done with the smooth conductor, started working on the rough dielectric

data/ior/Cu.eta.spd

@@ -2,6 +2,7 @@
 # ;  Optical constants for Cu
 # ;  
 # ;    Lambda (A)            n            k
+# ;-----------------------------------------
 302.400421 1.380000
 306.133759 1.358438
 309.960449 1.340000

data/ior/Cu.k.spd

@@ -3,7 +3,6 @@
 # ;  
 # ;    Lambda (A)            n            k
 # ;-----------------------------------------
-298.757050 1.662125
 302.400421 1.687000
 306.133759 1.703313
 309.960449 1.720000

data/tests/test_bsdf.xml

@@ -24,4 +24,7 @@
 			<rgb name="transmittance" value="0 .5 0"/>
 		</bsdf>
 	</bsdf>
+
+	<!-- Test the conductor model -->
+	<bsdf type="conductor"/>
 </scene>

doc/format.tex

@@ -127,6 +127,7 @@ Passing strings is straightforward:
 <string name="stringProperty" value="This is a string"/>
 \end{xml}
 \subsubsection{Color spectra}
+\label{sec:format-spectra}
 Depending on the compilation flags of Mitsuba (see \secref{compiling-flags} for
 details), the renderer internally either represents colors using discretized color spectra
 (when \texttt{SPECTRUM\_SAMPLES} is set to a value other than 3), or it

doc/macros.sty

@@ -3,6 +3,7 @@
 \newcommand{\figref}[1]{\mbox{Figure~\ref{fig:#1}}}
 \newcommand{\secref}[1]{\mbox{Section~\ref{sec:#1}}}
 \newcommand{\lstref}[1]{\mbox{Listing~\ref{lst:#1}}}
+\newcommand{\tblref}[1]{\mbox{Table~\ref{tbl:#1}}}
 \newcommand{\code}[1]{\texttt{#1}}
 
 % Macros that are used in the plugin documentation

doc/main.bib

@@ -21,3 +21,10 @@
 	year      = {2005},
 	publisher = {AK Peters, Ltd.}
 }
+
+@book{Palik1998Handbook,
+	title     = {Handbook of optical constants of solids},
+	author    = {Palik, E.D. and Ghosh, G.},
+	year      = {1998},
+	publisher = {Academic press}
+}

include/mitsuba/core/util.h

@@ -453,14 +453,14 @@ extern MTS_EXPORT_CORE Float fresnel(Float cosThetaI, Float etaExt,
  * Calculates the unpolarized fresnel reflection coefficient on
  * an interface to a conductor.
  *
- * \param cosTheta
+ * \param cosThetaI
  * 		Cosine of the angle between the normal and the incident ray
  * \param eta
- * 		Relative refractive index (per wavelength)
+ * 		Real refractive index (wavelength-dependent)
  * \param k
- * 		Absorption coefficient (per wavelength)
+ * 		Imaginary refractive index (wavelength-dependent)
  */
-extern MTS_EXPORT_CORE Spectrum fresnelConductor(Float cosTheta, 
+extern MTS_EXPORT_CORE Spectrum fresnelConductor(Float cosThetaI, 
 		const Spectrum &eta, const Spectrum &k);
 
 /*! @} */

src/bsdfs/SConscript

@@ -6,7 +6,7 @@ plugins += env.SharedLibrary('conductor', ['conductor.cpp'])
 plugins += env.SharedLibrary('diffuse', ['diffuse.cpp'])
 #plugins += env.SharedLibrary('plastic', ['plastic.cpp'])
 
-#plugins += env.SharedLibrary('roughdielectric', ['roughdielectric.cpp'])
+plugins += env.SharedLibrary('roughdielectric', ['roughdielectric.cpp'])
 #plugins += env.SharedLibrary('roughconductor', ['roughconductor.cpp'])
 #plugins += env.SharedLibrary('roughdiffuse', ['roughdiffuse.cpp'])
 #plugins += env.SharedLibrary('roughplastic', ['roughplastic.cpp'])

src/bsdfs/coating.cpp

@@ -21,7 +21,7 @@
 
 MTS_NAMESPACE_BEGIN
 
-/*! \plugin{varnish}{Smooth varnish layer}
+/*! \plugin{coating}{Smooth coating layer}
  *
  * \parameters{
  *     \parameter{intIOR}{\Float}{Interior index of refraction \default{1.5046}}

src/bsdfs/conductor.cpp

@@ -18,13 +18,75 @@
 
 #include <mitsuba/render/bsdf.h>
 #include <mitsuba/render/consttexture.h>
-#include "ior.h"
+#include <mitsuba/core/fresolver.h>
 
