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draw.c
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draw.c
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#include <stdio.h>
#include <stdlib.h>
#include <math.h>
#include "ml6.h"
#include "display.h"
#include "draw.h"
#include "matrix.h"
/*======== void add_polygon() ==========
Inputs: struct matrix *surfaces
double x0
double y0
double z0
double x1
double y1
double z1
double x2
double y2
double z2
Returns:
Adds the vertices (x0, y0, z0), (x1, y1, z1)
and (x2, y2, z2) to the polygon matrix. They
define a single triangle surface.
04/16/13 13:05:59
jdyrlandweaver
====================*/
void add_polygon( struct matrix *polygons,
double x0, double y0, double z0,
double x1, double y1, double z1,
double x2, double y2, double z2 ) {
add_point(polygons, x0, y0, z0);
add_point(polygons, x1, y1, z1);
add_point(polygons, x2, y2, z2);
}
/*======== void draw_polygons() ==========
Inputs: struct matrix *polygons
screen s
color c
Returns:
Goes through polygons 3 points at a time, drawing
lines connecting each points to create bounding
triangles
04/16/13 13:13:27
jdyrlandweaver
====================*/
void draw_polygons( struct matrix *polygons, screen s, color c ) {
int i;
double vx = 0;
double vy = 0;
double vz = -1;
double ax, ay, az, bx, by, bz, nx, ny, nz;
// for (i = 0; i < polygons->lastcol; i += 3) { // Possible seg fault
for (i=0;i<polygons->lastcol-2;i+=3){
ax = polygons->m[0][i+1] - polygons->m[0][i];
ay = polygons->m[1][i+1] - polygons->m[1][i];
az = polygons->m[2][i+1] - polygons->m[2][i];
bx = polygons->m[0][i+2] - polygons->m[0][i];
by = polygons->m[1][i+2] - polygons->m[1][i];
bz = polygons->m[2][i+2] - polygons->m[2][i];
nx = ay * bz - az * by;
ny = az * bx - ax * bz;
nz = ax * by - ay * bx;
if ((nx * vx + ny * vy + nz * vz)<0){
draw_line(polygons->m[0][i],polygons->m[1][i],
polygons->m[0][i+1],polygons->m[1][i+1],
s,c);
draw_line(polygons->m[0][i+1],polygons->m[1][i+1],
polygons->m[0][i+2],polygons->m[1][i+2],
s,c);
draw_line(polygons->m[0][i+2],polygons->m[1][i+2],
polygons->m[0][i],polygons->m[1][i],
s,c);
}
/* draw_line(polygons->m[0][i], polygons->m[1][i], polygons->m[0][i + 1], polygons->m[1][i + 1], s, c);
draw_line(polygons->m[0][i + 1], polygons->m[1][i + 1], polygons->m[0][i + 2], polygons->m[1][i + 2], s, c);
draw_line(polygons->m[0][i + 2], polygons->m[1][i + 2], polygons->m[0][i], polygons->m[1][i], s, c);*/
}
}
/*======== void add_sphere() ==========
Inputs: struct matrix * points
double cx
double cy
double r
double step
Returns:
adds all the points for a sphere with center
(cx, cy) and radius r.
