LocalFrame SceneObject::getAutoGenWorldLocalFrame(unsigned fi, const vec3f& position, bool flat) const
{
LocalFrame lf;
lf.buildFromNormal(getWorldNormal(fi, position, flat));
/*
lf.n = getWorldNormal(fi, position, flat);
vec3f tmpT;
tmpT = (std::abs(lf.n.z) > 0.99f) ? vec3f(1,0,0) : vec3f(0,0,1);
lf.s = lf.n.cross(tmpT);
lf.s.normalize();
lf.t = lf.s.cross(lf.n);
lf.t.normalize();
*/
/*
vec3f axis = up.cross(lf.n);
float angle = acos(clampf(up.dot(lf.n), -1, 1));
if (!(axis.length() >= 1e-6f || (axis.length() < 1e-6f && n.dot(lf.n) == 1.f)))
{
printf("error , %.8f\n" , n.dot(lf.n));
}
axis.normalize();
//if (axis.length() < 1e-6f)
//{
// lf.s = vec3f(1,0,0);
// lf.t = vec3f(0,0,1);
//}
//else
{
lf.s = vec3f(rotMat(axis, angle)*vec4<float>(vec3f(1,0,0), 0));
lf.t = vec3f(rotMat(axis, angle)*vec4<float>(vec3f(0,0,1), 0));
}
*/
return lf;
}
float GlossyMaterial::getDirectionSampleProbDensity(const Ray& inRay, const Ray& outRay) const
{
if(!outRay.contactObject)
return 0;
LocalFrame lf;
vec3f normal = outRay.getContactNormal();
vec3f reflDir = -normal.dot(inRay.direction)*normal*2 + inRay.direction;
lf.buildFromNormal(reflDir);
vec3f coeff = coeffTex.getColor(outRay.contactObject->getTexCoord(outRay.contactObjectTriangleID, outRay.origin));
return cosineSphericalSampler.getProbDensity(lf, outRay.direction, coeff.x);
}
float SceneVPMObject::getDirectionSampleProbDensity(const Ray &inRay, const Ray &outRay) const{
if(outRay.directionSampleType == Ray::DEFINITE)
return 0;
if(outRay.contactObject)
return outRay.contactObject->getDirectionSampleProbDensity(inRay, outRay);
HGPhaseSampler hgPhaseSampler(g);
LocalFrame lf; lf.buildFromNormal(inRay.direction);
float albedo = y(ds) / y(dt);
float oPdfW = hgPhaseSampler.getProbDensity(lf, outRay.direction);
return albedo*oPdfW;
}
Ray SceneVPMObject::scatter(const Ray& inRay, const bool fixIsLight, const bool russian) const
{
Ray outRay;
outRay.directionSampleType = Ray::RANDOM;
HomoMediaDistSampler logDistSampler(dt);
float sampDist = logDistSampler.sampleDist();
bool go_in_vol = (inRay.intersectObject == this) && (inRay.insideObject != this);
bool be_in_vol = (inRay.insideObject == this);
bool out_of_vol = (sampDist >= inRay.intersectDist); // hit a surface
// go in volume
if(go_in_vol){
vec3f position = inRay.origin + inRay.direction*inRay.intersectDist;
LocalFrame lf = inRay.intersectObject->getAutoGenWorldLocalFrame(inRay.intersectObjectTriangleID, position, flatNormals);
vec3f normal = lf.n;
outRay.origin = position;
outRay.direction = inRay.direction;
vec3f reflDir = -normal.dot(inRay.direction)*normal*2 + inRay.direction;
reflDir.normalize();
float theta = acos(inRay.direction.dot(normal));
SceneObject* currentInsideObject = inRay.insideObject;
SceneObject* outSideObject = (SceneObject*)this;
float current_n = currentInsideObject ? currentInsideObject->getRefrCoeff() : 1;
float next_n = outSideObject ? outSideObject->getRefrCoeff() : 1;
float sin_phi = current_n / next_n * sin(theta);
outRay.intersectObject = NULL;
outRay.color = vec3f(1, 1, 1);
outRay.directionProb = 1;
outRay.contactObject = (SceneObject*)this;
outRay.contactObjectTriangleID = inRay.intersectObjectTriangleID;
if(sin_phi >= 1){ // no total internal reflection
outRay.direction = vec3f(0.f);
outRay.contactObject = NULL;
outRay.contactObjectTriangleID = -1;
