Colour RayTracer::CalculateLighting(std::vector<Light*>* lights, Vector3* campos, RayHitResult* hitresult)
{
Colour outcolour;
std::vector<Light*>::iterator lit_iter = lights->begin();
//Retrive the material for the intersected primitive
Primitive* prim = (Primitive*)hitresult->data;
Material* mat = prim->GetMaterial();
//the default output colour is the ambient colour
outcolour = mat->GetAmbientColour();
// The hack f***s stuff up.
//This is a hack to set a checker pattern on the planes
//Do not modify it
if (((Primitive*)hitresult->data)->m_primtype == Primitive::PRIMTYPE_Plane)
{
int dx = (hitresult->point[0]/2.0);
int dy = (hitresult->point[1]/2.0);
int dz = (hitresult->point[2]/2.0);
if (dx % 2 || dy % 2 || dz % 2)
{
outcolour.red = 1.0;
outcolour.green = 1.0;
outcolour.blue = 1.0;
}
else
{
outcolour.red = 0.0;
outcolour.green = 0.0;
outcolour.blue = 0.0;
}
}
////Go through all the light sources in the scene
//and calculate the lighting at the intersection point
if (m_traceflag & TRACE_DIFFUSE_AND_SPEC)
{
while (lit_iter != lights->end())
{
Vector3 light_pos = (*lit_iter)->GetLightPosition(); //position of the light source
Vector3 normal = hitresult->normal; //surface normal at intersection
Vector3 surface_point = hitresult->point; //location of the intersection on the surface
//TODO: Calculate the surface colour using the illumination model from the lecture notes
// 1. Compute the diffuse term
// 2. Compute the specular term using either the Phong model or the Blinn-Phong model
// 3. store the result in outcolour
// DONE
outcolour += CalculateDiffuseLighting((light_pos - surface_point).Normalise(), normal, **lit_iter, *mat);
outcolour += CalculateSpecularLighting(surface_point, normal, light_pos - surface_point, *campos, **lit_iter, *mat);
double dist = (light_pos - surface_point).Norm();
double att = 1.0 / (1.0 + (0 * dist) + (0.002 * dist * dist));
outcolour *= att;
lit_iter++;
}
}
// light and surface pont
return outcolour;
}
