) {

    fprintf ( fileout, "\n" );
    fprintf ( fileout, "  <MESH ID = \"%d\">\n", mesh );
    fprintf ( fileout, "\n" );
    text_num = text_num + 3;

    for ( j = 0; j < cor3_num; j++ ) {
      fprintf ( fileout, "    <P ID=\"%d\"> %f, %f, %f </P>\n", j,
        cor3[0][j], cor3[1][j], cor3[2][j] );
      text_num = text_num + 1;
    }

    fprintf ( fileout, "\n" );
    text_num = text_num + 1;
    for ( j = 0; j < cor3_num; j++ ) {
      fprintf ( fileout, "    <N ID=\"%d\"> %f, %f, %f </N>\n", j,
        cor3_normal[0][j], cor3_normal[1][j], cor3_normal[2][j] );
      text_num = text_num + 1;
    }

    for ( material = 0; material < material_num; material++ ) {
      fprintf ( fileout, "\n" );
      fprintf ( fileout, "    <MAT ID=\"%d\">\n", material );
      fprintf ( fileout, "      <ALPHA> %f </ALPHA>\n", material_alpha );
      fprintf ( fileout, "      <AMB> %f, %f, %f </AMB>\n",
        material_amb_rgb[0], material_amb_rgb[1], material_amb_rgb[2] );
      fprintf ( fileout, "      <DIFF> %f, %f, %f </DIFF>\n",
        material_diff_rgb[0], material_diff_rgb[1], material_diff_rgb[2] );
      fprintf ( fileout, "      <EMISS> %f, %f, %f </EMISS>\n",
        material_emiss_rgb[0], material_emiss_rgb[1], material_emiss_rgb[2] );
      fprintf ( fileout, "      <SHINE> %f </SHINE>\n", material_shine );
      fprintf ( fileout, "      <SPEC> %f, %f, %f </SPEC>\n",
        material_spec_rgb[0], material_spec_rgb[1], material_spec_rgb[2] );
      fprintf ( fileout, "    </MAT>\n" );
      text_num = text_num + 9;
    }

    fprintf ( fileout, "\n" );
    text_num = text_num + 1;

    for ( iface = 0; iface < face_num; iface++ ) {
      fprintf ( fileout, "    <F>\n" );
      fprintf ( fileout, "      <MATREF> %d </MATREF>\n", face_material[iface] );
      text_num = text_num + 2;
      for ( ivert = 0; ivert < face_order[iface]; ivert++ ) {
        fprintf ( fileout, 
          "      <FV%d><PREF> %d </PREF><NREF> %d </NREF></FV%d>\n",
          ivert+1, face[ivert][iface], face[ivert][iface], ivert+1 );
        text_num = text_num + 1;
      }
      fprintf ( fileout, "    </F>\n" );
      text_num = text_num + 1;
    }

    fprintf ( fileout, "  </MESH>\n" );
    text_num = text_num + 1;

  }

  fprintf ( fileout, "\n" );
  text_num = text_num + 1;

  for ( object = 0; object < object_num; object++ ) {

    fprintf ( fileout, "  <OBJECT>\n" );
    fprintf ( fileout, "    <TRANSFORM>\n" );
    fprintf ( fileout, "      <FORWARD> %f, %f, %f </FORWARD>\n",
      transform_forward[0], transform_forward[1], transform_forward[2] );
    fprintf ( fileout, "      <POSITION> %f, %f, %f </POSITION>\n",
      transform_position[0], transform_position[1], transform_position[2] );
    fprintf ( fileout, "'      <SCALE> %f, %f, %f </SCALE>\n",
      transform_scale[0], transform_scale[1], transform_scale[2] );
    fprintf ( fileout, "      <UP> %f, %f, %f </UP>\n",
      transform_up[0], transform_up[1], transform_up[2] );
    fprintf ( fileout, "    </TRANSFORM>\n" );
    mesh = 0;
    fprintf ( fileout, "    <MESHREF> %d </MESHREF>\n", mesh );
    fprintf ( fileout, "  </OBJECT>\n" );
    text_num = text_num + 9;

  }

  fprintf ( fileout, "\n" );
  fprintf ( fileout, "</WORLD>\n" );
  text_num = text_num + 2;

/*
  Report.
*/
  printf ( "\n" );
  printf ( "XGL_WRITE - Wrote %d text lines.\n", text_num );

  return SUCCESS;
}