bitmap.c

/*         ______   ___    ___
 *        /\  _  \ /\_ \  /\_ \
 *        \ \ \L\ \\//\ \ \//\ \      __     __   _ __   ___
 *         \ \  __ \ \ \ \  \ \ \   /'__`\ /'_ `\/\`'__\/ __`\
 *          \ \ \/\ \ \_\ \_ \_\ \_/\  __//\ \L\ \ \ \//\ \L\ \
 *           \ \_\ \_\/\____\/\____\ \____\ \____ \ \_\\ \____/
 *            \/_/\/_/\/____/\/____/\/____/\/___L\ \/_/ \/___/
 *                                           /\____/
 *                                           \_/__/
 *
 *      New bitmap routines.
 *
 *      By Elias Pschernig and Trent Gamblin.
 *
 *      See readme.txt for copyright information.
 */

/* Title: Bitmap routines
 */


#include <string.h>
#include "allegro5/allegro.h"
#include "allegro5/internal/aintern.h"
#include "allegro5/internal/aintern_bitmap.h"
#include "allegro5/internal/aintern_display.h"
#include "allegro5/internal/aintern_pixels.h"
#include "allegro5/internal/aintern_shader.h"
#include "allegro5/internal/aintern_system.h"

ALLEGRO_DEBUG_CHANNEL("bitmap")


/* Creates a memory bitmap.
 */
static ALLEGRO_BITMAP *create_memory_bitmap(ALLEGRO_DISPLAY *current_display,
   int w, int h, int format, int flags)
{
   ALLEGRO_BITMAP *bitmap;
   int pitch;

   if (_al_pixel_format_is_video_only(format)) {
      /* Can't have a video-only memory bitmap... */
      return NULL;
   }

   format = _al_get_real_pixel_format(current_display, format);

   bitmap = al_calloc(1, sizeof *bitmap);

   pitch = w * al_get_pixel_size(format);

   bitmap->vt = NULL;
   bitmap->_format = format;

   /* If this is really a video bitmap, we add it to the list of to
    * be converted bitmaps.
    */
   bitmap->_flags = flags | ALLEGRO_MEMORY_BITMAP;
   bitmap->_flags &= ~ALLEGRO_VIDEO_BITMAP;
   bitmap->w = w;
   bitmap->h = h;
   bitmap->pitch = pitch;
   bitmap->_display = NULL;
   bitmap->locked = false;
   bitmap->cl = bitmap->ct = 0;
   bitmap->cr_excl = w;
   bitmap->cb_excl = h;
   al_identity_transform(&bitmap->transform);
   al_identity_transform(&bitmap->inverse_transform);
   bitmap->inverse_transform_dirty = false;
   al_identity_transform(&bitmap->proj_transform);
   al_orthographic_transform(&bitmap->proj_transform, 0, 0, -1.0, w, h, 1.0);
   bitmap->parent = NULL;
   bitmap->xofs = bitmap->yofs = 0;
   bitmap->memory = al_malloc(pitch * h);
   bitmap->use_bitmap_blender = false;
   bitmap->blender.blend_color = al_map_rgba(0, 0, 0, 0);
   al_get_new_bitmap_wrap(&bitmap->_wrap_u, &bitmap->_wrap_v);
   
   _al_register_convert_bitmap(bitmap);
   return bitmap;
}



static void destroy_memory_bitmap(ALLEGRO_BITMAP *bmp)
{
   _al_unregister_convert_bitmap(bmp);

   if (bmp->memory)
      al_free(bmp->memory);
   al_free(bmp);
}



ALLEGRO_BITMAP *_al_create_bitmap_params(ALLEGRO_DISPLAY *current_display,
   int w, int h, int format, int flags, int depth, int samples)
{
   ALLEGRO_SYSTEM *system = al_get_system_driver();
   ALLEGRO_BITMAP *bitmap;
   ALLEGRO_BITMAP **back;
   bool result;
   /* Reject bitmaps with negative dimensions.
    * Also reject bitmaps where a calculation pixel_size*w*h would overflow
    * int.  Supporting such bitmaps would require a lot more work.
    * Overflow calc based on https://stackoverflow.com/a/1514309/231929
    */
   if (w < 0 || h < 0 || (h > 0 && (int64_t) w > (INT_MAX/4) / (int64_t) h)) {
      ALLEGRO_WARN("Rejecting %dx%d bitmap\n", w, h);
      return NULL;
   }

