fix point sources in the RTRT preview

include/mitsuba/render/preview.h

@@ -31,10 +31,12 @@ MTS_NAMESPACE_BEGIN
 class MTS_EXPORT_RENDER PreviewWorker : public WorkProcessor {
 public:
 	inline PreviewWorker(int blockSize, Point cameraO, Vector cameraTL, 
-		Vector cameraDx, Vector cameraDy, const VPL &vpl, Float minDist, bool coherent) 
+		Vector cameraDx, Vector cameraDy, const VPL &vpl, Float minDist, bool coherent,
+		bool diffuseSources, bool diffuseReceivers) 
 		: m_blockSize(blockSize), m_cameraO(cameraO), m_cameraTL(cameraTL),
 		m_cameraDx(cameraDx), m_cameraDy(cameraDy), m_vpl(vpl), 
-		m_minDist(minDist), m_coherent(coherent) {
+		m_minDist(minDist), m_coherent(coherent), m_diffuseSources(diffuseSources),
+		m_diffuseReceivers(diffuseReceivers) {
 	}
 
 	void processIncoherent(const WorkUnit *workUnit, WorkResult *workResult, 
@@ -68,6 +70,7 @@ private:
 	Float m_minDist;
 	const std::vector<const Shape *> *m_shapes;
 	bool m_coherent;
+	bool m_diffuseSources, m_diffuseReceivers;
 };
 
 MTS_NAMESPACE_END

src/libhw/vpl.cpp

@@ -192,7 +192,7 @@ void VPLShaderManager::setVPL(const VPL &vpl) {
 	for (int i=1; i<=sampleCount; ++i) {
 		Vector dir;
 		Point2 seed(i*invSampleCount, radicalInverse(2, i)); // Hammersley seq.
-		if (vpl.type == ELuminaireVPL && vpl.luminaire->getType() & Luminaire::EOnSurface)
+		if (vpl.type == ESurfaceVPL || vpl.luminaire->getType() & Luminaire::EOnSurface)
 			dir = vpl.its.shFrame.toWorld(squareToHemispherePSA(seed));
 		else
 			dir = squareToSphere(seed);

src/librender/preview.cpp

@@ -108,9 +108,10 @@ void PreviewWorker::processIncoherent(const WorkUnit *workUnit, WorkResult *work
 				EmissionRecord eRec(m_vpl.luminaire, 
 					ShapeSamplingRecord(m_vpl.its.p, m_vpl.its.shFrame.n), toIts);
 				eRec.type = EmissionRecord::EPreview;
-				value += m_vpl.P * bsdfVal * m_vpl.luminaire->f(eRec) * 
+				value += m_vpl.P * bsdfVal * m_vpl.luminaire->f(eRec) 
-					((m_vpl.luminaire->getType() == Luminaire::EOnSurface ? 
+					* ((m_vpl.luminaire->getType() & Luminaire::EOnSurface ?
-						(Float) 1 : dot(m_vpl.its.shFrame.n, toIts)) / (length*length));
+					dot(m_vpl.its.shFrame.n, toIts) : (Float) 1)
+					/ (length*length));
 			}
 			block->setPixel(pos++, value);
 		}
@@ -178,7 +179,7 @@ void PreviewWorker::processCoherent(const WorkUnit *workUnit, WorkResult *workRe
 	bool diffuseVPL = false, vplOnSurface = false;
 	Spectrum vplWeight;
 
-	if (m_vpl.type == ESurfaceVPL && m_vpl.its.shape->getBSDF()->getType() == BSDF::EDiffuseReflection) {
+	if (m_vpl.type == ESurfaceVPL && (m_diffuseSources || m_vpl.its.shape->getBSDF()->getType() == BSDF::EDiffuseReflection)) {
 		diffuseVPL = true;
 		vplOnSurface = true;
 		vplWeight = m_vpl.its.shape->getBSDF()->getDiffuseReflectance(m_vpl.its) * m_vpl.P / M_PI;
@@ -324,7 +325,7 @@ void PreviewWorker::processCoherent(const WorkUnit *workUnit, WorkResult *workRe
 					/* Fast path */
 					direct[idx] = (bsdf->getDiffuseReflectance(its) * vplWeight)
 						* (std::max((Float) 0.0f, dot(wo, its.shFrame.n))
-						* (vplOnSurface ? std::max(cosThetaLight.f[idx], (Float) 0.0f) * INV_PI : 0.0f)
+						* (vplOnSurface ? std::max(cosThetaLight.f[idx], (Float) 0.0f) * INV_PI : 1.0f)
 						* invLengthSquared.f[idx]);
 				} else {
 					wi.x = -primRay4.d[0].f[idx];
@@ -355,7 +356,7 @@ void PreviewWorker::processCoherent(const WorkUnit *workUnit, WorkResult *workRe
 						}
 					}
 