 MTS_NAMESPACE_BEGIN
 
 /*! \plugin{conductor}{Smooth conductor}
+ * \parameters{
+ *     \parameter{preset}{\String}{Name of a material preset, see \tblref{conductor-iors}.\!\default{\texttt{Cu} / copper}}
+ *     \parameter{eta}{\Spectrum}{Real part of the material's index of refraction \default{based on the value of \texttt{preset}}}
+ *     \parameter{k}{\Spectrum}{Imaginary part of the material's index of refraction, also known as absorption coefficient.
+ *                              \default{based on the value of \texttt{preset}}}
+ *     \lastparameter{specular\showbreak Reflectance}{\Spectrum\Or\Texture}{Optional
+ *         factor used to modulate the reflectance component\default{1.0}}
+ * }
+ * \renderings{
+ *     \rendering{Measured copper material (the default)}{bsdf_conductor_copper.jpg}
+ *     \rendering{Measured gold material (\lstref{conductor-gold})}{bsdf_conductor_gold.jpg}
+ * }
+ 
+ * This plugin implements a perfectly smooth interface to a conducting material, 
+ * such as a metal. For a similar model that instead describes a rough surface 
+ * microstructure, take a look at the seperately available 
+ * \pluginref{roughconductor} plugin.
+
+ * In contrast to dielectric materials, conductors do not transmit 
+ * any light. Their index of refraction is complex-valued and tends to undergo
+ * considerable changes throughout the visible color spectrum. 
+ * 
+ * To faciliate the tedious task of specifying spectrally-varying index of 
+ * refraction information, Mitsuba ships with a set of measured data for a 
+ * several materials, where visible-spectrum information was publicly available\footnote{
+ *   These index of refraction values are identical to the data distributed with PBRT. 
+ *   They are originally from the Luxpop database (\url{www.luxpop.com}) and 
+ *   are based on data by Palik et al. \cite{Palik1998Handbook} and measurements 
+ *   of atomic scattering factors made by the Center For X-Ray Optics (CXRO) 
+ *   at Berkeley and the Lawrence Livermore National Laboratory (LLNL).
+ * }. 
+ * 
+ * Note that \tblref{conductor-iors} also includes several popular optical coatings, which are
+ * not actually conductors. These materials can also be used with this plugin,
+ * though note that the plugin will ignore any refraction component that the actual 
+ * material might have had.
+ * The table also contains a few birefingent materials, which are split into
+ * separate measurements correponding to their two indices of 
+ * refraction (named ``ordinary'' and ``extraordinary ray'').
  *
- * \begin{table}
+ * When using this plugin, you should compile Mitsuba with support for spectral 
+ * renderings to get the most accurate results. While it also works in RGB mode, 
+ * the computations will be much more approximate in this case.
+ *
+ * \begin{xml}[caption=Material configuration for a smooth conductor with measured gold data, label=lst:conductor-gold]
+ * <shape type="...">
+ *     <bsdf type="conductor">
+ *         <string name="preset" value="Au"/>
+ *     </bsdf>
+ * <shape>
+ * \end{xml}
+ * \vspace{5mm}
+ * It is also possible to load spectrally varying index of refraction data from 
+ * two external files (see \secref{format-spectra} for details on the file format):
+ * \begin{xml}[caption=Rendering a smooth conductor with custom data]
+ * <shape type="...">
+ *     <bsdf type="conductor">
+ *         <spectrum name="eta" filename="conductorIOR.eta.spd"/>
+ *         <spectrum name="k" filename="conductorIOR.k.spd"/>
+ *     </bsdf>
+ * <shape>
+ * \end{xml}
+ * \vspace{1.5cm}
+ * \begin{table}[hb!]
  * \centering
  * \scriptsize
  * \begin{tabular}{>{\ttfamily}llp{1mm}>{\ttfamily}ll}
@@ -55,24 +117,33 @@ MTS_NAMESPACE_BEGIN
  * \bottomrule
  * \end{tabular}
  * \caption{
- *     \label{tbl:dielectric-iors}
+ *     \label{tbl:conductor-iors}
  *      This table lists all supported material names that can be passed into the
- *      \pluginref{conductor} plugin. In most cases, there are two separate
+ *      \pluginref{conductor} plugin. Note that some of them are not actually 
- *       measurements of the same material made using different approaches.
+ *      conductors---this is not a problem, they can be used regardless (though only
+ *      the reflection component and no transmission will be simulated).
+ *      In most cases, there are multiple entries for each material, which 
+ *      represent different measurements.
  * }
  * \end{table}
- **
  */
 class SmoothConductor : public BSDF {
 public:
 	SmoothConductor(const Properties &props) : BSDF(props) {
+		ref<FileResolver> fResolver = Thread::getThread()->getFileResolver();
+
 		m_specularReflectance = new ConstantSpectrumTexture(
 			props.getSpectrum("specularReflectance", Spectrum(1.0f)));
 
