Tcolor Tmaterial::sampleSelfColor()
{
if(m_selfTexture)
{
return Tcolor(1,1,1);
}else
{
return selfColor ();
}
}
Tcolor TrayTracer::radianceWithExplicitLight(Tray ray,int reflectLevel)
{
if(reflectLevel <= 0)
return Tcolor(0,0,0);
Tcolor finalColor(0,0,0);
auto result = scene()->intersect(ray);
if (result.geometry()) {
auto material = result.geometry ()->material ();
if(!material) return finalColor;
Tcolor selfColor = material->sampleSelfColor ();
//**********Emission.
auto emissionColor = selfColor*material->emission ();
//reflect
Tcolor reflectColor;
auto allLights = scene()->getLightList();
for(int i =0;i<allLights.size ();i++)
{
TexplicitLight * light = allLights[i];
if(!light->isVisible (result.pos (),scene())) continue;
//get the irradiance from the explicit light source.
auto lightDir = light->getDir (result.pos ());
auto lightRadiance = light->getIrradiance (result.pos (),result.normal (),scene());
reflectColor += lightRadiance * material->BRDF (-ray.direction (),-lightDir,result.normal ());
}
//ideal specular radiance from other object.
if(material->reflectiveness () > 0)
{
// get the ideal specular ray.
auto reflectVec = reflect(ray.direction (),result.normal ());
auto reflectRay = Tray(result.pos (),reflectVec);
auto idealSpecularRadiance = radianceWithExplicitLight(reflectRay,reflectLevel - 1);
reflectColor +=idealSpecularRadiance * material->BRDF (-ray.direction (),reflectVec,result.normal ());
}
//render euqation.
finalColor = emissionColor+ selfColor*reflectColor*material->reflectiveness ();
}
return finalColor;
}
Tcolor TrayTracer::radiancePathTracer(Tray ray, int reflectLevel)
{
if(reflectLevel <=0) return Tcolor(0,0,0);
auto result = scene()->intersect(ray);
if (result.geometry()) {
auto material = result.geometry ()->material ();
auto emissionColor = material->sampleSelfColor () * material->emission ();
auto reflectColor = Tcolor(0,0,0);
switch(material->getType ())
{
case Tmaterial::MaterialType::Mirror://ideal specular object.
{
auto reflectVec = reflect(ray.direction (),result.normal ());
auto reflectRay = Tray(result.pos (),reflectVec);
auto idealSpecularRadiance = radiancePathTracer(reflectRay,reflectLevel - 1);
reflectColor +=idealSpecularRadiance * material->BRDF (-ray.direction (),reflectVec,result.normal ());
}
break;
case Tmaterial::MaterialType::Light://ideal emission object.
{
reflectColor = Tcolor(0,0,0);
}
break;
case Tmaterial::MaterialType::BlinnPhong:
{
}
break;
case Tmaterial::MaterialType::Diffuse:
{
Tvector nl;
if(Tvector::dotProduct (result.normal (),ray.direction ())<0)
{
nl = result.normal ();
}else
{
nl = result.normal ().negatived();
}
double r1=2*TbaseMath::PI*TbaseMath::randF ();
double r2=TbaseMath::randF ();
double r2s=sqrt(r2);
Tvector w=nl;
Tvector u;
if(fabs(w.x())>0.1)
{
u = Tvector(0,1,0);
}else
{
u = Tvector(1,0,0);
}
u = Tvector::crossProduct (u,w);
u.normalize ();
Tvector v=Tvector::crossProduct (w,u);
Tvector dir = (u*cos(r1)*r2s + v*sin(r1)*r2s + w*sqrt(1-r2)).normalized();
reflectColor = radiancePathTracer(Tray(result.pos (),dir),reflectLevel - 1);
}
break;
}
return emissionColor + material->selfColor () * reflectColor * material->reflectiveness ();
}
return Tcolor(0,0,0);
}
