public override Color Eval(Normal normal, Vec inDir, Vec outDir, Vec2D uv)
{
float thetaIn = MathF.Acos(Utility.NormalizedDot(normal.ToVec(), inDir));
float thetaOut = MathF.Acos(Utility.NormalizedDot(normal.ToVec(), outDir));
if (MathF.Abs(thetaIn - thetaOut) < this.thresholdAngleRad)
return this.pigment.getColor(uv);
else
return new Color(0f, 0f, 0f);
}
public override Ray scatterRay(PCG r, Vec incomingDir, Point interactionPoint, Normal normal, int depth)
{
Vec rayDir = new Vec(incomingDir.x, incomingDir.y, incomingDir.z).Normalize();
Vec normalVec = normal.ToVec().Normalize();
float dotProd = normalVec * rayDir;
return new Ray(
origin: interactionPoint,
dir: rayDir - normalVec * 2f * dotProd,
tm: 1e-5f,
tM: Single.PositiveInfinity,
dep: depth
);
}