 		std::string preset = props.getString("preset", "Cu");
+		Spectrum presetEta, presetK;
+		presetEta.fromContinuousSpectrum(InterpolatedSpectrum(
+			fResolver->resolve("data/ior/" + preset + ".eta.spd")));
+		presetK.fromContinuousSpectrum(InterpolatedSpectrum(
+			fResolver->resolve("data/ior/" + preset + ".k.spd")));
 
-		//m_eta = props.getSpectrum("eta", presetEta);
+		m_eta = props.getSpectrum("eta", presetEta);
-//		m_k = props.getSpectrum("k", presetK);
+		m_k = props.getSpectrum("k", presetK);
 
 		m_components.push_back(EDeltaReflection | EFrontSide);
 		m_usesRayDifferentials = false;
@@ -106,20 +177,63 @@ public:
 		}
 	}
 
-	Spectrum sample(BSDFQueryRecord &bRec, const Point2 &sample) const {
+	/// Reflection in local coordinates
-		return Spectrum(0.0f);
+	inline Vector reflect(const Vector &wi) const {
+		return Vector(-wi.x, -wi.y, wi.z);
 	}
 
 	Spectrum eval(const BSDFQueryRecord &bRec, EMeasure measure) const {
-		return Spectrum(0.0f);
+		bool sampleReflection   = (bRec.typeMask & EDeltaReflection)
-	}
+				&& (bRec.component == -1 || bRec.component == 0);
 
-	Spectrum sample(BSDFQueryRecord &bRec, Float &pdf, const Point2 &sample) const {
+		if (!sampleReflection || measure != EDiscrete ||
-		return Spectrum(0.0f);
+			Frame::cosTheta(bRec.wi) <= 0 ||
+			Frame::cosTheta(bRec.wo) <= 0)
+			return Spectrum(0.0f);
+
+		return m_specularReflectance->getValue(bRec.its) *
+			fresnelConductor(Frame::cosTheta(bRec.wi), m_eta, m_k);
 	}
 
 	Float pdf(const BSDFQueryRecord &bRec, EMeasure measure) const {
-		return 0.0f;
+		bool sampleReflection   = (bRec.typeMask & EDeltaReflection)
+				&& (bRec.component == -1 || bRec.component == 0);
+		if (!sampleReflection || measure != EDiscrete || 
+			Frame::cosTheta(bRec.wi) <= 0 ||
+			Frame::cosTheta(bRec.wo) <= 0)
+			return 0.0f;
+		return 1.0f;
+	}
+
+	Spectrum sample(BSDFQueryRecord &bRec, const Point2 &sample) const {
+		bool sampleReflection   = (bRec.typeMask & EDeltaReflection)
+				&& (bRec.component == -1 || bRec.component == 0);
+		
+		if (!sampleReflection || Frame::cosTheta(bRec.wi) <= 0)
+			return Spectrum(0.0f);
+
+		bRec.sampledComponent = 0;
+		bRec.sampledType = EDeltaReflection;
+		bRec.wo = reflect(bRec.wi);
+
+		return m_specularReflectance->getValue(bRec.its) *
+			fresnelConductor(Frame::cosTheta(bRec.wi), m_eta, m_k);
+	}
+
+	Spectrum sample(BSDFQueryRecord &bRec, Float &pdf, const Point2 &sample) const {
+		bool sampleReflection   = (bRec.typeMask & EDeltaReflection)
+				&& (bRec.component == -1 || bRec.component == 0);
+		
+		if (!sampleReflection || Frame::cosTheta(bRec.wi) <= 0)
+			return Spectrum(0.0f);
+
+		bRec.sampledComponent = 0;
+		bRec.sampledType = EDeltaReflection;
+		bRec.wo = reflect(bRec.wi);
+		pdf = 1;
+
+		return m_specularReflectance->getValue(bRec.its) *
+			fresnelConductor(Frame::cosTheta(bRec.wi), m_eta, m_k);
 	}
 
