void PhotonMapper::forwardPassRay(Ray ray, int x, int y, float weight, int depth){
Intersection is;
if (weight > 0 && depth < maxForwardPassDepth && mScene->intersect(ray, is)){
Hitpoint* hp = new Hitpoint();
hp->pixelX = x;
hp->pixelY = y;
hp->is = is;
hp->radius = startRadius;
Color reflectedC, refractedC, emittedC;
Material* m = is.mMaterial;
float reflectivity = m->getReflectivity(is);
float transparency = m->getTransparency(is);
float diffuse = (1.0f - reflectivity - transparency)*weight;
hp->pixelWeight = (1.0f - reflectivity - transparency) * weight;
if (reflectivity > 0.0f) {
Ray reflectedRay = is.getReflectedRay();
forwardPassRay(reflectedRay, x, y, reflectivity * weight, depth+1);
}
if (transparency > 0.0f) {
Ray refractedRay = is.getRefractedRay();
forwardPassRay(refractedRay, x, y, transparency * weight, depth+1);
}
if (diffuse){
for (int i = 0; i < mScene->getNumberOfLights(); ++i){
PointLight* l = mScene->getLight(i);
if (!mScene->intersect(is.getShadowRay(l))){
Vector3D lightVec = l->getWorldPosition() - is.mPosition;
float d2 = lightVec.length2();
lightVec.normalize();
Color radiance = l->getRadiance();
Color brdf = is.mMaterial->evalBRDF(is, lightVec);
float angle = max(lightVec * is.mNormal, 0.0f);
hp->directIllumination += radiance * brdf * angle / d2;
}
}
vec.push_back(hp);
}
}
}
void PhotonMapper::photonTracingPass(){
for (int i = 0; i < mScene->getNumberOfLights(); ++i){
PointLight* l = mScene->getLight(i);
for (int i = 0; i < numberPhotons; ++i){
Vector3D dir(uniform() * 2 - 1, uniform() * 2 - 1, uniform() * 2 - 1);
while(dir.length2() > 1.0f){
dir = Vector3D(uniform() * 2 - 1, uniform() * 2 - 1, uniform() * 2 - 1);
}
dir.normalize();
Ray ray;
ray.orig = l->getWorldPosition();
ray.dir = dir;
Color startFlux = l->getRadiance() * 4.0f * M_PI;
trace(ray, 0, startFlux);
}
}
}