   if ((flags & ALLEGRO_MEMORY_BITMAP) ||
         !current_display ||
         !current_display->vt ||
         current_display->vt->create_bitmap == NULL ||
         _al_vector_size(&system->displays) < 1)
   {
      if (flags & ALLEGRO_VIDEO_BITMAP)
         return NULL;

      return create_memory_bitmap(current_display, w, h, format, flags);
   }

   /* Else it's a display bitmap */

   bitmap = current_display->vt->create_bitmap(current_display, w, h,
      format, flags);
   if (!bitmap) {
      ALLEGRO_ERROR("failed to create display bitmap\n");
      return NULL;
   }

   bitmap->_display = current_display;
   bitmap->w = w;
   bitmap->h = h;
   bitmap->locked = false;
   bitmap->cl = 0;
   bitmap->ct = 0;
   bitmap->cr_excl = w;
   bitmap->cb_excl = h;
   al_identity_transform(&bitmap->transform);
   al_identity_transform(&bitmap->inverse_transform);
   bitmap->inverse_transform_dirty = false;
   al_identity_transform(&bitmap->proj_transform);
   al_orthographic_transform(&bitmap->proj_transform, 0, 0, -1.0, w, h, 1.0);
   bitmap->parent = NULL;
   bitmap->xofs = 0;
   bitmap->yofs = 0;
   bitmap->_flags |= ALLEGRO_VIDEO_BITMAP;
   bitmap->dirty = !(bitmap->_flags & ALLEGRO_NO_PRESERVE_TEXTURE);
   bitmap->_depth = depth;
   bitmap->_samples = samples;
   bitmap->use_bitmap_blender = false;
   bitmap->blender.blend_color = al_map_rgba(0, 0, 0, 0);
   al_get_new_bitmap_wrap(&bitmap->_wrap_u, &bitmap->_wrap_v);

   /* The display driver should have set the bitmap->memory field if
    * appropriate; video bitmaps may leave it NULL.
    */

   ASSERT(bitmap->pitch >= w * al_get_pixel_size(bitmap->_format));
   result = bitmap->vt->upload_bitmap(bitmap);

   if (!result) {
      al_destroy_bitmap(bitmap);
      if (flags & ALLEGRO_VIDEO_BITMAP)
         return NULL;
      /* With ALLEGRO_CONVERT_BITMAP, just use a memory bitmap instead if
      * video failed.
      */
      return create_memory_bitmap(current_display, w, h, format, flags);
   }
   
   /* We keep a list of bitmaps depending on the current display so that we can
    * convert them to memory bimaps when the display is destroyed. */
   back = _al_vector_alloc_back(&current_display->bitmaps);
   *back = bitmap;

   return bitmap;
}


/* Function: al_create_bitmap
 */
ALLEGRO_BITMAP *al_create_bitmap(int w, int h)
{
   ALLEGRO_BITMAP *bitmap;

   bitmap = _al_create_bitmap_params(al_get_current_display(), w, h,
      al_get_new_bitmap_format(), al_get_new_bitmap_flags(),
      al_get_new_bitmap_depth(), al_get_new_bitmap_samples());
   if (bitmap) {
      bitmap->dtor_item = _al_register_destructor(_al_dtor_list, "bitmap", bitmap,
         (void (*)(void *))al_destroy_bitmap);
   }

   return bitmap;
}


/* Function: al_destroy_bitmap
 */
void al_destroy_bitmap(ALLEGRO_BITMAP *bitmap)
{
   if (!bitmap) {
      return;
   }

   /* As a convenience, implicitly untarget the bitmap on the calling thread
    * before it is destroyed, but maintain the current display.
    */
   if (bitmap == al_get_target_bitmap()) {
      ALLEGRO_DISPLAY *display = al_get_current_display();
      if (display)
         al_set_target_bitmap(al_get_backbuffer(display));
      else
         al_set_target_bitmap(NULL);
   }

   _al_set_bitmap_shader_field(bitmap, NULL);

   _al_unregister_destructor(_al_dtor_list, bitmap->dtor_item);

   if (!al_is_sub_bitmap(bitmap)) {
      ALLEGRO_DISPLAY* disp = _al_get_bitmap_display(bitmap);
      if (al_get_bitmap_flags(bitmap) & ALLEGRO_MEMORY_BITMAP) {
         destroy_memory_bitmap(bitmap);
         return;
      }

