EXTERN_ENV
void Render(long my_node) /* assumes direction is +Z */
{
if (my_node == ROOT) {
Observer_Transform_Light_Vector();
Compute_Observer_Transformed_Highlight_Vector();
}
Ray_Trace(my_node);
}
void RayTraceUtil()
{
int xp, yp;
float xv, yv, dx, dy, dz;
float u, v;
/* Generate a ray for each pixel in the desired image. */
printf("Ray tracing...\n");
for (xp=0; xp<xmax_pixel; xp++)
{
u = (float)xp/xmax_pixel;
for (yp=0; yp<ymax_pixel; yp++)
{
v = (float)yp/ymax_pixel;
/* Compute the corresponding view port coordinates. */
xv = VXL + xp * xinterval;
yv = VYB + yp * yinterval;
/* Compute the direction of the current ray from the "From" point to the
current position on the image. */
dx = ax*xv*tanv2 + bx*yv*tanv2 + cx;
dy = ay*xv*tanv2 + by*yv*tanv2 + cy;
dz = az*xv*tanv2 + bz*yv*tanv2 + cz;
rgb rgb_color = Ray_Trace(0,dx,dy,dz,from,1);
/* Save the computed color intensity to the image buffer. */
texture_R[xp + xmax_pixel * yp] = rgb_color.r;
texture_G[xp + xmax_pixel * yp] = rgb_color.g;
texture_B[xp + xmax_pixel * yp] = rgb_color.b;
}
}
/* Write the image to the output file. */
printf("Writing to image...\n");
fwrite(&xmax_pixel, sizeof(int), 1, outpfile);
fwrite(&ymax_pixel, sizeof(int), 1, outpfile);
fwrite(texture_R, sizeof(float), xmax_pixel*ymax_pixel, outpfile);
fwrite(texture_G, sizeof(float), xmax_pixel*ymax_pixel, outpfile);
fwrite(texture_B, sizeof(float), xmax_pixel*ymax_pixel, outpfile);
fclose(outpfile);
}
rgb Ray_Trace(int obj_num,float dx, float dy,float dz, points from, int depth)
{
int shadow_flag;
int texture, buf_ptr = 0;
int num_image = 1;
float nx, ny, nz;
float t_min, t1, t2, ipx = 0, ipy = 0, ipz = 0;
float rlx, rly, rlz, rfx,rfy,rfz;
rgb rgb_color;
/* Check if the current ray intercepts spheres */
t_min = 999.0;
//obj_num = 0;
texture = 0;
for(int i = 1; i <= NUM_SPHERES; i++)
{
Check_Sphere(from.x, from.y, from.z, dx, dy, dz, c[i-1][0],
c[i-1][1], c[i-1][2], c[i-1][3], &t1, &t2);
if (t1>=0.00001) {
t_min = t1;
obj_num = i;
Compute_Intersection(from.x, from.y, from.z,
dx, dy, dz, t1, &ipx, &ipy, &ipz);
}
if (t2>=0.00001 && t2<t_min) {
t_min = t2;
obj_num = i;
Compute_Intersection(from.x, from.y, from.z,
dx, dy, dz, t2, &ipx, &ipy, &ipz);
}
}
/* Check if the current ray intercepts planes. */
for(int i = 1; i <= NUM_PLANES; i++)
{
Check_Plane(from.x, from.y, from.z, dx, dy, dz, p[i-1][0], p[i-1][1], p[i-1][2], p[i-1][3], &t1);
if (t1 >= 0.00001 && t1<t_min) {
/* Check if the intersection point is inside the min/max values. */
Compute_Intersection(from.x, from.y, from.z,
dx, dy, dz, t1, &ipx, &ipy, &ipz);
if (ipx >= pminmax[i-1][0][0] && ipx <= pminmax[i-1][0][1] &&
ipy >= pminmax[i-1][1][0] && ipy <= pminmax[i-1][1][1] &&
ipz >= pminmax[i-1][2][0] && ipz <= pminmax[i-1][2][1] ) {
t_min = t1;
obj_num = i+NUM_SPHERES;
}
}
}
int grain;
float u,v,w,t,value,x;
/* Compute the intensity to use at the current pixel. */
switch (obj_num) {
