transparent BSDF

src/bsdfs/transparent.cpp

@@ -0,0 +1,87 @@
+#include <mitsuba/render/bsdf.h>
+
+MTS_NAMESPACE_BEGIN
+
+/**
+ * Ideal transparent BRDF
+ */
+class Transparent : public BSDF {
+public:
+	Transparent(const Properties &props) 
+		: BSDF(props) {
+		m_transmission = props.getSpectrum("transmission", Spectrum(0.8f));
+		m_componentCount = 1;
+		m_type = new unsigned int[m_componentCount];
+		m_type[0] = EDeltaTransmission;
+		m_combinedType = m_type[0];
+		m_usesRayDifferentials = false;
+	}
+
+	Transparent(Stream *stream, InstanceManager *manager) 
+		: BSDF(stream, manager) {
+		m_transmission = Spectrum(stream);
+		m_componentCount = 1;
+		m_type = new unsigned int[m_componentCount];
+		m_type[0] = EDeltaTransmission;
+		m_combinedType = m_type[0];
+		m_usesRayDifferentials = false;
+	}
+
+	virtual ~Transparent() {
+		delete[] m_type;
+	}
+
+	void serialize(Stream *stream, InstanceManager *manager) const {
+		BSDF::serialize(stream, manager);
+
+		m_transmission.serialize(stream);
+	}
+
+	Spectrum getDiffuseReflectance(const Intersection &its) const {
+		return Spectrum(0.0f);
+	}
+	
+	Spectrum f(const BSDFQueryRecord &bRec) const {
+		return Spectrum(0.0f);
+	}
+
+	Float pdf(const BSDFQueryRecord &bRec) const {
+		return 0.0f;
+	}
+
+	inline void transmit(const Vector &wi, Vector &wo) const {
+		wo = Vector(wi.x, wi.y, -wi.z);
+	}
+
+	inline Spectrum sample(BSDFQueryRecord &bRec) const {
+		Float pdf;
+		return Transparent::sample(bRec, pdf);
+	}
+
+	Spectrum sample(BSDFQueryRecord &bRec, Float &pdf) const {
+		if (!(bRec.typeMask & m_combinedType))
+			return Spectrum(0.0f);
+		transmit(bRec.wi, bRec.wo);
+		bRec.sampledComponent = 0;
+		bRec.sampledType = EDeltaTransmission;
+		pdf = std::abs(Frame::cosTheta(bRec.wo));
+		return m_transmission;
+	}
+
+	Float pdfDelta(const BSDFQueryRecord &bRec) const {
+		return std::abs(Frame::cosTheta(bRec.wo));
+	}
+	
+	Spectrum fDelta(const BSDFQueryRecord &bRec) const {
+		return m_transmission;
+	}
+
+	MTS_DECLARE_CLASS()
+protected:
+	Spectrum m_transmission;
+};
+
+
+MTS_IMPLEMENT_CLASS_S(Transparent, false, BSDF)
+MTS_EXPORT_PLUGIN(Transparent, "Transparent BRDF");
+MTS_NAMESPACE_END