public Material()
{
Properties = new ShadingInfos
{
Ambient = DEFAULT_AMBIENT,
};
}
private RTColor Shading(LocalGeo geo, ShadingInfos si, Ray camRay, Ray lightRay, RTColor lightCol)
{
float nDotL = RTVector.DotProduct(geo.Normal, lightRay.Vector);
RTColor lambert = lightCol * si.Diffuse * (nDotL > 0 ? nDotL : 0.0f);
RTVector half = (lightRay.Vector - camRay.Vector.Normalize()).Normalize();
float nDotH = RTVector.DotProduct(geo.Normal, half);
RTColor phong = lightCol * si.Specular * (float)Math.Pow((nDotH > 0 ? nDotH : 0.0f), si.Shininess);
float r = lightRay.Directional ? 0 : lightRay.TMax; // Dans le cas d'un point, le t max est la distance entre le point et la source
RTColor res = (lambert + phong) / (Attenuation.Constant + Attenuation.Linear * r + Attenuation.Quadratic * (float)Math.Pow(r, 2));
return(res);
}
public RTColor Trace(Ray ray, int depth)
{
RTColor res = new RTColor();
float lastT = float.MaxValue;
bool shadow;
// TODO: initialiser l'arbre autrepart
// TODO: corriger la bounding box des spheres
if (_tree == null)
{
_tree = new BBTree(Primitives);
}
IEnumerable <HitResult> hits = _tree.Hit(ray);
//IList<HitResult> hits = Primitives.Select(p =>
//{
// if (p.Intersect(ray, true, out LocalGeo geo, out float t))
// {
// return new HitResult { Primitive = p, Geo = geo, T = t };
// }
// return null;
//}).Where(h => h != null).ToList();
foreach (HitResult h in hits)
{
if (h.T < lastT)
{
lastT = h.T;
ShadingInfos si = h.Primitive.GetShading(h.Geo);
// Ambient & emission
res = si.Emission + si.Ambient;
// Phong shading
foreach (ILight light in Lights)
{
shadow = false;
RTColor lightCol;
Ray lightRay = light.GenerateRay(h.Geo, out lightCol);
foreach (IPrimitive pShadow in Primitives)
{
if (pShadow.Intersect(lightRay, false, out _, out _))
{
shadow = true;
}
}
if (!shadow)
{
res += Shading(h.Geo, si, ray, lightRay, lightCol);
}
}
// Reflection
if ((si.Specular.Red > 0 || si.Specular.Green > 0 || si.Specular.Blue > 0) && depth < MaxDepth)
{
Ray reflected = new Ray(h.Geo.Point, ray.Vector - 2.0f * RTVector.DotProduct(ray.Vector, h.Geo.Normal) * h.Geo.Normal, 1e-3f, float.MaxValue, false);
res += si.Specular * Trace(reflected, depth + 1);
}
}
}
return(res);
}