/* The current ray does not intersect any of the objects. */
case 0 :rgb_color.r = 0.1;
rgb_color.g = 0.1;
rgb_color.b = 0.1;
break;
/* The current ray intercept sphere #1. */
case 1 :
nx = ipx - c[0][0];
ny = ipy - c[0][1];
nz = ipz - c[0][2];
Normalize(&nx, &ny, &nz);
shadow_flag = 0;
shadow_flag = Check_Shadow(ipx, ipy, ipz, obj_num);
texture = 0;
rgb_color = Compute_Color(shadow_flag, ipx, ipy, ipz, nx, ny, nz, ia, ka_S[0], kd_S[0], ks_S[0], ns_S[0], krg_S[0], ktg_S[0], 1);
break;
/* The current ray intercepts sphere #2. */
case 2 :
nx = ipx - c[1][0];
ny = ipy - c[1][1];
nz = ipz - c[1][2];
Normalize(&nx, &ny, &nz);
shadow_flag = 0;
shadow_flag = Check_Shadow(ipx, ipy, ipz, obj_num);
texture = rand() % 2;
if(texture == 1)
{
Bump_map(ipx,ipy,ipz,dx,dy,dz,1,&nx,&ny,&nz,2);
rgb_color = Compute_Color(shadow_flag, ipx, ipy, ipz, nx, ny, nz, ia, ka_S[1], kd_S[1], ks_S[1], ns_S[1], krg_S[1], ktg_S[1], 1);
}
else
rgb_color = Compute_Color(shadow_flag, ipx, ipy, ipz, nx, ny, nz, ia, ka_S[1], kd_S[1], ks_S[1], ns_S[1], krg_S[1], ktg_S[1], 1);
break;
/* The current ray intercepts sphere #3. */
case 3 :
nx = ipx - c[2][0];
ny = ipy - c[2][1];
nz = ipz - c[2][2];
Normalize(&nx, &ny, &nz);
shadow_flag = 0;
shadow_flag = Check_Shadow(ipx, ipy, ipz, obj_num);
texture = rand() % 2;
if (texture==1) // Compute texture. */
{
Bump_map(ipx,ipy,ipz,dx,dy,dz,1,&nx,&ny,&nz,1);
rgb_color = Compute_Color(shadow_flag, ipx, ipy, ipz, nx, ny, nz, ia, tka3, tkd3, ks_S[2], ns_S[2], krg_S[2], ktg_S[2], 1);
}
else
rgb_color = Compute_Color(shadow_flag, ipx, ipy, ipz, nx, ny, nz, ia, ka_S[2], kd_S[2], ks_S[2], ns_S[2], krg_S[2], ktg_S[2], 1);
break;
case 4 : /* The current ray intercepts plane #1. */
nx = p[0][0];
ny = p[0][1];
nz = p[0][2];
shadow_flag = 0;
shadow_flag = Check_Shadow(ipx, ipy, ipz,obj_num);
grain = wood_grain(ipx,ipy,ipz);
if(grain < 3)
rgb_color = Compute_Color(shadow_flag, ipx, ipy, ipz, nx, ny, nz, ia, tka4 ,tkd4 , ks_P[0], ns_P[0] ,krg_P[0], ktg_P[0], 1);
else
rgb_color = Compute_Color(shadow_flag, ipx, ipy, ipz, nx, ny, nz, ia, ka_P[0], kd_P[0], ks_P[0], ns_P[0], krg_P[0], ktg_P[0], 1);
break;
case 5 : /* The current ray intercepts plane #2. */
nx = p[1][0];
ny = p[1][1];
nz = p[1][2];
shadow_flag = 0;
shadow_flag = Check_Shadow(ipx, ipy, ipz,obj_num);
if (ipz < 2.0 || (ipz>=4.0 && ipz<6.0)) {
if ((ipy>=2.0 && ipy<4.0) || (ipy>=6.0))
texture = 1;
else
texture = 0;
}
else {
if ((ipy<2.0) || (ipy>=4.0 && ipy<6.0))
texture = 1;
else
texture = 0;
}
if (texture == 1)
rgb_color = Compute_Color(shadow_flag, ipx, ipy, ipz, nx, ny, nz, ia, tka5, tkd5, ks_P[1], ns_P[1], krg_P[1], ktg_P[1], 1);
else
rgb_color = Compute_Color(shadow_flag, ipx, ipy, ipz, nx, ny, nz, ia, ka_P[1], kd_P[1], ks_P[1], ns_P[1], krg_P[1], ktg_P[1], 1);
break;
case 6 : /* The current ray intercepts plane #3. */
nx = p[2][0];
ny = p[2][1];
nz = p[2][2];
shadow_flag = 0;
