Color ray_shade(int level, Real w, Ray v, RContext *rc, Object *ol)
{
Inode *i = ray_intersect(ol, v);
if (i != NULL) { Light *l; Real wf;
Material *m = i->m;
Vector3 p = ray_point(v, i->t);
Cone recv = cone_make(p, i->n, PIOVER2);
Color c = c_mult(m->c, c_scale(m->ka, ambient(rc)));
rc->p = p;
for (l = rc->l; l != NULL; l = l->next)
if ((*l->transport)(l, recv, rc) && (wf = shadow(l, p, ol)) > RAY_WF_MIN)
c = c_add(c, c_mult(m->c,
c_scale(wf * m->kd * v3_dot(l->outdir,i->n), l->outcol)));
if (level++ < MAX_RAY_LEVEL) {
if ((wf = w * m->ks) > RAY_WF_MIN) {
Ray r = ray_make(p, reflect_dir(v.d, i->n));
c = c_add(c, c_mult(m->s,
c_scale(m->ks, ray_shade(level, wf, r, rc, ol))));
}
if ((wf = w * m->kt) > RAY_WF_MIN) {
Ray t = ray_make(p, refract_dir(v.d, i->n, (i->enter)? 1/m->ir: m->ir));
if (v3_sqrnorm(t.d) > 0) {
c = c_add(c, c_mult(m->s,
c_scale(m->kt, ray_shade(level, wf, t, rc, ol))));
}
}
}
inode_free(i);
return c;
} else {
return BG_COLOR;
}
}
double rayvolume(Prim *p, double stepsize){
Ray rayo;
Vector3 vo;
Vector3 vd;
// Rays parallel to Y axis:
vd = v3_make(0,1,0);
double t0, t1;
Inode *intersect;
double i, j;
double Vol = 0.0;
for (i=-30; i<=30; i+=stepsize){
for (j=-20; j<=20; j+=stepsize){
// Origin of the rays XZ parallel plane:
vo = v3_make(j*1.0,-100,-i*1.0);
rayo = ray_make(vo,vd);
if ( prim_intersect(p,rayo) != NULL ){
t0 = prim_intersect(p,rayo)[0].t;
if (prim_intersect(p,rayo)[0].enter){
t1 = prim_intersect(p,rayo)[0].next->t;
Vol += abs(t1 - t0);
} else {
}
} else {
}
}
};
return Vol*SQR(stepsize);
}
static Real visible(int n, Poly **p, Vector3 v, Vector3 d)
{
Ray r = ray_make(v, d);
while (n--) {
Real t = poly3_ray_inter(p[n], poly3_plane(p[n]), r);
if (t > REL_EPS && t < 1)
return 0.0;
}
return 1.0;
}
Real shadow(Light *l, Vector3 p, Object *ol)
{
Real t, kt; Inode *i; Vector3 d;
if (l->type == LIGHT_AMBIENT)
return 1.0;
d = (l->type == LIGHT_DISTANT)? l->dir : v3_sub(l->loc, p);
if ((i = ray_intersect(ol, ray_make(p, d))) == NULL)
return 1.0;
t = i->t; kt = i->m->kt; inode_free(i);
if (l->type == LIGHT_DISTANT && t > RAY_EPS)
return kt;
else if (l->type != LIGHT_DISTANT && t > RAY_EPS && t < 1)
return kt;
else
return 1.0;
}
Ray ray_view(int u, int v)
{
Vector4 w = v4_m4mult(v4_make(u, v,s->view->sc.ur.z, 1), mdpy);
return ray_make(v3_v4conv(v4_m4mult(v4_make(0, 0, 1, 0), mdpy)),
v3_make(w.x, w.y, w.z));
}