should call generate_sphere to create the
necessary points
jdyrlandweaver
====================*/
void add_sphere( struct matrix * points,
double cx, double cy, double r,
int step ) {
struct matrix * temp;
int lat, longt;
int index;
double x, y, z;
int num_steps;
num_steps = MAX_STEPS / step;
temp = new_matrix( 4, num_steps * num_steps );
//generate the points on the sphere
generate_sphere( temp, cx, cy, r, step );
int latStop, longStop, latStart, longStart;
latStart = 0;
latStop = num_steps;
longStart = 0;
longStop = num_steps;
index = 0;
/*print_points(temp);
printf("\n\n\n\n\n\n\n\n");
*/
int tmp = 0;
for ( lat = latStart; lat < latStop; lat++ ) {
if (tmp == (num_steps - 1)) {
for ( longt = longStart; longt < longStop; longt++ ) { // 1 is longStop
// index = lat * (num_steps+1) + longt;
if (index % num_steps == (num_steps - 1)) {
add_polygon( points,
temp->m[0][index],
temp->m[1][index],
temp->m[2][index],
temp->m[0][index % num_steps],
temp->m[1][index % num_steps],
temp->m[2][index % num_steps],
temp->m[0][0],
temp->m[1][0],
temp->m[2][0]
);
add_polygon( points,
temp->m[0][index],
temp->m[1][index],
temp->m[2][index],
temp->m[0][0],
temp->m[1][0],
temp->m[2][0],
temp->m[0][index - (num_steps - 1)],
temp->m[1][index - (num_steps - 1)],
temp->m[2][index - (num_steps - 1)]
);
}
else {
add_polygon( points,
temp->m[0][index],
temp->m[1][index],
temp->m[2][index],
temp->m[0][(index % num_steps)],
temp->m[1][(index % num_steps)],
temp->m[2][(index % num_steps)],
temp->m[0][(index % num_steps) + 1],
temp->m[1][(index % num_steps) + 1],
temp->m[2][(index % num_steps) + 1]
);
add_polygon( points,
temp->m[0][index],
temp->m[1][index],
temp->m[2][index],
temp->m[0][(index % num_steps) + 1],
temp->m[1][(index % num_steps) + 1],
temp->m[2][(index % num_steps) + 1],
temp->m[0][index + 1],
temp->m[1][index + 1],
temp->m[2][index + 1]
);
}
index += 1;
}
}
else{
for ( longt = longStart; longt < longStop; longt++ ) { // 1 is longStop
// printf("index: %d\n", index);
// index = lat * (num_steps+1) + longt;
if (index % num_steps == (num_steps - 1)) {
/* printf("Special case\n");
printf("connection indices: %f, %f, %f\n", index, index + num_steps, index + 1);
printf("connection indices: %f, %f, %f\n", index, index + 1, index - (num_steps - 1));
printf("index point: %f, %f, %f\n", temp->m[0][index] , temp->m[1][index], temp->m[2][index]);
printf("index + num_steps point, %f, %f, %f\n", temp->m[0][index + num_steps], temp->m[1][index + num_steps], temp->m[2][index + num_steps]);
printf("NEXT\n");*/
add_polygon( points,
temp->m[0][index],
temp->m[1][index],
temp->m[2][index],
temp->m[0][index + num_steps],
temp->m[1][index + num_steps],
temp->m[2][index + num_steps],
temp->m[0][index + 1],
temp->m[1][index + 1],
temp->m[2][index + 1]
);
add_polygon( points,
temp->m[0][index],
temp->m[1][index],
temp->m[2][index],
temp->m[0][index + 1],
temp->m[1][index + 1],
temp->m[2][index + 1],
temp->m[0][index - (num_steps - 1)],
temp->m[1][index - (num_steps - 1)],
temp->m[2][index - (num_steps - 1)]
);
}
else {
/* printf("index point: %f, %f, %f\n", temp->m[0][index], temp->m[1][index], temp->m[2][index]);
printf("index + num_steps point, %f, %f, %f\n", temp->m[0][index + num_steps], temp->m[1][index + num_steps], temp->m[2][index + num_steps]);
printf("connection indices: %f, %f, %f\n", index, index + num_steps, index + num_steps + 1);
