Color refraction_shader::Shade( const Scene &scene, const HitInfo &hit ) const{
if(gen >= max_depth)
return scene.envmap->Shade(hit.ray);
if( mat->emission != black )
if (_ray.type == indirect_ray) //turnign off the light
return black;
else
return mat->emission; //this si direct sample, so return illum of the light
if(mat->reflectivity != black && _ray.type == indirect_ray)
return black;
Vec3 O = _ray.origin;
Vec3 P = hit.point;
Vec3 N = hit.normal;
Vec3 E = Unit( O - P );
Vec3 R = Unit( ( 2.0 * ( E * N ) ) * N - E );
if( E * N < 0.0 ) N = -N; //flip the normal to make it point into the space of the ray origin
if(mat->translucency != black ){
Ray rr = obj->getRefracetedRay(_ray,P,N);
if(rr.direction!=Vec3(0,0,0))
return scene.Trace(rr)*mat->translucency
+ scene.Trace(obj->getReflectedRay(_ray,P,N))*(white-mat->translucency);
else return black;//this is TIR even after 4 level of internal reflections
}
unsigned k = 1,n = 1;
if(gen == 1 ){ // rays of tree depth = 1
n = numDirectRays;
k = numIndirectRays;
}
Color color = mat->diffuse * mat->ambient;
Sample *dSamples = new Sample[n*n];
unsigned numSamples;
HitInfo dHit;
Ray dRay,iRay;
unsigned Y = scene.NumLights() ;
for( unsigned i = 0; i < Y; i++ ){
const Object *light = scene.GetLight(i);
numSamples = light->GetSamples (hit.point, hit.normal, dSamples, n);
//#pragma omp parallel for
for(unsigned j=0;j<numSamples ;j++){
dRay.origin = hit.point + Unit(N)*10E-4;
dRay.direction = Unit( dSamples[j].P - hit.point );
dRay.generation = gen + 1; //next level in tree
dHit.ray = dRay;
dHit.distance = Infinity;
dRay.type = _ray.type;
if(scene.Cast(dRay,dHit))
if( dHit.object == light){
color += max( 0, dRay.direction*Unit(N) )*
mat->diffuse*
light->material->emission*dSamples[j].w/Pi;
if( mat->Phong_exp !=0 && mat->specular != black)
//this si handling specularity
color += (white-mat->reflectivity)*
pow( max( dRay.direction*R,0), mat->Phong_exp) *
mat->specular*light->material->emission*dSamples[j].w;
}
else if(dHit.object->material->translucency != black){
//hit a tranclusive surface, so cast the transmitted ray
Ray rr = dHit.object->getRefracetedRay(dRay,dHit.point, dHit.normal);
HitInfo rrHit;
rrHit.distance = Infinity;
rrHit.ray = rr;
if(scene.Cast(rr,rrHit))
if(rrHit.object == light)
color += max( 0, dRay.direction*Unit(N) )*
mat->diffuse*
light->material->emission*dSamples[j].w/Pi;
if( mat->Phong_exp !=0 && mat->specular != black)
color += (white-mat->reflectivity)*
pow( max( dRay.direction*R,0), mat->Phong_exp) *
mat->specular*light->material->emission*dSamples[j].w;
}
}
}
if(mat->reflectivity == black){
//sample hmisphere (stratified)
if(max_depth > 2){
Sample* iSamples = new Sample[k*k];
numSamples = SampleProjectedHemisphere (hit.point, hit.normal, iSamples, k);
//#pragma omp parallel for
for(unsigned j = 0; j < numSamples ;j++){
iRay.origin = hit.point + Unit(N)*10E-4;
iRay.from = obj;
iRay.direction = Unit( hit.point - iSamples[j].P );
iRay.generation = gen+ 1;
iRay.type = indirect_ray;
color += (mat->diffuse*iSamples[j].w*scene.Trace(iRay))/TwoPi;
}
delete [] iSamples;
iSamples = NULL;
}
}
else{
Ray rr;
rr.origin = P+ N*10E-4;
rr.direction = R;
rr.from = obj;
rr.ignore = NULL;
rr.generation = gen+1;
color = color*(white - mat->reflectivity);
color += mat->reflectivity*scene.Trace(rr);
}
delete [] dSamples;
dSamples = NULL;
return color;
}
// Shade assigns a color to a point on a surface, as it is seen
// from another point. The coordinates of these points, the normal
// of the surface, and the surface material are all recorded in the
// HitInfo structure. The shader will typically make calls to Trace
// to handle shadows and reflections.