      /* Else it's a display bitmap */

      if (bitmap->locked)
         al_unlock_bitmap(bitmap);

      if (bitmap->vt)
         bitmap->vt->destroy_bitmap(bitmap);

      if (disp)
         _al_vector_find_and_delete(&disp->bitmaps, &bitmap);

      if (bitmap->memory)
         al_free(bitmap->memory);
   }

   al_free(bitmap);
}


/* Function: al_convert_mask_to_alpha
 */
void al_convert_mask_to_alpha(ALLEGRO_BITMAP *bitmap, ALLEGRO_COLOR mask_color)
{
   ALLEGRO_LOCKED_REGION *lr;
   int x, y;
   ALLEGRO_COLOR pixel;
   ALLEGRO_COLOR alpha_pixel;
   ALLEGRO_STATE state;

   if (!(lr = al_lock_bitmap(bitmap, ALLEGRO_PIXEL_FORMAT_ANY, 0))) {
      ALLEGRO_ERROR("Couldn't lock bitmap.");
      return;
   }

   al_store_state(&state, ALLEGRO_STATE_TARGET_BITMAP);
   al_set_target_bitmap(bitmap);

   alpha_pixel = al_map_rgba(0, 0, 0, 0);

   for (y = 0; y < bitmap->h; y++) {
      for (x = 0; x < bitmap->w; x++) {
         pixel = al_get_pixel(bitmap, x, y);
         if (memcmp(&pixel, &mask_color, sizeof(ALLEGRO_COLOR)) == 0) {
            al_put_pixel(x, y, alpha_pixel);
         }
      }
   }

   al_unlock_bitmap(bitmap);

   al_restore_state(&state);
}



/* Function: al_get_bitmap_width
 */
int al_get_bitmap_width(ALLEGRO_BITMAP *bitmap)
{
   return bitmap->w;
}



/* Function: al_get_bitmap_height
 */
int al_get_bitmap_height(ALLEGRO_BITMAP *bitmap)
{
   return bitmap->h;
}



/* Function: al_get_bitmap_format
 */
int al_get_bitmap_format(ALLEGRO_BITMAP *bitmap)
{
   if (bitmap->parent)
      return bitmap->parent->_format;
   else
      return bitmap->_format;
}


int _al_get_bitmap_memory_format(ALLEGRO_BITMAP *bitmap)
{
   if (bitmap->parent)
      return bitmap->parent->_memory_format;
   else
      return bitmap->_memory_format;
}



/* Function: al_get_bitmap_flags
 */
int al_get_bitmap_flags(ALLEGRO_BITMAP *bitmap)
{
   if (bitmap->parent)
      return bitmap->parent->_flags;
   else
      return bitmap->_flags;
}


ALLEGRO_DISPLAY *_al_get_bitmap_display(ALLEGRO_BITMAP *bitmap)
{
   if (bitmap->parent)
      return bitmap->parent->_display;
   else
      return bitmap->_display;
}


/* Function: al_get_bitmap_depth
 */
int al_get_bitmap_depth(ALLEGRO_BITMAP *bitmap)
{
   if (bitmap->parent)
      return bitmap->parent->_depth;
   else
      return bitmap->_depth;
}


/* Function: al_get_bitmap_samples
 */
int al_get_bitmap_samples(ALLEGRO_BITMAP *bitmap)
{
   if (bitmap->parent)
      return bitmap->parent->_samples;
   else
      return bitmap->_samples;
}

/* Function: al_get_bitmap_blend_color
 */
ALLEGRO_COLOR al_get_bitmap_blend_color(void)
{
   ALLEGRO_BITMAP *bitmap = al_get_target_bitmap();
   ALLEGRO_BLENDER *b;

   ASSERT(bitmap);

   if (!bitmap->use_bitmap_blender) {
      /* If no bitmap blender set, use TLS */
      return al_get_blend_color();
   }
   
   b = &bitmap->blender;
   return b->blend_color;
}

/* Function: al_get_bitmap_blender
 */
void al_get_bitmap_blender(int *op, int *src, int *dst)
{
   al_get_separate_bitmap_blender(op, src, dst, NULL, NULL, NULL);
}

/* Function: al_get_separate_bitmap_blender
 */
void al_get_separate_bitmap_blender(int *op, int *src, int *dst, int *alpha_op, int *alpha_src, int *alpha_dst)
{
   ALLEGRO_BITMAP *bitmap = al_get_target_bitmap();
   ALLEGRO_BLENDER *b;

