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0028218: Visualization, Path Tracing - Redesign path tracing materials to support two-layered model
Existing OCCT path tracing engine used very simple additive material (BSDF) model, so it was possible to reproduce behavior only of very basic materials such as metal, glass, or plastic. However, some important in CAD industry materials like car paint or ceramic could not be modeled well. In this patch, OCCT BSDF was significantly improved by replacing additive model with two-layered scattering model. Therefore, we have base diffuse, glossy, or transmissive layer, covered by one glossy/specular coat. The layers themselves have no thickness; they can simply reflect light or transmits it to the layer under it. Balancing different combinations of layer properties can produce a wide range of different effects. At the same time, disabling the first (coat) layer allows to keep full compatibility with previously supported scattering model. All new parameters are available via 'vbsdf' command. Location of new sample for few material examples: samples\tcl\pathtrace_materials.tcl Fix shader compilation issue. Fix test case sample_ball_alpha. Shaders_PathtraceBase_fs.pxx - regenerate resource from origin
This commit is contained in:
dbp
bugmaster
@@ -29,25 +29,25 @@ struct SLocalSpace
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};
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//! Describes material properties (BSDF).
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struct SMaterial
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struct SBSDF
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{
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//! Weight of the Lambertian BRDF.
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//! Weight of coat specular/glossy BRDF.
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vec4 Kc;
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//! Weight of base diffuse BRDF.
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vec4 Kd;
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//! Weight of the reflection BRDF.
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vec3 Kr;
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//! Weight of the transmission BTDF.
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vec3 Kt;
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//! Weight of the Blinn BRDF (and roughness).
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//! Weight of base specular/glossy BRDF.
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vec4 Ks;
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//! Fresnel coefficients.
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vec3 Fresnel;
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//! Weight of base specular/glossy BTDF.
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vec3 Kt;
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//! Absorption color and intensity of the media.
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vec4 Absorption;
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//! Fresnel coefficients of coat layer.
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vec3 FresnelCoat;
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//! Fresnel coefficients of base layer.
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vec3 FresnelBase;
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};
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///////////////////////////////////////////////////////////////////////////////////////
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@@ -148,19 +148,19 @@ float fresnelDielectric (in float theCosI,
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//=======================================================================
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float fresnelDielectric (in float theCosI, in float theIndex)
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{
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float aFresnel = 1.f;
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float anEtaI = theCosI > 0.f ? 1.f : theIndex;
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float anEtaT = theCosI > 0.f ? theIndex : 1.f;
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float aSinT = (anEtaI / anEtaT) * sqrt (1.f - theCosI * theCosI);
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float aSinT2 = (anEtaI * anEtaI) / (anEtaT * anEtaT) * (1.f - theCosI * theCosI);
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if (aSinT >= 1.f)
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if (aSinT2 < 1.f)
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{
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return 1.f;
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aFresnel = fresnelDielectric (abs (theCosI), sqrt (1.f - aSinT2), anEtaI, anEtaT);
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}
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float aCosT = sqrt (1.f - aSinT * aSinT);
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return fresnelDielectric (abs (theCosI), aCosT, anEtaI, anEtaT);
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return aFresnel;
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}
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//=======================================================================
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@@ -197,22 +197,26 @@ float fresnelConductor (in float theCosI, in float theEta, in float theK)
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//=======================================================================
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vec3 fresnelMedia (in float theCosI, in vec3 theFresnel)
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{
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vec3 aFresnel;
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if (theFresnel.x > FRESNEL_SCHLICK)
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{
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return fresnelSchlick (abs (theCosI), theFresnel);
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aFresnel = fresnelSchlick (abs (theCosI), theFresnel);
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}
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if (theFresnel.x > FRESNEL_CONSTANT)
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else if (theFresnel.x > FRESNEL_CONSTANT)
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{
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return vec3 (theFresnel.z);
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aFresnel = vec3 (theFresnel.z);
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}
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if (theFresnel.x > FRESNEL_CONDUCTOR)
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else if (theFresnel.x > FRESNEL_CONDUCTOR)
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{
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return vec3 (fresnelConductor (abs (theCosI), theFresnel.y, theFresnel.z));
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aFresnel = vec3 (fresnelConductor (abs (theCosI), theFresnel.y, theFresnel.z));
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}
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else
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{
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aFresnel = vec3 (fresnelDielectric (theCosI, theFresnel.y));
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}
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return vec3 (fresnelDielectric (theCosI, theFresnel.y));
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return aFresnel;
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}
