const Intersection findFirstIntersection(const Line& ray,
double minDist, double maxDist) {
Intersection intersection;
for(int i=0; i<geometryCount; i++) {
Intersection in = scene[i]->getIntersection(ray, minDist, maxDist);
if(in.valid()) {
if(!intersection.valid()) {
intersection = in;
}
else if(in.t() < intersection.t()) {
intersection = in;
}
}
}
return intersection;
}
Intersection GridEntry::intersect(Ray r, bool computeNorm, unsigned int *int_test, unsigned int *int_hit) {
Intersection bestIsect(9.9e99, false);
if (objects.size()==0) {
return bestIsect;
}
Intersection curIsect;
for (ObjectList::iterator obj_iter = objects.begin();
obj_iter != objects.end();
++obj_iter) {
curIsect = (*obj_iter)->intersect(r, computeNorm);
(*int_test)++;
if (curIsect.hits()) {
++(*int_hit);
if (curIsect.t()<bestIsect.t()) {
bestIsect = curIsect;
bestIsect.setGridEntry(this);
}
}
}
return bestIsect;
}
Color Scene::shade(Intersection isect, Ray r, int level) {
if (!isect.hits()) {
return bgColor;
}
real eps;
if (r.in()) {
eps = 0.00001;
} else {
eps = -0.00001;
}
Texture *txt = isect.object()->getTexture();
Point isectPt = r.pointOn(isect.t());
Color curColor(0.0,0.0,0.0);
Color specular(0,0,0);
Color diffuse(0,0,0);
Color shadowAmt(1,1,1);
for (LightList::iterator lt_iter = lights.begin();
lt_iter != lights.end();
++lt_iter) {
Vector specL((*lt_iter)->location()-isectPt);
Vector specV(cam.getLocation()-isectPt);
Vector specHj((specL+specV)*(1.0/((specL+specV).length())));
Ray shade_ray = (*lt_iter)->getRayTo(r.pointOn(isect.t()+ eps));
++shadow_rays_cast;
Intersection tempI = rtrace(shade_ray, true, isect.object());
if (tempI.hits()) {
if (level>0) {
shadowAmt -= shade(tempI, shade_ray, level-1);
} else {
shadowAmt = Color(0.0,0.0,0.0);
}
}
specular += (*lt_iter)->intensity()*std::pow(specHj.dot(isect.normal()), txt->n());
diffuse += (*lt_iter)->intensity()*shade_ray.getDir().dot(isect.normal());
}
shadowAmt *= 1.0/real(lights.size());
Color reflective(0.0,0.0,0.0,0.0);
if ((level>0)
&& (txt->kr().intensity()>0.01)) {
++reflective_rays_cast;
Ray tempRay(r.pointOn(isect.t()+eps),
r.getDir()
- 2.0
* (r.getDir().dot(isect.normal()))
* isect.normal());
reflective = shade(rtrace(tempRay), tempRay, level-1);
}
Color refractive(0.0,0.0,0.0);
if ((level>0)
&& (txt->kt().intensity()>0.01)) {
real eta;
if (r.in()) {
eta = 1.0/txt->ior();
} else {
eta = txt->ior();
}
real ci;
if (r.in()) {
ci = (r.getDir().dot(-1.0*isect.normal()));
} else {
ci = (r.getDir().dot(isect.normal()));
}
real costt = 1.0 - (eta*eta) * (1.0-ci*ci);
if (costt<0.0) {
refractive = Color(0,0,0);
} else {
++refractive_rays_cast;
Ray tempRay(r.pointOn(isect.t()+eps),
((eta*ci-std::sqrt(costt))*((r.in()?-1.0:1.0)*isect.normal())
- (eta*r.getDir())),
!r.in());
refractive = shade(rtrace(tempRay, isect.object()), tempRay, level-1);
}
}
curColor +=
txt->ka()
+ (txt->kd()*diffuse
+ txt->ks()*specular
+ txt->kr()*reflective
+ txt->kt()*refractive)
* shadowAmt;
return curColor.clamp();
}