 	std::string toString() const {

src/bsdfs/dielectric.cpp

@@ -196,6 +196,54 @@ public:
 		return Vector(-eta*wi.x, -eta*wi.y, cosThetaT);
 	}
 
+	Spectrum eval(const BSDFQueryRecord &bRec, EMeasure measure) const {
+		bool sampleReflection   = (bRec.typeMask & EDeltaReflection)
+				&& (bRec.component == -1 || bRec.component == 0);
+		bool sampleTransmission = (bRec.typeMask & EDeltaTransmission)
+				&& (bRec.component == -1 || bRec.component == 1);
+		bool reflection = Frame::cosTheta(bRec.wo) * Frame::cosTheta(bRec.wi) > 0;
+		
+		if ((reflection && !sampleReflection) || 
+		   (!reflection && !sampleTransmission) || measure != EDiscrete)
+			return Spectrum(0.0f);
+
+		Float fr = fresnel(Frame::cosTheta(bRec.wi), m_extIOR, m_intIOR);
+
+		if (reflection) {
+			return m_specularReflectance->getValue(bRec.its) * fr;
+		} else {
+			Float etaI = m_extIOR, etaT = m_intIOR;
+			bool entering = Frame::cosTheta(bRec.wi) > 0.0f;
+			if (!entering)
+				std::swap(etaI, etaT);
+
+			Float factor = (bRec.quantity == ERadiance) 
+				? (etaI*etaI) / (etaT*etaT) : 1.0f;
+
+			return m_specularTransmittance->getValue(bRec.its)  * factor * (1 - fr);
+		}
+	}
+
+	Float pdf(const BSDFQueryRecord &bRec, EMeasure measure) const {
+		bool sampleReflection   = (bRec.typeMask & EDeltaReflection)
+				&& (bRec.component == -1 || bRec.component == 0);
+		bool sampleTransmission = (bRec.typeMask & EDeltaTransmission)
+				&& (bRec.component == -1 || bRec.component == 1);
+		bool reflection = Frame::cosTheta(bRec.wo)
+			* Frame::cosTheta(bRec.wi) > 0;
+
+		if ((reflection && !sampleReflection) || 
+		   (!reflection && !sampleTransmission) || measure != EDiscrete)
+			return 0.0f;
+
+		if (sampleTransmission && sampleReflection) {
+			Float Fr = fresnel(Frame::cosTheta(bRec.wi), m_extIOR, m_intIOR);
+			return reflection ? Fr : (1 - Fr);
+		} else {
+			return 1.0f;
+		}
+	}
+
 	Spectrum sample(BSDFQueryRecord &bRec, const Point2 &sample) const {
 		bool sampleReflection   = (bRec.typeMask & EDeltaReflection)
 				&& (bRec.component == -1 || bRec.component == 0);
@@ -278,54 +326,6 @@ public:
 		}
 	}
 