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//=======================================================================
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@@ -249,36 +253,34 @@ float EvalLambertianReflection (in vec3 theWi, in vec3 theWo)
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return (theWi.z <= 0.f || theWo.z <= 0.f) ? 0.f : theWi.z * (1.f / M_PI);
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}
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#define FLT_EPSILON 1.0e-5f
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//=======================================================================
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// function : SmithG1
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// purpose :
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//=======================================================================
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float SmithG1 (in vec3 theDirection, in vec3 theM, in float theRoughness)
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{
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if (dot (theDirection, theM) * theDirection.z <= 0.f)
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float aResult = 0.f;
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if (dot (theDirection, theM) * theDirection.z > 0.f)
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{
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return 0.f;
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float aTanThetaM = sqrt (1.f - theDirection.z * theDirection.z) / theDirection.z;
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if (aTanThetaM == 0.f)
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{
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aResult = 1.f;
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}
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else
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{
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float aVal = 1.f / (theRoughness * aTanThetaM);
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// Use rational approximation to shadowing-masking function (from Mitsuba)
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aResult = (3.535f + 2.181f * aVal) / (1.f / aVal + 2.276f + 2.577f * aVal);
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}
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}
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float aTanThetaM = sqrt (1.f - theDirection.z * theDirection.z) / theDirection.z;
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if (aTanThetaM == 0.0f)
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{
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return 1.f;
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}
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float aVal = 1.f / (theRoughness * aTanThetaM);
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if (aVal >= 1.6f)
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{
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return 1.f;
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}
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// Use fast and accurate rational approximation to the
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// shadowing-masking function (from Mitsuba renderer)
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float aSqr = aVal * aVal;
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return (3.535f * aVal + 2.181f * aSqr) / (1.f + 2.276f * aVal + 2.577f * aSqr);
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return min (aResult, 1.f);
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}
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//=======================================================================
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@@ -306,18 +308,31 @@ vec3 EvalBlinnReflection (in vec3 theWi, in vec3 theWo, in vec3 theFresnel, in f
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}
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//=======================================================================
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// function : EvalMaterial
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// function : EvalBsdfLayered
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// purpose : Evaluates BSDF for specified material, with cos(N, PSI)
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//=======================================================================
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vec3 EvalMaterial (in SMaterial theBSDF, in vec3 theWi, in vec3 theWo)
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vec3 EvalBsdfLayered (in SBSDF theBSDF, in vec3 theWi, in vec3 theWo)
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{
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#ifdef TWO_SIDED_BXDF
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theWi.z *= sign (theWi.z);
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theWo.z *= sign (theWo.z);
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#endif
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return theBSDF.Kd.rgb * EvalLambertianReflection (theWi, theWo) +
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theBSDF.Ks.rgb * EvalBlinnReflection (theWi, theWo, theBSDF.Fresnel, theBSDF.Ks.w);
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vec3 aBxDF = theBSDF.Kd.rgb * EvalLambertianReflection (theWi, theWo);
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if (theBSDF.Ks.w > FLT_EPSILON)
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{
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aBxDF += theBSDF.Ks.rgb * EvalBlinnReflection (theWi, theWo, theBSDF.FresnelBase, theBSDF.Ks.w);
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}
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aBxDF *= UNIT - fresnelMedia (theWo.z, theBSDF.FresnelCoat);
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if (theBSDF.Kc.w > FLT_EPSILON)
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{
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aBxDF += theBSDF.Kc.rgb * EvalBlinnReflection (theWi, theWo, theBSDF.FresnelCoat, theBSDF.Kc.w);
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}
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return aBxDF;
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}
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//=======================================================================
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@@ -349,7 +364,7 @@ vec3 SampleLambertianReflection (in vec3 theWo, out vec3 theWi, inout float theP
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}
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//=======================================================================
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// function : SampleBlinnReflection
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// function : SampleGlossyBlinnReflection
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// purpose : Samples Blinn BRDF, W = BRDF * cos(N, PSI) / PDF(PSI)
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// The BRDF is a product of three main terms, D, G, and F,
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// which is then divided by two cosine terms. Here we perform
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@@ -358,7 +373,7 @@ vec3 SampleLambertianReflection (in vec3 theWo, out vec3 theWi, inout float theP
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// terms would be complex, and it is the D term that accounts
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// for most of the variation.