printf("connection indices: %f, %f, %f\n", index, index + num_steps + 1, index + 1);*/
// printf("NEXT\n");
add_polygon( points,
temp->m[0][index],
temp->m[1][index],
temp->m[2][index],
temp->m[0][index + num_steps],
temp->m[1][index + num_steps],
temp->m[2][index + num_steps],
temp->m[0][index + num_steps + 1],
temp->m[1][index + num_steps + 1],
temp->m[2][index + num_steps + 1]
);
add_polygon( points,
temp->m[0][index],
temp->m[1][index],
temp->m[2][index],
temp->m[0][index + num_steps + 1],
temp->m[1][index + num_steps + 1],
temp->m[2][index + num_steps + 1],
temp->m[0][index + 1],
temp->m[1][index + 1],
temp->m[2][index + 1]
);
}
index += 1;
}
}
tmp += 1;
}
/* add_edge( points,
temp->m[0][index],
temp->m[1][index],
temp->m[2][index],
temp->m[0][index + 1],
temp->m[1][index + 1],
temp->m[2][index] );
*/
//end points only
/* printf("\n\n\n\n");
print_matrix(points);*/
free_matrix(temp);
}
/*======== void generate_sphere() ==========
Inputs: struct matrix * points
double cx
double cy
double r
double step
Returns:
Generates all the points along the surface of a
sphere with center (cx, cy) and radius r
Adds these points to the matrix parameter
03/22/12 11:30:26
jdyrlandweaver
====================*/
void generate_sphere( struct matrix * points,
double cx, double cy, double r,
int step ) {
int circle, rotation;
double x, y, z, circ, rot;
int rotStart = step * 0;
int rotStop = MAX_STEPS;
int circStart = step * 0;
int circStop = MAX_STEPS;
for ( rotation = rotStart; rotation < rotStop; rotation += step ) {
rot = (double)rotation / MAX_STEPS;
for ( circle = circStart; circle < circStop; circle+= step ) {
circ = (double)circle / MAX_STEPS;
x = r * cos( 2 * M_PI * circ ) + cx;
y = r * sin( 2 * M_PI * circ ) * cos( 2 * M_PI * rot ) + cy;
z = r * sin( 2 * M_PI * circ ) * sin( 2 * M_PI * rot );
add_point( points, x, y, z);
}
}
}
/*======== void add_torus() ==========
Inputs: struct matrix * points
double cx
double cy
double r1
double r2
double step
Returns:
adds all the points required to make a torus
with center (cx, cy) and radii r1 and r2.
should call generate_torus to create the
necessary points
03/22/12 13:34:03
jdyrlandweaver
====================*/
void add_torus( struct matrix * points,
double cx, double cy, double r1, double r2,
int step ) {
struct matrix * temp;
int lat, longt;
int index;
int num_steps;
num_steps = MAX_STEPS / step;
temp = new_matrix( 4, num_steps * num_steps );
//generate the points on the torus
generate_torus( temp, cx, cy, r1, r2, step );
int latStop, longStop, latStart, longStart;
latStart = 0;
longStart = 0;
latStop = num_steps;
longStop = num_steps;
index = 0;
int tmp = 0;
for ( lat = latStart; lat < latStop; lat++ ) {
if (tmp == (num_steps - 1)) {
for ( longt = longStart; longt < longStop; longt++ ) { // 1 is longStop
// index = lat * (num_steps+1) + longt;
if (index % num_steps == (num_steps - 1)) {
add_polygon( points,
temp->m[0][index],
temp->m[1][index],
temp->m[2][index],
temp->m[0][(index % num_steps)],
temp->m[1][(index % num_steps)],
temp->m[2][(index % num_steps)],
temp->m[0][0],
temp->m[1][0],
temp->m[2][0]
);
add_polygon( points,
temp->m[0][index],
temp->m[1][index],
temp->m[2][index],
temp->m[0][0],
temp->m[1][0],
temp->m[2][0],
temp->m[0][index - (num_steps - 1)],
temp->m[1][index - (num_steps - 1)],
