mingzailao
/
mitsuba
mirror of https://github.com/Quartenia/mitsuba.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

this fixes a ptracer path depth inconsistency wrt. other integrators and fully implements the adjoint BSDF for shading normals everywhere

metadata
Wenzel Jakob 2010-11-25 00:30:10 +01:00
parent 0815910bc8
commit 946611320a
1 changed files with 19 additions and 6 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

25
src/integrators/path/ptracer_proc.cpp
View File

@ -81,10 +81,10 @@ void CaptureParticleWorker::handleSurfaceInteraction(int, bool,
return;
const BSDF *bsdf = its.shape->getBSDF();
Vector d = cameraPosition - its.p;
Float dist = d.length(); d /= dist;
Vector wo = cameraPosition - its.p;
Float dist = wo.length(); wo /= dist;
BSDFQueryRecord bRec(its, its.toLocal(d));
BSDFQueryRecord bRec(its, its.toLocal(wo));
bRec.quantity = EImportance;
Float importance;
@ -93,10 +93,23 @@ void CaptureParticleWorker::handleSurfaceInteraction(int, bool,
else
importance = 1/m_camera->areaDensity(screenSample);
Vector wi = its.toWorld(its.wi);
/* Prevent light leaks due to the use of shading normals -- [Veach, p. 158] */
Float wiDotGeoN = dot(its.geoFrame.n, wi),
woDotGeoN = dot(its.geoFrame.n, wo);
if (wiDotGeoN * Frame::cosTheta(bRec.wi) <= 0 ||
woDotGeoN * Frame::cosTheta(bRec.wo) <= 0)
return;
/* Adjoint BSDF for shading normals -- [Veach, p. 155] */
Float correction = std::abs(
(Frame::cosTheta(bRec.wi) * woDotGeoN)/
(Frame::cosTheta(bRec.wo) * wiDotGeoN));
/* Compute Le * importance and store it in an accumulation buffer */
Ray ray(its.p, d, 0, dist, its.time);
Ray ray(its.p, wo, 0, dist, its.time);
Spectrum sampleVal = weight * bsdf->fCos(bRec)
* m_scene->getAttenuation(ray) * importance;
* m_scene->getAttenuation(ray) * (importance * correction);
m_workResult->splat(screenSample, sampleVal, m_filter);
}
@ -200,7 +213,7 @@ void CaptureParticleProcess::bindResource(const std::string &name, int id) {
}
ref<WorkProcessor> CaptureParticleProcess::createWorkProcessor() const {
return new CaptureParticleWorker(m_maxDepth, m_multipleScattering,
return new CaptureParticleWorker(m_maxDepth-1, m_multipleScattering,
m_rrDepth);
}