-					if (EXPECT_TAKEN(ctLight > 0)) {
+					if (EXPECT_TAKEN(ctLight >= 0)) {
 						direct[idx] = (bsdf->fCos(BSDFQueryRecord(its, wo)) * vplWeight
 							* ((vplOnSurface ? std::max(ctLight, (Float) 0.0f) : 1.0f) * invLengthSquared.f[idx]));
 					} else {
@@ -402,7 +403,8 @@ void PreviewWorker::processCoherent(const WorkUnit *workUnit, WorkResult *workRe
 
 ref<WorkProcessor> PreviewWorker::clone() const {
 	return new PreviewWorker(m_blockSize, m_cameraO, m_cameraTL, 
-		m_cameraDx, m_cameraDy, m_vpl, m_minDist, m_coherent);
+		m_cameraDx, m_cameraDy, m_vpl, m_minDist, m_coherent,
+		m_diffuseSources, m_diffuseReceivers);
 }
 
 MTS_IMPLEMENT_CLASS(PreviewWorker, false, WorkProcessor)

src/qtgui/preview.cpp

@@ -545,10 +545,10 @@ void PreviewThread::rtrtRenderVPL(PreviewQueueEntry &target, const VPL &vpl) {
 	for (int i=1; i<=sampleCount; ++i) {
 		Vector dir;
 		Point2 seed(i*invSampleCount, radicalInverse(2, i)); // Hammersley seq.
-		if (vpl.type == ELuminaireVPL && vpl.luminaire->getType() == Luminaire::EDeltaPosition)
+		if (vpl.type == ESurfaceVPL || vpl.luminaire->getType() & Luminaire::EOnSurface)
-			dir = squareToSphere(seed);
-		else
 			dir = vpl.its.shFrame.toWorld(squareToHemispherePSA(seed));
+		else
+			dir = squareToSphere(seed);
 		ray.setDirection(dir);
 
 		if (m_context->scene->rayIntersect(ray, its)) {
@@ -578,7 +578,9 @@ void PreviewThread::rtrtRenderVPL(PreviewQueueEntry &target, const VPL &vpl) {
 	m_previewProc->configure(vpl, minDist, jitter, 
 		m_accumBuffer ? m_accumBuffer->getBitmap() : NULL, 
 		target.buffer->getBitmap(), 
-		m_context->previewMethod == ERayTraceCoherent);
+		m_context->previewMethod == ERayTraceCoherent,
+		m_context->diffuseSources,
+		m_context->diffuseReceivers);
 	m_mutex->unlock();
 
 	ref<Scheduler> sched = Scheduler::getInstance();

src/qtgui/preview_proc.cpp

@@ -72,7 +72,8 @@ void PreviewProcess::processResult(const WorkResult *result, bool cancelled) {
 }
 
 void PreviewProcess::configure(const VPL &vpl, Float minDist, const Point2 &jitter, 
-		const Bitmap *source, Bitmap *target, bool coherent) {
+		const Bitmap *source, Bitmap *target, bool coherent, bool diffuseSources,
+		bool diffuseReceivers) {
 	BlockedImageProcess::init(m_film->getCropOffset(), m_film->getCropSize(), m_blockSize);
 	m_source = source;
 	m_target = target;
@@ -80,6 +81,8 @@ void PreviewProcess::configure(const VPL &vpl, Float minDist, const Point2 &jitt
 	m_vpl = &vpl;
 	m_minDist = minDist;
 	m_coherent = coherent;
+	m_diffuseSources = diffuseSources;
+	m_diffuseReceivers = diffuseReceivers;
 
 	/* It is not necessary to shoot normalized rays. Instead, interpolate: 
 	   here, we generate the upper left corner ray as well as the 
@@ -104,7 +107,8 @@ void PreviewProcess::configure(const VPL &vpl, Float minDist, const Point2 &jitt
 
 ref<WorkProcessor> PreviewProcess::createWorkProcessor() const {
 	return new PreviewWorker(m_blockSize, m_cameraO, m_cameraTL,
-		m_cameraDx, m_cameraDy, *m_vpl, m_minDist, m_coherent);
+		m_cameraDx, m_cameraDy, *m_vpl, m_minDist, m_coherent,
+		m_diffuseSources, m_diffuseReceivers);
 }
 
 

src/qtgui/preview_proc.h

@@ -17,7 +17,8 @@ public:
 	PreviewProcess(const Scene *scene, int sceneResID, int blockSize);
 
 	void configure(const VPL &vpl, Float minDist, const Point2 &jitter, 
-		const Bitmap *source, Bitmap *target, bool coherent); 
+		const Bitmap *source, Bitmap *target, bool coherent,
+		bool diffuseSources, bool diffuseReceivers); 
 	inline int getRayCount() const { return m_numRays; }
 	inline const Scene *getScene() const { return m_scene; }
 
@@ -42,6 +43,8 @@ private:
 	const VPL *m_vpl;
 	Float m_minDist;
 	bool m_coherent;
+	bool m_diffuseSources;
+	bool m_diffuseReceivers;
 };
 
 #endif /* __PREVIEW_PROC_H */