public override Bsdf GetBsdf(DifferentialGeometry dgGeom, DifferentialGeometry dgShading)
{
// Allocate _BSDF_, possibly doing bump mapping with _bumpMap_
var dgs = (_bumpMap != null)
? Bump(_bumpMap, dgGeom, dgShading)
: dgShading;
var bsdf = new Bsdf(dgs, dgGeom.Normal);
// Evaluate textures for _MatteMaterial_ material and allocate BRDF
Spectrum r = Spectrum.Clamp(_kd.Evaluate(dgs));
float sig = MathUtility.Clamp(_sigma.Evaluate(dgs), 0.0f, 90.0f);
if (!r.IsBlack)
{
if (sig == 0.0f)
{
bsdf.Add(new Lambertian(r));
}
else
{
bsdf.Add(new OrenNayar(r, sig));
}
}
return(bsdf);
}
public void ComputeScatteringFunctions(SurfaceInteraction inter, bool allowMultipleLobes)
{
var r = Diffuse.Clamp();
//TODO sigma -> Oren-Nayar
inter.Bsdf = new BSDF(inter);
inter.Bsdf.Add(new LambertianReflection(r));
}