   ASSERT(bitmap);

   if (!bitmap->use_bitmap_blender) {
      /* If no bitmap blender set, use TLS */
      al_get_separate_blender(op, src, dst, alpha_op, alpha_src, alpha_dst);
      return;
   }

   b = &bitmap->blender;

   if (op)
      *op = b->blend_op;

   if (src)
      *src = b->blend_source;

   if (dst)
      *dst = b->blend_dest;

   if (alpha_op)
      *alpha_op = b->blend_alpha_op;

   if (alpha_src)
      *alpha_src = b->blend_alpha_source;

   if (alpha_dst)
      *alpha_dst = b->blend_alpha_dest;
}

/* Function: al_set_bitmap_blend_color
 */
void al_set_bitmap_blend_color(ALLEGRO_COLOR col)
{
   ALLEGRO_BITMAP *bitmap = al_get_target_bitmap();
   ALLEGRO_BLENDER *b;

   ASSERT(bitmap);

   b = &bitmap->blender;
   b->blend_color = col;
}

/* Function: al_set_bitmap_blender
 */
void al_set_bitmap_blender(int op, int src, int dest)
{
   ALLEGRO_BITMAP *bitmap = al_get_target_bitmap();

   ASSERT(bitmap);

   al_set_separate_bitmap_blender(op, src, dest, op, src, dest);
}

/* Function: al_set_separate_bitmap_blender
 */
void al_set_separate_bitmap_blender(int op, int src, int dst, int alpha_op, int alpha_src, int alpha_dst)
{
   ALLEGRO_BITMAP *bitmap = al_get_target_bitmap();
   ALLEGRO_BLENDER *b;

   ASSERT(bitmap);

   bitmap->use_bitmap_blender = true;
   b = &bitmap->blender;
   b->blend_op = op;
   b->blend_source = src;
   b->blend_dest = dst;
   b->blend_alpha_op = alpha_op;
   b->blend_alpha_source = alpha_src;
   b->blend_alpha_dest = alpha_dst;
}

/* Function: al_reset_bitmap_blender
 */
void al_reset_bitmap_blender(void)
{
   ALLEGRO_BITMAP *bitmap = al_get_target_bitmap();

   ASSERT(bitmap);

   bitmap->use_bitmap_blender = false;
   bitmap->blender.blend_color = al_map_rgba(0, 0, 0, 0);
}

/* Function: al_set_clipping_rectangle
 */
void al_set_clipping_rectangle(int x, int y, int width, int height)
{
   ALLEGRO_BITMAP *bitmap = al_get_target_bitmap();

   ASSERT(bitmap);

   if (x < 0) {
      width += x;
      x = 0;
   }
   if (y < 0) {
      height += y;
      y = 0;
   }
   if (x + width > bitmap->w) {
      width = bitmap->w - x;
   }
   if (y + height > bitmap->h) {
      height = bitmap->h - y;
   }
   if (width < 0) {
      width = 0;
   }
   if (height < 0) {
      height = 0;
   }

   bitmap->cl = x;
   bitmap->ct = y;
   bitmap->cr_excl = x + width;
   bitmap->cb_excl = y + height;

   if (bitmap->vt && bitmap->vt->update_clipping_rectangle) {
      bitmap->vt->update_clipping_rectangle(bitmap);
   }
}



/* Function: al_reset_clipping_rectangle
 */
void al_reset_clipping_rectangle(void)
{
   ALLEGRO_BITMAP *bitmap = al_get_target_bitmap();

   if (bitmap) {
      int w = al_get_bitmap_width(bitmap);
      int h = al_get_bitmap_height(bitmap);
      al_set_clipping_rectangle(0, 0, w, h);
   }
}



/* Function: al_get_clipping_rectangle
 */
void al_get_clipping_rectangle(int *x, int *y, int *w, int *h)
{
   ALLEGRO_BITMAP *bitmap = al_get_target_bitmap();

   ASSERT(bitmap);

   if (x) *x = bitmap->cl;
   if (y) *y = bitmap->ct;
   if (w) *w = bitmap->cr_excl - bitmap->cl;
   if (h) *h = bitmap->cb_excl - bitmap->ct;
}



/* Function: al_create_sub_bitmap
 */
ALLEGRO_BITMAP *al_create_sub_bitmap(ALLEGRO_BITMAP *parent,
   int x, int y, int w, int h)
{
   ALLEGRO_BITMAP *bitmap;

   if (parent->parent) {
      x += parent->xofs;
      y += parent->yofs;
      parent = parent->parent;
   }
   
   bitmap = al_calloc(1, sizeof *bitmap);
   bitmap->vt = parent->vt;