temp->m[2][index - (num_steps - 1)]
);
}
else {
add_polygon( points,
temp->m[0][index],
temp->m[1][index],
temp->m[2][index],
temp->m[0][(index % num_steps)],
temp->m[1][(index % num_steps)],
temp->m[2][(index % num_steps)],
temp->m[0][(index % num_steps) + 1],
temp->m[1][(index % num_steps) + 1],
temp->m[2][(index % num_steps) + 1]
);
add_polygon( points,
temp->m[0][index],
temp->m[1][index],
temp->m[2][index],
temp->m[0][(index % num_steps) + 1],
temp->m[1][(index % num_steps) + 1],
temp->m[2][(index % num_steps) + 1],
temp->m[0][index + 1],
temp->m[1][index + 1],
temp->m[2][index + 1]
);
}
index += 1;
}
}
else {
for ( longt = longStart; longt < longStop; longt++ ) { // 1 is longStop
// index = lat * (num_steps+1) + longt;
if (index % num_steps == (num_steps - 1)) {
add_polygon( points,
temp->m[0][index],
temp->m[1][index],
temp->m[2][index],
temp->m[0][index + num_steps],
temp->m[1][index + num_steps],
temp->m[2][index + num_steps],
temp->m[0][index + 1],
temp->m[1][index + 1],
temp->m[2][index + 1]
);
add_polygon( points,
temp->m[0][index],
temp->m[1][index],
temp->m[2][index],
temp->m[0][index + 1],
temp->m[1][index + 1],
temp->m[2][index + 1],
temp->m[0][index - (num_steps - 1)],
temp->m[1][index - (num_steps - 1)],
temp->m[2][index - (num_steps - 1)]
);
}
else {
add_polygon( points,
temp->m[0][index],
temp->m[1][index],
temp->m[2][index],
temp->m[0][index + num_steps],
temp->m[1][index + num_steps],
temp->m[2][index + num_steps],
temp->m[0][index + num_steps + 1],
temp->m[1][index + num_steps + 1],
temp->m[2][index + num_steps + 1]
);
add_polygon( points,
temp->m[0][index],
temp->m[1][index],
temp->m[2][index],
temp->m[0][index + num_steps + 1],
temp->m[1][index + num_steps + 1],
temp->m[2][index + num_steps + 1],
temp->m[0][index + 1],
temp->m[1][index + 1],
temp->m[2][index + 1]
);
}
index += 1;
}
}
tmp += 1;
}
/* index = lat * num_steps + longt;
add_edge( points, temp->m[0][index],
temp->m[1][index],
temp->m[2][index],
temp->m[0][index] + 1,
temp->m[1][index] + 1,
temp->m[2][index] );
*/
//end points only
}
/*======== void generate_torus() ==========
Inputs: struct matrix * points
double cx
double cy
double r
double step
Returns:
Generates all the points along the surface of a
tarus with center (cx, cy) and radii r1 and r2
Adds these points to the matrix parameter
03/22/12 11:30:26
jdyrlandweaver
====================*/
void generate_torus( struct matrix * points,
double cx, double cy, double r1, double r2,
int step ) {
double x, y, z, circ, rot;
int circle, rotation;
double rotStart = step * 0;
double rotStop = MAX_STEPS;
double circStart = step * 0;
double circStop = MAX_STEPS;
for ( rotation = rotStart; rotation < rotStop; rotation += step ) {
rot = (double)rotation / MAX_STEPS;
for ( circle = circStart; circle < circStop; circle+= step ) {
circ = (double)circle / MAX_STEPS;
x = cos( 2 * M_PI * rot ) *
( r1 * cos( 2 * M_PI * circ ) + r2 ) + cx;
y = r1 * sin( 2 * M_PI * circ ) + cy;
z = sin( 2 * M_PI * rot ) *
( r1 * cos( 2 * M_PI * circ ) + r2 );
add_point( points, x, y, z );
}
}
}
/*======== void add_box() ==========
Inputs: struct matrix * points
double x
double y
double z
double width
double height
double depth
Returns:
add the points for a rectagular prism whose
upper-left corner is (x, y, z) with width,
height and depth dimensions.