-	Spectrum eval(const BSDFQueryRecord &bRec, EMeasure measure) const {
-		bool sampleReflection   = (bRec.typeMask & EDeltaReflection)
-				&& (bRec.component == -1 || bRec.component == 0);
-		bool sampleTransmission = (bRec.typeMask & EDeltaTransmission)
-				&& (bRec.component == -1 || bRec.component == 1);
-		bool reflection = Frame::cosTheta(bRec.wo) * Frame::cosTheta(bRec.wi) > 0;
-		
-		if ((reflection && !sampleReflection) || 
-		   (!reflection && !sampleTransmission) || measure != EDiscrete)
-			return Spectrum(0.0f);
-
-		Float fr = fresnel(Frame::cosTheta(bRec.wi), m_extIOR, m_intIOR);
-
-		if (reflection) {
-			return m_specularReflectance->getValue(bRec.its) * fr;
-		} else {
-			Float etaI = m_extIOR, etaT = m_intIOR;
-			bool entering = Frame::cosTheta(bRec.wi) > 0.0f;
-			if (!entering)
-				std::swap(etaI, etaT);
-
-			Float factor = (bRec.quantity == ERadiance) 
-				? (etaI*etaI) / (etaT*etaT) : 1.0f;
-
-			return m_specularTransmittance->getValue(bRec.its)  * factor * (1 - fr);
-		}
-	}
-
-	Float pdf(const BSDFQueryRecord &bRec, EMeasure measure) const {
-		bool sampleReflection   = (bRec.typeMask & EDeltaReflection)
-				&& (bRec.component == -1 || bRec.component == 0);
-		bool sampleTransmission = (bRec.typeMask & EDeltaTransmission)
-				&& (bRec.component == -1 || bRec.component == 1);
-		bool reflection = Frame::cosTheta(bRec.wo)
-			* Frame::cosTheta(bRec.wi) > 0;
-
-		if ((reflection && !sampleReflection) || 
-		   (!reflection && !sampleTransmission) || measure != EDiscrete)
-			return 0.0f;
-
-		if (sampleTransmission && sampleReflection) {
-			Float Fr = fresnel(Frame::cosTheta(bRec.wi), m_extIOR, m_intIOR);
-			return reflection ? Fr : (1 - Fr);
-		} else {
-			return 1.0f;
-		}
-	}
-
 	Spectrum sample(BSDFQueryRecord &bRec, Float &pdf, const Point2 &sample) const {
 		bool sampleReflection   = (bRec.typeMask & EDeltaReflection)
 				&& (bRec.component == -1 || bRec.component == 0);

src/bsdfs/microfacet.h

@@ -50,8 +50,7 @@ public:
 	 * (ggx/phong/beckmann)
 	 */
 	MicrofacetDistribution(const std::string &name) {
-		std::string distr = 
+		std::string distr = boost::to_lower_copy(name);
-			boost::to_lower_copy(props.getString("distribution", "beckmann"));
 
 		if (distr == "beckmann")
 			m_type = EBeckmann;
@@ -171,8 +170,8 @@ public:
 	 * \brief Smith's shadow-masking function G1 for each
 	 * of the supported microfacet distributions
 	 *
-	 * \param m The microsurface normal
 	 * \param v An arbitrary direction
+	 * \param m The microsurface normal
 	 * \param alpha The surface roughness
 	 */
 	Float smithG1(const Vector &v, const Vector &m, Float alpha) const {
@@ -218,9 +217,22 @@ public:
 				return 0.0f;
 		}
 	}
+
+	/**
+	 * \brief Smith's shadow-masking function G1 for each
+	 * of the supported microfacet distributions
+	 *
+	 * \param wi The incident direction
+	 * \param wo The exitant direction
+	 * \param m The microsurface normal
+	 * \param alpha The surface roughness
+	 */
+	Float smithG(const Vector &wi, const Vector &wo, const Vector &m, Float alpha) const {
+		return smithG1(wi, m, alpha) * smithG1(wo, m, alpha);
+	}
 	
 	std::string toString() const {
-		switch (m_distribution) {
+		switch (m_type) {
 			case EBeckmann: return "beckmann"; break;
 			case EPhong: return "phong"; break;
 			case EGGX: return "ggx"; break;
@@ -230,7 +242,7 @@ public:
 		}
 	}
 private:
-	EType type;
+	EType m_type;
 };
 
 MTS_NAMESPACE_END

src/bsdfs/roughdielectric.cpp

@@ -127,15 +127,6 @@ public:
 		m_specularTransmittance = new ConstantSpectrumTexture(
 			props.getSpectrum("specularTransmittance", Spectrum(1.0f)));
 
-		Float alpha;
-		if (props.hasProperty("alphaB")) {
-			Log(EWarn, "Deprecation warning: the 'alphaB' parameter "
-				"has been renamed to 'alpha'");
-
-			alpha = props.getFloat("alphaB");
-		} else {
-			alpha = props.getFloat("alpha", 0.1f);
-		}
 
 		m_intIOR = props.getFloat("intIOR", 1.5046f);
 		m_extIOR = props.getFloat("extIOR", 1.0f);
@@ -145,10 +136,11 @@ public:
 				"refraction must be positive and differ!");
 
 		m_distribution = MicrofacetDistribution(
-			m_props.getString("distribution", "beckmann")
+			props.getString("distribution", "beckmann")
 		);
 