   /* Sub-bitmap inherits these from the parent.
    * Leave these unchanged so they can be detected if improperly accessed
    * directly. */
   bitmap->_format = 0;
   bitmap->_flags = 0;
   bitmap->_display = (ALLEGRO_DISPLAY*)0x1;
   bitmap->_wrap_u = 0;
   bitmap->_wrap_v = 0;

   bitmap->w = w;
   bitmap->h = h;
   bitmap->locked = false;
   bitmap->cl = bitmap->ct = 0;
   bitmap->cr_excl = w;
   bitmap->cb_excl = h;
   al_identity_transform(&bitmap->transform);
   al_identity_transform(&bitmap->inverse_transform);
   bitmap->inverse_transform_dirty = false;
   al_identity_transform(&bitmap->proj_transform);
   al_orthographic_transform(&bitmap->proj_transform, 0, 0, -1.0, w, h, 1.0);
   bitmap->shader = NULL;
   bitmap->parent = parent;
   bitmap->xofs = x;
   bitmap->yofs = y;
   bitmap->memory = NULL;

   bitmap->dtor_item = _al_register_destructor(_al_dtor_list, "sub_bitmap", bitmap,
      (void (*)(void *))al_destroy_bitmap);

   return bitmap;
}


/* Function: al_reparent_bitmap
 */
void al_reparent_bitmap(ALLEGRO_BITMAP *bitmap, ALLEGRO_BITMAP *parent,
   int x, int y, int w, int h)
{
   ASSERT(bitmap->parent);
   /* Re-parenting a non-sub-bitmap makes no sense, so in release mode
    * just ignore it. */
   if (!bitmap->parent)
      return;

   if (parent->parent) {
      x += parent->xofs;
      y += parent->yofs;
      parent = parent->parent;
   }

   bitmap->parent = parent;
   bitmap->xofs = x;
   bitmap->yofs = y;
   bitmap->w = w;
   bitmap->h = h;
}


/* Function: al_is_sub_bitmap
 */
bool al_is_sub_bitmap(ALLEGRO_BITMAP *bitmap)
{
   return (bitmap->parent != NULL);
}


/* Function: al_get_parent_bitmap
 */
ALLEGRO_BITMAP *al_get_parent_bitmap(ALLEGRO_BITMAP *bitmap)
{
   ASSERT(bitmap);
   return bitmap->parent;
}


/* Function: al_get_bitmap_x
 */
int al_get_bitmap_x(ALLEGRO_BITMAP *bitmap)
{
   ASSERT(bitmap);
   return bitmap->xofs;
}


/* Function: al_get_bitmap_y
 */
int al_get_bitmap_y(ALLEGRO_BITMAP *bitmap)
{
   ASSERT(bitmap);
   return bitmap->yofs;
}


static bool transfer_bitmap_data(ALLEGRO_BITMAP *src, ALLEGRO_BITMAP *dst)
{
   ALLEGRO_LOCKED_REGION *dst_region;
   ALLEGRO_LOCKED_REGION *src_region;
   int src_format = al_get_bitmap_format(src);
   int dst_format = al_get_bitmap_format(dst);
   bool src_compressed = _al_pixel_format_is_compressed(src_format);
   bool dst_compressed = _al_pixel_format_is_compressed(dst_format);
   int copy_w = src->w;
   int copy_h = src->h;

   if (src_compressed && dst_compressed && src_format == dst_format) {
      int block_width = al_get_pixel_block_width(src_format);
      int block_height = al_get_pixel_block_height(src_format);
      if (!(src_region = al_lock_bitmap_blocked(src, ALLEGRO_LOCK_READONLY)))
         return false;

      if (!(dst_region = al_lock_bitmap_blocked(dst, ALLEGRO_LOCK_WRITEONLY))) {
         al_unlock_bitmap(src);
         return false;
      }
      copy_w = _al_get_least_multiple(copy_w, block_width);
      copy_h = _al_get_least_multiple(copy_h, block_height);
      ALLEGRO_DEBUG("Taking fast clone path.\n");
   }
   else {
      int lock_format = ALLEGRO_PIXEL_FORMAT_ANY;
      /* Go through a non-compressed intermediate */
      if (src_compressed && !dst_compressed) {
         lock_format = dst_format;
      }
      else if (!src_compressed && dst_compressed) {
         lock_format = src_format;
      }

      if (!(src_region = al_lock_bitmap(src, lock_format, ALLEGRO_LOCK_READONLY)))
         return false;

      if (!(dst_region = al_lock_bitmap(dst, lock_format, ALLEGRO_LOCK_WRITEONLY))) {
         al_unlock_bitmap(src);
         return false;
      }
   }