jdyrlandweaver
====================*/
void add_box( struct matrix * points,
double x, double y, double z,
double width, double height, double depth ) {
double x2, y2, z2;
x2 = x + width;
y2 = y - height;
z2 = z - depth;
add_polygon( points,
x, y2, z,
x2, y, z,
x, y, z
);
add_polygon( points,
x, y2, z,
x2, y2, z,
x2, y, z
);
add_polygon( points,
x2, y2, z,
x2, y, z2,
x2, y, z
);
add_polygon( points,
x2, y, z2,
x2, y2, z,
x2, y2, z2
);
add_polygon( points,
x2, y, z2,
x2, y2, z2,
x, y, z2
);
add_polygon( points,
x2, y2, z2,
x, y2, z2,
x, y, z2
);
add_polygon( points,
x, y2, z,
x, y, z,
x, y, z2
);
add_polygon( points,
x, y2, z2,
x, y2, z,
x, y, z2
);
add_polygon( points,
x2, y, z,
x, y, z2,
x, y, z
);
add_polygon( points,
x2, y, z,
x2, y, z2,
x, y, z2
);
add_polygon( points,
x2, y2, z,
x, y2, z2,
x2, y2, z2
);
add_polygon( points,
x, y2, z2,
x2, y2, z,
x, y2, z
);
/*
add_edge( points,
x, y, z,
x, y, z );
add_edge( points,
x, y2, z,
x, y2, z );
add_edge( points,
x2, y, z,
x2, y, z );
add_edge( points,
x2, y2, z,
x2, y2, z );
add_edge( points,
x, y, z2,
x, y, z2 );
add_edge( points,
x, y2, z2,
x, y2, z2 );
add_edge( points,
x2, y, z2,
x2, y, z2 );
add_edge( points,
x2, y2, z2,
x2, y2, z2 );
*/
}
/*======== void add_circle() ==========
Inputs: struct matrix * points
double cx
double cy
double y
double step
Returns:
03/16/12 19:53:52
jdyrlandweaver
====================*/
void add_circle( struct matrix * points,
double cx, double cy,
double r, double step ) {
double x0, y0, x, y, t;
x0 = cx + r;
y0 = cy;
for ( t = step; t <= 1; t+= step ) {
x = r * cos( 2 * M_PI * t ) + cx;
y = r * sin( 2 * M_PI * t ) + cy;
add_edge( points, x0, y0, 0, x, y, 0 );
x0 = x;
y0 = y;
}
add_edge( points, x0, y0, 0, cx + r, cy, 0 );
}
/*======== void add_curve() ==========
Inputs: struct matrix *points
double x0
double y0
double x1
double y1
double x2
double y2
double x3
double y3
double step
int type
Returns:
Adds the curve bounded by the 4 points passsed as parameters
of type specified in type (see matrix.h for curve type constants)
to the matrix points
03/16/12 15:24:25
jdyrlandweaver
====================*/
void add_curve( struct matrix *points,
double x0, double y0,
double x1, double y1,
double x2, double y2,
double x3, double y3,
double step, int type ) {
double x, y, t;
struct matrix * xcoefs;
struct matrix * ycoefs;
//generate the coeficients
if ( type == BEZIER_MODE ) {
ycoefs = generate_curve_coefs(y0, y1, y2, y3, BEZIER_MODE);
xcoefs = generate_curve_coefs(x0, x1, x2, x3, BEZIER_MODE);
}
else {
xcoefs = generate_curve_coefs(x0, x1, x2, x3, HERMITE_MODE);
ycoefs = generate_curve_coefs(y0, y1, y2, y3, HERMITE_MODE);
}
/*
printf("a = %lf b = %lf c = %lf d = %lf\n", xcoefs->m[0][0],
xcoefs->m[1][0], xcoefs->m[2][0], xcoefs->m[3][0]);
*/
for (t=step; t <= 1; t+= step) {
x = xcoefs->m[0][0] * t * t * t + xcoefs->m[1][0] * t * t
+ xcoefs->m[2][0] * t + xcoefs->m[3][0];
y = ycoefs->m[0][0] * t * t * t + ycoefs->m[1][0] * t * t
+ ycoefs->m[2][0] * t + ycoefs->m[3][0];
add_edge(points, x0, y0, 0, x, y, 0);
x0 = x;
y0 = y;
}
free_matrix(xcoefs);
free_matrix(ycoefs);
}
/*======== void add_point() ==========
Inputs: struct matrix * points
int x
int y
int z
Returns:
adds point (x, y, z) to points and increment points.lastcol
if points is full, should call grow on points