outRay.directionSampleType = Ray::DEFINITE;
return outRay;
// outRay.direction = reflDir;
// outRay.insideObject = inRay.insideObject;
// outRay.directionProb = 1;
// outRay.directionSampleType = Ray::DEFINITE;
// outRay.photonType = Ray::NOUSE;
// outRay.color /= outRay.getCosineTerm();
//if (abs(outRay.getCosineTerm() - 1.f) > 1e-6f)
// printf("exception1: %.6f\n" , outRay.getCosineTerm());
}
else{
float phi = asin(sin_phi);
if(theta > M_PI/2)
phi = M_PI - phi;
vec3f axis = normal.cross(inRay.direction);
axis.normalize();
outRay.direction = vec3f(rotMat(axis, phi) * vec4<float>(normal, 0));
outRay.direction.normalize();
float cos_theta = abs(cos(theta));
float cos_phi = abs(cos(phi));
float esr = powf(abs(current_n*cos_theta-next_n*cos_phi)/(current_n*cos_theta+next_n*cos_phi),2);
float epr = powf(abs(next_n*cos_theta-current_n*cos_phi)/(next_n*cos_theta+current_n*cos_phi),2);
float er = (esr+epr)*0.5f;
float p = clampf(er , 0.f , 1.f);
if(RandGenerator::genFloat() < p)
{
outRay.direction = reflDir;
outRay.color *= er / outRay.getCosineTerm();
outRay.directionProb = p;
outRay.insideObject = inRay.insideObject;
outRay.directionSampleType = Ray::DEFINITE;
outRay.photonType = Ray::NOUSE;
}
else
{
if (!fixIsLight) outRay.color *= (current_n * current_n) / (next_n * next_n);
//printf("go in: %.6f/%.6f\n" , current_n , next_n);
outRay.color *= (1-er) / outRay.getCosineTerm();
outRay.directionProb = 1-p;
outRay.contactObject = outRay.insideObject = (SceneObject*)this;
outRay.directionSampleType = Ray::DEFINITE;
outRay.photonType = Ray::HITVOL;
}
outRay.direction.normalize();
}
return outRay;
}
// in volume
if(be_in_vol && !out_of_vol){
HGPhaseSampler hgPhaseSampler(g);
//IsotropicPhaseSampler sp;
LocalFrame lf; lf.buildFromNormal(inRay.direction);
outRay.origin = inRay.origin + inRay.direction * sampDist;
outRay.direction = hgPhaseSampler.genSample(lf);
outRay.color = bsdf->evaluate(lf, inRay.direction, outRay.direction);
outRay.insideObject = (SceneObject*)this;
//outRay.contactObject = NULL;
outRay.contactObjectTriangleID = inRay.intersectObjectTriangleID;
//outRay.contactObjectTriangleID = -1;
//outRay.directionProb = 1;
//outRay.color = vec3f(1, 1, 1);
float albedo = y(ds) / y(dt);
float rander = RandGenerator::genFloat();
//outRay.originSampleType = Ray::RANDOM;
if(rander < albedo || (!russian)){
outRay.contactObject = NULL;
float oPdfW = hgPhaseSampler.getProbDensity(lf, outRay.direction);//sp.getProbDensity(lf, outRay.direction);//
if (russian)
outRay.directionProb = albedo * oPdfW;
else
outRay.directionProb = oPdfW;
outRay.originProb = p_medium(sampDist);
outRay.directionSampleType = Ray::RANDOM;
outRay.color *= ds;
outRay.photonType = Ray::INVOL;
}
else{
// terminate
outRay.direction = vec3f(0, 0, 0);
outRay.color = vec3f(0, 0, 0);
outRay.directionProb = 1;
outRay.originProb = p_medium(sampDist);
outRay.insideObject = (SceneObject*)this; // FIXED
//outRay.insideObject = NULL;
outRay.contactObject = NULL;
outRay.directionSampleType = Ray::RANDOM;
outRay.photonType = Ray::INVOL;
//outRay.photonType = Ray::NOUSE;
}
return outRay;
}
// go out of volume
if(be_in_vol && out_of_vol){
outRay = inRay;
outRay.direction = inRay.direction;
outRay.origin = inRay.origin + inRay.intersectDist * inRay.direction;
outRay.contactObject = inRay.intersectObject;