shadow_flag = Check_Shadow(ipx, ipy, ipz,obj_num);
if (ipx < 2.0 || (ipx >= 4.0 && ipx < 6.0)) {
if ((ipz >= 2.0 && ipz < 4.0) || (ipz >=6.0))
texture = 1;
else
texture = 0;
}
else {
if ((ipz<2.0) || (ipz>=4.0 && ipz<6.0))
texture = 1;
else
texture = 0;
}
t = turbulence(ipx,ipy,ipz,0.5);
value = ipx+t;
x = sqrt( value + 1.0)*0.7071;
get_marble_color( (float)sin(value*3.1415926), &rgb_color);
get_marble_color( (float)sin(value*3.1415926), &rgb_color);
get_marble_color( (float)sin(value*3.1415926), &rgb_color);
/*if (texture == 1)
rgb_color = Compute_Color(shadow_flag, ipx, ipy, ipz, nx, ny, nz, ia, tka6, tkd6, ks_P[2], ns_P[2], krg_P[2], ktg_P[2], 1);
else
rgb_color = Compute_Color(shadow_flag, ipx, ipy, ipz, nx, ny, nz, ia, ka_P[2], kd_P[2], ks_P[2], ns_P[2], krg_P[2], ktg_P[2], 1);
*/
break;
default:
break;
}
if(depth < MAX_DEPTH)
{
if(obj_num > 0 && obj_num !=4 && nx >= 0 && ny >= 0 && nz >= 0)
{
compute_reflected_ray(dx, dy, dz, nx, ny, nz, &rlx, &rly, &rlz);
points newFrom;
newFrom.x = ipx;
newFrom.y = ipy;
newFrom.z = ipz;
rgb rcolor = Ray_Trace(obj_num,rlx,rly,rlz,newFrom,depth+1);
switch(obj_num)
{
case 1:
rgb_color.r += krg_S[0]*rcolor.r;
rgb_color.g += krg_S[0]*rcolor.g;
rgb_color.b += krg_S[0]*rcolor.b;
break;
case 2:
rgb_color.r += krg_S[1]*rcolor.r;
rgb_color.g += krg_S[1]*rcolor.g;
rgb_color.b += krg_S[1]*rcolor.b;
break;
case 3:
rgb_color.r += krg_S[2]*rcolor.r;
rgb_color.g += krg_S[2]*rcolor.g;
rgb_color.b += krg_S[2]*rcolor.b;
break;
case 4:
rgb_color.r += krg_P[0]*rcolor.r;
rgb_color.g += krg_P[0]*rcolor.g;
rgb_color.b += krg_P[0]*rcolor.b;
break;
case 5:
rgb_color.r += krg_P[1]*rcolor.r;
rgb_color.g += krg_P[1]*rcolor.g;
rgb_color.b += krg_P[1]*rcolor.b;
break;
case 6:
rgb_color.r += krg_P[2]*rcolor.r;
rgb_color.g += krg_P[2]*rcolor.g;
rgb_color.b += krg_P[2]*rcolor.b;
break;
default:
break;
}
}
float n1 = 1.0003; /*refractive index air*/
/*nt - refractive index material*/
float thetha = 1000;
if(obj_num > 0 && obj_num < 7)
{
if(obj_num < 4)
{
thetha = asin((float)n1/(float)nt_S[obj_num-1]);
if(thetha < 41.2) /* Check if object is semi transparent */
{
points newFrom;
newFrom.x = ipx;
newFrom.y = ipy;
newFrom.z = ipz;
compute_refracted_ray(dx,dy,dz,nx,ny,nz,&rfx,&rfy,&rfz,nt_S[obj_num-1]); /*Compute refracted ray*/
rgb rcolor = Ray_Trace(obj_num,rfx,rfy,rfz,newFrom,depth+1);
rgb_color.r += ktg_P[0]*rcolor.r;
rgb_color.g += ktg_P[0]*rcolor.g;
rgb_color.b += ktg_P[0]*rcolor.b;
}
}
else
{
int i = obj_num-NUM_SPHERES-1;
thetha = asin((float)n1/(float)nt_P[i]);
if(thetha < 41.2) /* Check if object is semi transparent */
{
points newFrom;
newFrom.x = ipx;
newFrom.y = ipy;
newFrom.z = ipz;
compute_refracted_ray(dx,dy,dz,nx,ny,nz,&rfx,&rfy,&rfz,nt_P[i]); /*Compute refracted ray*/
rgb rcolor = Ray_Trace(obj_num,rfx,rfy,rfz,newFrom,depth+1);
rgb_color.r += ktg_P[0]*rcolor.r;
rgb_color.g += ktg_P[0]*rcolor.g;
rgb_color.b += ktg_P[0]*rcolor.b;
}
}
}
}
return rgb_color;
}
