void PhotonMap::ShootCausticsPhoton(const Vector &dir, const Vector &pi, const Color &color, Shape *shape, int depth)
{
if ( depth >= confPhotonCausticsMaximumDepth ) return;
if ( depth != 0 && shape->mMaterial->MatchesBSDFFlags(BSDF_DIFFUSE) ) {
// Diffuse material, add photon
Photon *photon = new Photon(color, dir);
AddPhoton(causticsMap, pi, photon);
} else if ( shape->mMaterial->MatchesBSDFFlags(BSDF_SPECULAR) ) {
// Specular material, continue build photon
Vector N = shape->GetNormal(pi);
for ( uint32_t i = 0; i < shape->mMaterial->BSDFs.size(); i++ ) {
BSDF *bsdf = shape->mMaterial->BSDFs[i];
if ( !bsdf->MatchesFlags(BSDFType(BSDF_SPECULAR)) ) continue;
Vector newDir;
Color matColor;
Vector *vos = NULL;
int voNum = 0;
if ( bsdf->G(-dir, vos, voNum, N, matColor, 1.f) ) {
_ASSERT(voNum > 0);
newDir = vos[0];
delete [] vos;
vos = NULL;
matColor *= shape->GetColor(pi);
if ( matColor.IsBlack() ) continue;
float dist = MAXDISTANCE;
Shape *newShape;
Vector norm = N.Dot(dir) > 0 ? -N : N;
if ( bsdf->MatchesFlags(BSDF_TRANSMISSION) ) norm = -norm;
if ( scene->FindNearest(Ray(pi + norm * EPSILON, newDir), dist, newShape) == IR_MISS )
continue;
ShootCausticsPhoton(newDir, pi + newDir * dist, color * matColor, newShape, depth + 1);
}
}
}
}