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//=======================================================================
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vec3 SampleBlinnReflection (in vec3 theWo, out vec3 theWi, in vec3 theFresnel, in float theRoughness, inout float thePDF)
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vec3 SampleGlossyBlinnReflection (in vec3 theWo, out vec3 theWi, in vec3 theFresnel, in float theRoughness, inout float thePDF)
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{
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float aKsi1 = RandFloat();
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float aKsi2 = RandFloat();
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@@ -396,7 +411,7 @@ vec3 SampleBlinnReflection (in vec3 theWo, out vec3 theWi, in vec3 theFresnel, i
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}
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// Jacobian of half-direction mapping
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thePDF /= 4.f * dot (theWi, aM);
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thePDF /= 4.f * aCosDelta;
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// compute shadow-masking coefficient
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float aG = SmithG1 (theWo, aM, theRoughness) *
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@@ -411,139 +426,152 @@ vec3 SampleBlinnReflection (in vec3 theWo, out vec3 theWi, in vec3 theFresnel, i
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}
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//=======================================================================
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// function : SampleSpecularReflection
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// purpose : Samples specular BRDF, W = BRDF * cos(N, PSI) / PDF(PSI)
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//=======================================================================
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vec3 SampleSpecularReflection (in vec3 theWo, out vec3 theWi, in vec3 theFresnel)
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{
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// Sample input direction
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theWi = vec3 (-theWo.x,
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-theWo.y,
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theWo.z);
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#ifdef TWO_SIDED_BXDF
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return fresnelMedia (theWo.z, theFresnel);
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#else
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return fresnelMedia (theWo.z, theFresnel) * step (0.f, theWo.z);
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#endif
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}
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//=======================================================================
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// function : SampleSpecularTransmission
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// purpose : Samples specular BTDF, W = BRDF * cos(N, PSI) / PDF(PSI)
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//=======================================================================
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vec3 SampleSpecularTransmission (in vec3 theWo, out vec3 theWi, in vec3 theWeight, in vec3 theFresnel, inout bool theInside)
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{
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vec3 aFactor = fresnelMedia (theWo.z, theFresnel);
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float aReflection = convolve (aFactor, theWeight);
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// sample specular BRDF/BTDF
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if (RandFloat() <= aReflection)
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{
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theWi = vec3 (-theWo.x,
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-theWo.y,
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theWo.z);
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theWeight = aFactor * (1.f / aReflection);
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}
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else
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{
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theInside = !theInside;
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transmitted (theFresnel.y, theWo, theWi);
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theWeight = (UNIT - aFactor) * (1.f / (1.f - aReflection));
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}
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return theWeight;
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}
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#define FLT_EPSILON 1.0e-5F
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//=======================================================================
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// function : BsdfPdf
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// function : BsdfPdfLayered
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// purpose : Calculates BSDF of sampling input knowing output
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//=======================================================================
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float BsdfPdf (in SMaterial theBSDF, in vec3 theWo, in vec3 theWi, in vec3 theWeight)
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float BsdfPdfLayered (in SBSDF theBSDF, in vec3 theWo, in vec3 theWi, in vec3 theWeight)
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{
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float aPd = convolve (theBSDF.Kd.rgb, theWeight);
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float aPs = convolve (theBSDF.Ks.rgb, theWeight);
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float aPr = convolve (theBSDF.Kr.rgb, theWeight);
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float aPt = convolve (theBSDF.Kt.rgb, theWeight);
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float aReflection = aPd + aPs + aPr + aPt;
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float aPDF = 0.f; // PDF of sampling input direction
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// We choose whether the light is reflected or transmitted
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// by the coating layer according to the Fresnel equations
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vec3 aCoatF = fresnelMedia (theWo.z, theBSDF.FresnelCoat);