-		m_alpha = new ConstantFloatTexture(alpha);
+		m_alpha = new ConstantFloatTexture(
+			props.getFloat("alpha", 0.1f));
 
 		m_components.push_back(
 			EGlossyReflection | EFrontSide | EBackSide | ECanUseSampler);
@@ -184,7 +176,10 @@ public:
 		return (value < 0) ? -1.0f : 1.0f;
 	}
 
-	Spectrum eval(const BSDFQueryRecord &bRec) const {
+	Spectrum eval(const BSDFQueryRecord &bRec, EMeasure measure) const {
+		if (measure != ESolidAngle)
+			return Spectrum(0.0f);
+
 		/* Determine the type of interaction */
 		bool reflect = Frame::cosTheta(bRec.wi) 
 			* Frame::cosTheta(bRec.wo) > 0;
@@ -219,7 +214,7 @@ public:
 		}
 
 		/* Evaluate the roughness */
-		Float alpha = m_distribution.transform( 
+		Float alpha = m_distribution.transformRoughness( 
 			m_alpha->getValue(bRec.its).average());
 
 		/* Microsurface normal distribution */
@@ -231,7 +226,7 @@ public:
 		const Float F = fresnel(dot(bRec.wi, H), m_extIOR, m_intIOR);
 
 		/* Smith's shadow-masking function */
-		const Float G = smithG1(bRec.wi, H, alpha) * smithG1(bRec.wo, H, alpha);
+		const Float G = m_distribution.smithG(bRec.wi, bRec.wo, H, alpha);
 
 		if (reflect) {
 			/* Calculate the total amount of reflection */
@@ -255,7 +250,10 @@ public:
 		}
 	}
 
-	Float pdf(const BSDFQueryRecord &bRec) const {
+	Float pdf(const BSDFQueryRecord &bRec, EMeasure measure) const {
+		if (measure != ESolidAngle)
+			return 0.0f;
+
 		/* Determine the type of interaction */
 		bool sampleReflection   = ((bRec.component == -1 || bRec.component == 0)
 							  && (bRec.typeMask & EGlossyReflection)),
@@ -303,7 +301,7 @@ public:
 		}
 
 		/* Evaluate the roughness */
-		Float alpha = m_distribution.transform( 
+		Float alpha = m_distribution.transformRoughness( 
 			m_alpha->getValue(bRec.its).average());
 
 		/* Suggestion by Bruce Walter: sample using a slightly different 
@@ -386,7 +384,7 @@ public:
 		}
 
 		/* Evaluate the roughness */
-		Float alpha = m_distribution.transform( 
+		Float alpha = m_distribution.transformRoughness( 
 			m_alpha->getValue(bRec.its).average());
 
 		/* Suggestion by Bruce Walter: sample using a slightly different 
@@ -396,7 +394,7 @@ public:
 			std::abs(Frame::cosTheta(bRec.wi))));
 
 		/* Sample M, the microsurface normal */
-		const Normal m = sampleD(sample, sampleAlpha);
+		const Normal m = m_distribution.sampleD(sample, sampleAlpha);
 	
 		if (sampleExactFresnelTerm) {
 			sampleF = fresnel(dot(bRec.wi, m), m_extIOR, m_intIOR);
@@ -438,8 +436,7 @@ public:
 		}
 
 		Float numerator = m_distribution.eval(m, alpha)
-			* m_distribution.smithG1(bRec.wi, m, alpha)
+			* m_distribution.smithG(bRec.wi, bRec.wo, m, alpha)
-			* m_distribution.smithG1(bRec.wo, m, alpha)
 			* dot(bRec.wi, m);
 
 		Float denominator = m_distribution.eval(m, sampleAlpha)
@@ -508,7 +505,7 @@ public:
 		}
 
 		/* Evaluate the roughness */
-		Float alpha = m_distribution.transform( 
+		Float alpha = m_distribution.transformRoughness( 
 			m_alpha->getValue(bRec.its).average());
 
 		/* Suggestion by Bruce Walter: sample using a slightly different 
@@ -518,7 +515,7 @@ public:
 			std::abs(Frame::cosTheta(bRec.wi))));
 