outRay.contactObjectTriangleID = inRay.intersectObjectTriangleID;
outRay.insideObject = (SceneObject*)this;
outRay.directionProb = 1;
outRay.color = vec3f(1,1,1);
bool going_out = (inRay.intersectObject == this);
if(going_out){
LocalFrame lf = inRay.intersectObject->getAutoGenWorldLocalFrame(inRay.intersectObjectTriangleID, outRay.origin, flatNormals);
vec3f normal = lf.n;
vec3f reflDir = -normal.dot(inRay.direction)*normal*2 + inRay.direction;
reflDir.normalize();
float theta = acos(inRay.direction.dot(normal));
SceneObject* currentInsideObject = (SceneObject*)this;
SceneObject* outSideObject = scene->findInsideObject(outRay, (SceneObject*)this);
float current_n = currentInsideObject ? currentInsideObject->getRefrCoeff() : 1;
float next_n = outSideObject ? outSideObject->getRefrCoeff() : 1;
float sin_phi = current_n / next_n * sin(theta);
outRay.intersectObject = NULL;
if(sin_phi >= 1){ // no total internal reflection
outRay.direction = vec3f(0.f);
outRay.contactObject = NULL;
outRay.contactObjectTriangleID = -1;
outRay.directionSampleType = Ray::DEFINITE;
return outRay;
// outRay.direction = reflDir;
// outRay.insideObject = inRay.insideObject;
// outRay.contactObject = (SceneObject*)this;
// outRay.originProb = P_surface(inRay.intersectDist);
// outRay.photonType = Ray::NOUSE;
// outRay.directionSampleType = Ray::DEFINITE;
// outRay.color /= outRay.getCosineTerm();
//if (abs(outRay.getCosineTerm() - 1.f) > 1e-6f)
// printf("exception2: %.6f\n" , outRay.getCosineTerm());
}
else{
float phi = asin(sin_phi);
if(theta > M_PI/2)
phi = M_PI - phi;
vec3f axis = normal.cross(inRay.direction);
axis.normalize();
outRay.direction = vec3f(rotMat(axis, phi) * vec4<float>(normal, 0));
outRay.direction.normalize();
float cos_theta = abs(cos(theta));
float cos_phi = abs(cos(phi));
float esr = powf(abs(current_n*cos_theta-next_n*cos_phi)/(current_n*cos_theta+next_n*cos_phi),2);
float epr = powf(abs(next_n*cos_theta-current_n*cos_phi)/(next_n*cos_theta+current_n*cos_phi),2);
float er = (esr+epr)/2.f;
float p = clampf(er , 0.f , 1.f);
if(RandGenerator::genFloat() < p)
{
outRay.direction = reflDir;
outRay.color *= er / outRay.getCosineTerm();
outRay.directionProb = p;
outRay.originProb = P_surface(inRay.intersectDist);
outRay.insideObject = inRay.insideObject;
outRay.directionSampleType = Ray::DEFINITE;
outRay.photonType = Ray::NOUSE;
}
else
{
if (!fixIsLight) outRay.color *= (current_n * current_n) / (next_n * next_n);
//printf("go out: %.6f/%.6f\n" , current_n , next_n);
outRay.color *= (1-er) / outRay.getCosineTerm();
outRay.directionProb = (1-p);
outRay.originProb = P_surface(inRay.intersectDist);
outRay.insideObject = outSideObject;
outRay.directionSampleType = Ray::DEFINITE;
outRay.photonType = Ray::NOUSE;
}
outRay.direction.normalize();
}
}
else{
//std::cout << "in vol hit surface " << std::endl;
outRay.contactObject = NULL;
outRay.intersectDist = 0;
//------ FIX ME -------
if (inRay.intersectObject != NULL)
outRay = inRay.intersectObject->scatter(outRay , fixIsLight , russian);
else
printf("error VPM object scattering\n");
//---------------------
outRay.originProb *= P_surface(inRay.intersectDist);
outRay.photonType = inRay.intersectObject->isVolumetric() ? Ray::NOUSE : Ray::OUTVOL;
}
return outRay;
}
printf("error at SceneVPMObject: should not reach here\n");
return outRay;
}