====================*/
void add_point( struct matrix * points, double x, double y, double z) {
if ( points->lastcol == points->cols )
grow_matrix( points, points->lastcol + 100 );
points->m[0][points->lastcol] = x;
points->m[1][points->lastcol] = y;
points->m[2][points->lastcol] = z;
points->m[3][points->lastcol] = 1;
points->lastcol++;
}
/*======== void add_edge() ==========
Inputs: struct matrix * points
int x0, int y0, int z0, int x1, int y1, int z1
Returns:
add the line connecting (x0, y0, z0) to (x1, y1, z1) to points
should use add_point
====================*/
void add_edge( struct matrix * points,
double x0, double y0, double z0,
double x1, double y1, double z1) {
add_point( points, x0, y0, z0 );
add_point( points, x1, y1, z1 );
}
/*======== void draw_lines() ==========
Inputs: struct matrix * points
screen s
color c
Returns:
Go through points 2 at a time and call draw_line to add that line
to the screen
====================*/
void draw_lines( struct matrix * points, screen s, color c) {
int i;
if ( points->lastcol < 2 ) {
printf("Need at least 2 points to draw a line!\n");
return;
}
for ( i = 0; i < points->lastcol - 1; i+=2 ) {
draw_line( points->m[0][i], points->m[1][i],
points->m[0][i+1], points->m[1][i+1], s, c);
//FOR DEMONSTRATION PURPOSES ONLY
//draw extra pixels so points can actually be seen
/*
draw_line( points->m[0][i]+1, points->m[1][i],
points->m[0][i+1]+1, points->m[1][i+1], s, c);
draw_line( points->m[0][i], points->m[1][i]+1,
points->m[0][i+1], points->m[1][i+1]+1, s, c);
draw_line( points->m[0][i]-1, points->m[1][i],
points->m[0][i+1]-1, points->m[1][i+1], s, c);
draw_line( points->m[0][i], points->m[1][i]-1,
points->m[0][i+1], points->m[1][i+1]-1, s, c);
draw_line( points->m[0][i]+1, points->m[1][i]+1,
points->m[0][i+1]+1, points->m[1][i+1]+1, s, c);
draw_line( points->m[0][i]-1, points->m[1][i]+1,
points->m[0][i+1]-1, points->m[1][i+1]+1, s, c);
draw_line( points->m[0][i]-1, points->m[1][i]-1,
points->m[0][i+1]-1, points->m[1][i+1]-1, s, c);
draw_line( points->m[0][i]+1, points->m[1][i]-1,
points->m[0][i+1]+1, points->m[1][i+1]-1, s, c);
*/
}
}
void draw_line(int x0, int y0, int x1, int y1, screen s, color c) {
int x, y, d, dx, dy;
x = x0;
y = y0;
//swap points so we're always draing left to right
if ( x0 > x1 ) {
x = x1;
y = y1;
x1 = x0;
y1 = y0;
}
//need to know dx and dy for this version
dx = (x1 - x) * 2;
dy = (y1 - y) * 2;
//positive slope: Octants 1, 2 (5 and 6)
if ( dy > 0 ) {
//slope < 1: Octant 1 (5)
if ( dx > dy ) {
d = dy - ( dx / 2 );
while ( x <= x1 ) {
plot(s, c, x, y);
if ( d < 0 ) {
x = x + 1;
d = d + dy;
}
else {
x = x + 1;
y = y + 1;
d = d + dy - dx;
}
}
}
//slope > 1: Octant 2 (6)
else {
d = ( dy / 2 ) - dx;
while ( y <= y1 ) {
plot(s, c, x, y );
if ( d > 0 ) {
y = y + 1;
d = d - dx;
}
else {
y = y + 1;
x = x + 1;
d = d + dy - dx;
}
}
}
}
//negative slope: Octants 7, 8 (3 and 4)
else {
//slope > -1: Octant 8 (4)
if ( dx > abs(dy) ) {
d = dy + ( dx / 2 );
while ( x <= x1 ) {
plot(s, c, x, y);
if ( d > 0 ) {
x = x + 1;
d = d + dy;
}
else {
x = x + 1;
y = y - 1;
d = d + dy + dx;
}
}
}
//slope < -1: Octant 7 (3)
else {
d = (dy / 2) + dx;
while ( y >= y1 ) {
plot(s, c, x, y );
if ( d < 0 ) {
y = y - 1;
d = d + dx;
}
else {
y = y - 1;
x = x + 1;
d = d + dy + dx;
}
}
}
}
}