 		/* Sample M, the microsurface normal */
-		const Normal m = sampleD(sample, sampleAlpha);
+		const Normal m = m_distribution.sampleD(sample, sampleAlpha);
 	
 		if (sampleExactFresnelTerm) {
 			Float sampleF = fresnel(dot(bRec.wi, m), m_extIOR, m_intIOR);

src/libcore/spectrum.cpp

@@ -96,6 +96,8 @@ Float Spectrum::m_wavelengths[SPECTRUM_SAMPLES + 1];
 void Spectrum::staticInitialization() {
 #if SPECTRUM_SAMPLES != 3
 	std::ostringstream oss;
+	oss << std::fixed;
+	oss.precision(2);
 	Float stepSize = SPECTRUM_RANGE / (Float) SPECTRUM_SAMPLES;
 	for (int i=0; i<SPECTRUM_SAMPLES + 1; i++) {
 		Float value = SPECTRUM_MIN_WAVELENGTH + stepSize * i;
@@ -406,12 +408,16 @@ void Spectrum::fromRGBE(const uint8_t rgbe[4], EConversionIntent intent) {
 std::string Spectrum::toString() const {
 	std::ostringstream oss;
 	oss << "[";
+	oss << std::fixed;
 	for (int i=0; i<SPECTRUM_SAMPLES; i++) {
 #if SPECTRUM_SAMPLES == 3
 		oss << s[i];
 #else
+		oss.precision(1);
 		oss << m_wavelengths[i] << "-" 
-			<< m_wavelengths[i+1] << "nm => " << s[i];
+			<< m_wavelengths[i+1] << "nm => ";
+		oss.precision(3);
+		oss << s[i];
 #endif
 		if (i < SPECTRUM_SAMPLES - 1)
 			oss << ", ";
@@ -607,9 +613,13 @@ Float InterpolatedSpectrum::eval(Float lambda) const {
 
 std::string InterpolatedSpectrum::toString() const {
 	std::ostringstream oss;
+	oss << std::fixed;
 	oss << "InterpolatedSpectrum[" << endl;
 	for (size_t i=0; i<m_wavelengths.size(); ++i) {
-		oss << "  " << m_wavelengths[i] << " nm  =>  " << m_values[i];
+		oss.precision(1);
+		oss << "  " << m_wavelengths[i] << " nm  =>  ";
+		oss.precision(3);
+		oss << m_values[i];
 		if (i+1 < m_wavelengths.size())
 			oss << ",";
 		oss << endl;

src/libcore/util.cpp

@@ -687,16 +687,16 @@ Float fresnelDielectric(Float cosThetaI, Float cosThetaT,
 	return (Rs * Rs + Rp * Rp) / 2.0f;
 }
 
-Spectrum fresnelConductor(Float cosTheta, const Spectrum &eta, const Spectrum &k) {
+Spectrum fresnelConductor(Float cosThetaI, const Spectrum &eta, const Spectrum &k) {
-	Spectrum tmp = (eta*eta + k*k) * (cosTheta * cosTheta);
+	Spectrum tmp = (eta*eta + k*k) * (cosThetaI * cosThetaI);
 
-	Spectrum rParl2 = (tmp - (eta * (2.0f * cosTheta)) + Spectrum(1.0f))
+	Spectrum rParl2 = (tmp - (eta * (2.0f * cosThetaI)) + Spectrum(1.0f))
-					/ (tmp + (eta * (2.0f * cosTheta)) + Spectrum(1.0f));
+					/ (tmp + (eta * (2.0f * cosThetaI)) + Spectrum(1.0f));
 
 	Spectrum tmpF = eta*eta + k*k;
 
-	Spectrum rPerp2 = (tmpF - (eta * (2.0f * cosTheta)) + Spectrum(cosTheta*cosTheta)) /
+	Spectrum rPerp2 = (tmpF - (eta * (2.0f * cosThetaI)) + Spectrum(cosThetaI*cosThetaI)) /
-					  (tmpF + (eta * (2.0f * cosTheta)) + Spectrum(cosTheta*cosTheta));
+					  (tmpF + (eta * (2.0f * cosThetaI)) + Spectrum(cosThetaI*cosThetaI));
 
 	return (rParl2 + rPerp2) / 2.0f;
 }