Color Raytracer::Shade(const HitInfo &hit, const Scene &scene, int max_tree_depth)
{
Color color = { 0.0f, 0.0f, 0.0f };
Vec3 point = hit.geom.point + hit.geom.normal*Epsilon;
HitInfo hitObstacle = hit;
Ray ray, ray2;
Color diffuse = Color(0,0,0), specular = Color(0,0,0);
Color direct = Color(0,0,0), indirect = Color(0,0,0);
Sample lightPoint;
Vec3 V;
Color irradiant = Color(0,0,0);
int espec = 0;
Color indirect_hemisphere = Color(0, 0, 0), indirect_lobe = Color(0, 0, 0);
//if (max_tree_depth >= 0) {
if (hit.material.Emitter()) {
return hit.material.m_Diffuse;
}else{
for (Object *object = scene.first; object != NULL; object = object->next)
{
if (object->material.Emitter() == true)
{
lightPoint = object->GetSample(hit.geom.point, hit.geom.normal);
ray.origin = hit.geom.point;
//lightPoint.P = lightPoint.P + hit.geom.normal*Epsilon;
ray.direction = Unit(lightPoint.P - hit.geom.point);
hitObstacle.geom.distance = Length(lightPoint.P - point);
V = Unit(hit.geom.origin - hit.geom.point);
Vec3 N = (hit.geom.normal);
Vec3 H = Unit(V + ray.direction);
//V = Unit(hit.geom.origin - hit.geom.point);
Vec3 L = (-ray.direction);// Unit(point - lightPoint.P);
Vec3 R = Unit(Reflection(-L, N));//Unit((2*N*(N*L))-L);
espec = hit.material.m_Phong_exp;
double c = (L*H);
double g = sqrt((pow(1.4 / 1, 2.0))+ pow(c,2)-1);
Color f0 = hit.material.m_Specular;
double F = (f0.red + (1.0 - f0.red, 1.0 - f0.green, 1.0 - f0.blue)*(pow((1 - (N*V)), 5)), f0.green + (1.0 - f0.red, 1.0 - f0.green, 1.0 - f0.blue)*(pow((1 - (N*V)), 5)), f0.blue+(1.0 - f0.red, 1.0 - f0.green, 1.0 - f0.blue)*(pow((1 - (N*V)), 5)));
//double F = (1 / 2)*((pow(g - c, 2))/(pow(g + c, 2)))*(1+pow((c*(g+c)-1),2)/ (1 + pow((c*(g - c) + 1), 2)));
double D = ((espec + 2) / (2 * Pi))*(pow((H*N), espec));
//double D = 1/(sqrt(2*Pi))
double G = min(min(1.0, (2 * (N*H)*(N*V)) / (V*H)), (2 * (N*H)*(N*L)) / (L*H));
if (G < 0) G = 0;
if (D < 0) D = 0;
if (F < 0) F = 0;
if (!Cast(ray, scene, hitObstacle)) {
if (N * L > 0) {
diffuse = (N*L)*hit.material.m_Diffuse/Pi;
}
else {
diffuse = Color(0.0, 0.0, 0.0);
}
irradiant = object->material.m_Emission*(lightPoint.w);
if ((R*V) > 0 && hit.material.m_Phong_exp > 0) {
specular = /*(espec + 2)/(2*Pi) * pow((R*V), espec)*/(F*D*G / (4 * (N*L)*(N*V)))*hit.material.m_Specular;
}
else {
specular = Color(0.0, 0.0, 0.0);
}
direct += (diffuse + specular)*irradiant;
}
}
}
if (hit.material.m_Phong_exp > 0) {
Vec3 N = (hit.geom.normal);
Vec3 L = Unit(-ray.direction);
V = -Unit(hit.geom.point - hit.geom.origin);
Vec3 R = Unit(Reflection(-V, N));
Vec3 H = Unit(V + ray.direction);
double c = (L*H);
double g = sqrt((pow(1.4 / 1, 2.0)) + pow(c, 2) - 1);
Color f0 = hit.material.m_Specular;
double F = (f0.red + (1.0 - f0.red, 1.0 - f0.green, 1.0 - f0.blue)*(pow((1 - (N*V)), 5)), f0.green + (1.0 - f0.red, 1.0 - f0.green, 1.0 - f0.blue)*(pow((1 - (N*V)), 5)), f0.blue + (1.0 - f0.red, 1.0 - f0.green, 1.0 - f0.blue)*(pow((1 - (N*V)), 5)));
//double F = (1 / 2)*((pow(g - c, 2))/(pow(g + c, 2)))*(1+pow((c*(g+c)-1),2)/ (1 + pow((c*(g - c) + 1), 2)));
double D = ((espec + 2) / (2 * Pi))*(pow((H*N), espec));
double G = min(min(1.0, (2 * (N*H)*(N*V)) / (V*H)), (2 * (N*H)*(N*L)) / (L*H));
if (G < 0) G = 0;
if (D < 0) D = 0;
if (F < 0) F = 0;
float phong_exp = hit.material.m_Phong_exp;
ray2.origin = point;
Sample sample_hemisphere = SampleProjectedHemisphere(N);
ray2.direction = Unit(sample_hemisphere.P);
//ray2.no_emitters = true;
indirect_hemisphere = Trace(ray2, scene, max_tree_depth-1)* hit.material.m_Diffuse;
Sample specular_sample = SampleSpecularLobe(R, phong_exp);
ray2.direction = Unit(specular_sample.P);
indirect_lobe = Trace(ray2, scene, max_tree_depth - 1)*F*D*G / (4 * (N*L)*(N*V));// *hit.material.m_Specular;
indirect = indirect_hemisphere + indirect_lobe;// *(F*D*G / (4 * (N*L)*(N*V)));
}
return (direct) + indirect;
}
//}
}
