Ray AbstractObject::genSurfaceSample(){
Ray ray;
if(!areaThreshold.size()){
ray.direction = vec3f(0,0,0);
ray.radiance = vec3f(0,0,0);
return ray;
}
float randArea = rng->genFloat() * boundArea;
uint index = std::lower_bound(areaThreshold.begin(), areaThreshold.end(), randArea) - areaThreshold.begin();
if(index == areaThreshold.size()) index--;
ray.contactObj = this;
ray.contactTriangleID = index;
ray.origin = genRandTrianglePosition(ray.contactTriangleID);
UniformSphereSampler uniformSampler;
vec3f normal = ray.contactObj->getWorldNormal(ray.contactTriangleID, ray.origin);
ray.direction = uniformSampler.sample(*rng, vec3f(), &ray.directionProb);
if(ray.direction.dot(normal) < 0)
ray.direction = -ray.direction;
ray.radiance = ray.evalBSDF(ray);
ray.insideObj = scene->findInsideObject(ray, ray.contactObj);
ray.directionProb *= 2;
ray.originProb = 1 / boundArea * pickProb;
Scene::ObjSourceInfo info;
NoSelfCondition condition(scene, ray);
float dist = scene->intersect(ray, info, &condition);
if(dist > 0){
ray.intersectObj = scene->objects[info.objID];
ray.intersectDist = dist;
ray.intersectTriangleID = info.triID;
}
return ray;
}
Ray SceneObject::emit(bool isUniformOrigin , bool isUniformDir) const
{
Ray ray;
if(!areaValues.size())
{
ray.direction = vec3f(0, 0, 0);
ray.directionProb = 1;
ray.color = vec3f(0, 0, 0);
return ray;
}
if (isUniformOrigin)
{
float rnd = RandGenerator::genFloat()*totalArea;
unsigned index = (lower_bound(areaValues.begin(), areaValues.end(), rnd)-areaValues.begin());
if(index >= areaValues.size())
index = areaValues.size() - 1;
ray.contactObject = (SceneObject*)this;
ray.contactObjectTriangleID = index;
ray.origin = genRandTrianglePosition(ray.contactObjectTriangleID);
ray.originProb = weight / totalArea;
}
else
{
float rnd = RandGenerator::genFloat()*totalEnergy;
unsigned index = (lower_bound(energyDensity.begin(), energyDensity.end(), rnd)-energyDensity.begin());
if(index >= energyDensity.size())
index = energyDensity.size() - 1;
ray.contactObject = (SceneObject*)this;
ray.contactObjectTriangleID = index;
ray.origin = genRandTrianglePosition(ray.contactObjectTriangleID);
float prob;
if (index == 0)
prob = energyDensity[index] / totalEnergy;
else
prob = (energyDensity[index] - energyDensity[index - 1]) / totalEnergy;
ray.originProb = weight * prob / areaValues[index];
}
UniformSphericalSampler uniformSphericalSampler;
CosineSphericalSampler cosineSphericalSampler;
LocalFrame lf = ray.contactObject->getAutoGenWorldLocalFrame(ray.contactObjectTriangleID, ray.origin);
if (isUniformDir)
ray.direction = uniformSphericalSampler.genSample(lf);
else
ray.direction = cosineSphericalSampler.genSample(lf);
if(ray.getContactNormal().dot(ray.direction) < 0)
ray.direction = -ray.direction;
ray.insideObject = scene->findInsideObject(ray, ray.contactObject);
ray.current_tid = scene->getContactTreeTid(ray);
ray.color = ray.getBSDF(ray);
if(!emissive())
ray.color = vec3f(1, 1, 1);
if (isUniformDir)
ray.directionProb = uniformSphericalSampler.getProbDensity(lf , ray.direction) * 2.f;
else
ray.directionProb = cosineSphericalSampler.getProbDensity(lf, ray.direction);
ray.directionSampleType = ray.originSampleType = Ray::RANDOM;
if(!scene->usingGPU())
{
Scene::ObjSourceInformation osi;
NoSelfIntersectionCondition condition(scene, ray);
float dist = scene->intersect(ray, osi, &condition);
if(dist > 0)
{
ray.intersectDist = dist;
ray.intersectObject = scene->objects[osi.objID];
ray.intersectObjectTriangleID = osi.triangleID;
}
}
return ray;
}