   _al_convert_bitmap_data(
      src_region->data, src_region->format, src_region->pitch,
      dst_region->data, dst_region->format, dst_region->pitch,
      0, 0, 0, 0, copy_w, copy_h);

   al_unlock_bitmap(src);
   al_unlock_bitmap(dst);

   return true;
}


void _al_copy_bitmap_data(
   const void *src, int src_pitch, void *dst, int dst_pitch,
   int sx, int sy, int dx, int dy, int width, int height,
   int format)
{
   int block_width = al_get_pixel_block_width(format);
   int block_height = al_get_pixel_block_height(format);
   int block_size = al_get_pixel_block_size(format);
   const char *src_ptr = src;
   char *dst_ptr = dst;
   int y;

   ASSERT(src);
   ASSERT(dst);
   ASSERT(_al_pixel_format_is_real(format));
   ASSERT(width % block_width == 0);
   ASSERT(height % block_height == 0);
   ASSERT(sx % block_width == 0);
   ASSERT(sy % block_height == 0);
   ASSERT(dx % block_width == 0);
   ASSERT(dy % block_height == 0);

   sx /= block_width;
   sy /= block_height;
   dx /= block_width;
   dy /= block_height;
   width /= block_width;
   height /= block_height;

   if ((src_ptr == dst_ptr) && (src_pitch == dst_pitch)) {
      return;
   }

   src_ptr += sy * src_pitch + sx * block_size;
   dst_ptr += dy * dst_pitch + dx * block_size;

   for (y = 0; y < height; y++) {
      memcpy(dst_ptr, src_ptr, width * block_size);
      src_ptr += src_pitch;
      dst_ptr += dst_pitch;
   }
}

void _al_convert_bitmap_data(
   const void *src, int src_format, int src_pitch,
   void *dst, int dst_format, int dst_pitch,
   int sx, int sy, int dx, int dy, int width, int height)
{
   ASSERT(src);
   ASSERT(dst);
   ASSERT(_al_pixel_format_is_real(dst_format));

   /* Use memcpy if no conversion is needed. */
   if (src_format == dst_format) {
      _al_copy_bitmap_data(src, src_pitch, dst, dst_pitch, sx, sy,
         dx, dy, width, height, src_format);
      return;
   }

   /* Video-only formats don't have conversion functions, so they should have
    * been taken care of before reaching this location. */
   ASSERT(!_al_pixel_format_is_video_only(src_format));
   ASSERT(!_al_pixel_format_is_video_only(dst_format));

   (_al_convert_funcs[src_format][dst_format])(src, src_pitch,
      dst, dst_pitch, sx, sy, dx, dy, width, height);
}


/* Function: al_clone_bitmap
 */
ALLEGRO_BITMAP *al_clone_bitmap(ALLEGRO_BITMAP *bitmap)
{
   ALLEGRO_BITMAP *clone;
   ASSERT(bitmap);

   clone = al_create_bitmap(bitmap->w, bitmap->h);
   if (!clone)
      return NULL;
   if (!transfer_bitmap_data(bitmap, clone)) {
      al_destroy_bitmap(clone);
      return NULL;
   }
   return clone;
}


/* Function: al_backup_dirty_bitmap
 */
void al_backup_dirty_bitmap(ALLEGRO_BITMAP *bitmap)
{
   if (bitmap->vt && bitmap->vt->backup_dirty_bitmap)
      bitmap->vt->backup_dirty_bitmap(bitmap);
}


void _al_get_bitmap_wrap(ALLEGRO_BITMAP *bitmap, ALLEGRO_BITMAP_WRAP *wrap_u, ALLEGRO_BITMAP_WRAP *wrap_v)
{
   ASSERT(bitmap);
   ASSERT(wrap_u);
   ASSERT(wrap_v);

   if (bitmap->parent) {
      bitmap = bitmap->parent;
   }

   *wrap_u = bitmap->_wrap_u;
   *wrap_v = bitmap->_wrap_v;
}

/* vim: set ts=8 sts=3 sw=3 et: */