public override IRadianceEvaluation Sample(ref Vector wo, ref IRadianceEvaluation radiance, float u0, float u1, float u2,
out BsdfSample result, BrdfType flags = BrdfType.All)
{
result = new BsdfSample()
{
};
throw new NotImplementedException();
}
public void Sample(ref Vector wo, ref Normal N, ref Normal shadeN, float u0, float u1, float u2,float u3,
out BsdfSample sample, BxDFType type = BxDFType.AllTypes) {
sample = new BsdfSample();
var fl = type;
int matchingComps = NumComponents(fl);
if (matchingComps == 0) {
sample.Pdf = 0f;
sample.Wi = Vector.Zero;
sample.Spectrum = new RgbSpectrum(0f).ToArray();
}
int which = (int)Math.Min((u0 * matchingComps),
matchingComps - 1);
BxDFBase bxdf = null;
int count = which;
for (int i = 0; i < Bxdfs.Length; ++i)
if (Bxdfs[i].Type.HasFlag(fl))
if (count-- == 0) {
bxdf = Bxdfs[i];
break;
}
Vector wi = new Vector();
var pdf = 0f;
bxdf.Sample(ref wo, ref N, ref shadeN, u1, u2, u3, out sample, type);
wi = sample.Wi;
pdf = sample.Pdf;
var sampled = bxdf.Type;
if (pdf > 0f && pdf < MathLab.Epsilon) sample.Spectrum = new float[3]{0f,0f,0f};
//if (sampledTy != null) sampledType = bxdf.Type;
//wiW = LocalToWorld(wi);
if ((!bxdf.Type.HasFlag(BxDFType.Specular)) && matchingComps > 1) {
for (int i = 0; i < Bxdfs.Length; ++i) {
if (Bxdfs[i] != bxdf && (Bxdfs[i].Type.HasFlag(fl)))
pdf += Bxdfs[i].Pdf(ref wo, ref wi, fl);
}
}
if (matchingComps > 1) pdf /= matchingComps;
// Compute value of BSDF for sampled direction
if (bxdf.Type.HasFlag(BxDFType.Specular))
//if ((bxdf.Type & BxDFType.BSDF_SPECULAR) == 0)
{
var f = RgbSpectrum.ZeroSpectrum();
if ((Vector.Dot(ref N,ref wi)) * Vector.Dot(ref N, ref wo) > 0f)
// ignore BTDFs
{
fl = fl & ~BxDFType.Transmission;
}
else
// ignore BRDFs
fl = (fl & ~BxDFType.Reflection);
for (int i = 0; i < Bxdfs.Length; ++i)
if ((Bxdfs[i].Type.HasFlag(fl)))
f += new RgbSpectrum(Bxdfs[i].Eval(ref wo, ref wi, ref N));
sample.Spectrum = (f/pdf).ToArray();
}
}
public IRadianceEvaluation Sample(ref Vector wo, ref IRadianceEvaluation radiance, float u0, float u1, float u2, out BsdfSample result, BrdfType flags = BrdfType.All)
{
float selPdf;
BaseBsdf bxdf = GetBsdf(out selPdf, flags);
if (bxdf == null)
{
result = new BsdfSample();
return ColorManager.Instance.ZeroRadiance();
}
Vector wo1 = bxdf.WorldToLocal(ref wo);
var r = bxdf.Sample(ref wo1, ref radiance, u0, u1, u2, out result, flags);
result.DirectPdf *= selPdf;
result.OutgoingDirection = bxdf.LocalToWorld(ref result.OutgoingDirection);
return r;
/*Vector wi = new Vector();
var wiW = Vector.Zero;
var pdf = 0f;
bool specularBounce;
if (pdf > 0f && pdf < MathLab.Epsilon) return ColorManager.Instance.ZeroRadiance();
if (flags != BrdfType.All ) flags = bxdf.Type;
wiW = bxdf.LocalToWorld(ref wi);
if ((!bxdf.Type.Has(BrdfType.Specular)) && matchingComps > 1)
{
for (int i = 0; i < bxdfs.Count; ++i)
{
if (bxdfs[i] != bxdf &&bxdfs[i].Type.Has(flags))
pdf += bxdfs[i].Pdf(scene, ref wo);
}
}
if (matchingComps > 1) pdf /= matchingComps;
if (bxdf.Type.Has(BrdfType.Specular))
{
var f = ColorManager.Instance.ZeroRadiance();
if ((Vector.Dot(ref wiW , ref bxdf.Ng)) * Vector.Dot(ref wo1 ,ref bxdf.Ng) > 0f)
// ignore BTDFs
{
flags = flags & ~BrdfType.Refractive;
}
else
// ignore BRDFs
flags = flags & ~BrdfType.Reflection;
float cosp, rwp;
for (int i = 0; i < bxdfs.Count; ++i)
if (bxdfs[i].Type.Has(flags))
f.Add(bxdfs[i].Evaluate(scene, ref wo, Vector.Dot(ref wiW, ref bxdf.Ng), out cosp, out rwp));
f.Div(pdf);
}
return f;*/
}
public abstract void Sample(ref Vector wo, ref Normal N, ref Normal shadeN, float u0, float u1, float u2,out BsdfSample sample,BxDFType type = BxDFType.AllTypes);