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// Coat BRDF is scaled by its Fresnel reflectance term. For
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// reasons of simplicity we scale base BxDFs only by coat's
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// Fresnel transmittance term
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vec3 aCoatT = UNIT - aCoatF;
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float aPc = dot (theBSDF.Kc.rgb * aCoatF, theWeight);
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float aPd = dot (theBSDF.Kd.rgb * aCoatT, theWeight);
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float aPs = dot (theBSDF.Ks.rgb * aCoatT, theWeight);
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float aPt = dot (theBSDF.Kt.rgb * aCoatT, theWeight);
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if (theWi.z * theWo.z > 0.f)
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{
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vec3 aH = normalize (theWi + theWo);
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// roughness value --> Blinn exponent
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float aPower = max (2.f / (theBSDF.Ks.w * theBSDF.Ks.w) - 2.f, 0.f);
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aPDF = aPd * abs (theWi.z / M_PI);
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aPDF = aPd * abs (theWi.z / M_PI) +
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aPs * (aPower + 2.f) * (1.f / M_2_PI) * pow (abs (aH.z), aPower + 1.f) / (4.f * dot (theWi, aH));
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if (theBSDF.Kc.w > FLT_EPSILON)
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{
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float aPower = max (2.f / (theBSDF.Kc.w * theBSDF.Kc.w) - 2.f, 0.f); // roughness --> exponent
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aPDF += aPc * (aPower + 2.f) * (0.25f / M_2_PI) * pow (abs (aH.z), aPower + 1.f) / dot (theWi, aH);
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}
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if (theBSDF.Ks.w > FLT_EPSILON)
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{
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float aPower = max (2.f / (theBSDF.Ks.w * theBSDF.Ks.w) - 2.f, 0.f); // roughness --> exponent
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aPDF += aPs * (aPower + 2.f) * (0.25f / M_2_PI) * pow (abs (aH.z), aPower + 1.f) / dot (theWi, aH);
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}
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}
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return aPDF / aReflection;
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return aPDF / (aPc + aPd + aPs + aPt);
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}
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//! Tool macro to handle sampling of particular BxDF
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#define PICK_BXDF(p, k) aPDF = p / aReflection; theWeight *= k / aPDF;
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#define PICK_BXDF_LAYER(p, k) aPDF = p / aTotalR; theWeight *= k / aPDF;
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//=======================================================================
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// function : SampleBsdf
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// function : SampleBsdfLayered
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// purpose : Samples specified composite material (BSDF)
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//=======================================================================
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float SampleBsdf (in SMaterial theBSDF, in vec3 theWo, out vec3 theWi, inout vec3 theWeight, inout bool theInside)
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float SampleBsdfLayered (in SBSDF theBSDF, in vec3 theWo, out vec3 theWi, inout vec3 theWeight, inout bool theInside)
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{
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// compute probability of each reflection type (BxDF)
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float aPd = convolve (theBSDF.Kd.rgb, theWeight);
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float aPs = convolve (theBSDF.Ks.rgb, theWeight);
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float aPr = convolve (theBSDF.Kr.rgb, theWeight);
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float aPt = convolve (theBSDF.Kt.rgb, theWeight);
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// NOTE: OCCT uses two-layer material model. We have base diffuse, glossy, or transmissive
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// layer, covered by one glossy/specular coat. In the current model, the layers themselves
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// have no thickness; they can simply reflect light or transmits it to the layer under it.
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// We use actual BRDF model only for direct reflection by the coat layer. For transmission
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// through this layer, we approximate it as a flat specular surface.
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float aReflection = aPd + aPs + aPr + aPt;
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float aPDF = 0.f; // PDF of sampled direction
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// choose BxDF component to sample
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float aKsi = aReflection * RandFloat();
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// We choose whether the light is reflected or transmitted
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// by the coating layer according to the Fresnel equations
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vec3 aCoatF = fresnelMedia (theWo.z, theBSDF.FresnelCoat);
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// BxDF's PDF of sampled direction
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float aPDF = 0.f;
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// Coat BRDF is scaled by its Fresnel term. According to
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// Wilkie-Weidlich layered BSDF model, transmission term
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// for light passing through the coat at direction I and
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// leaving it in O is T = ( 1 - F (O) ) x ( 1 - F (I) ).
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// For reasons of simplicity, we discard the second term
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// and scale base BxDFs only by the first term.
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vec3 aCoatT = UNIT - aCoatF;
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if (aKsi < aPd) // diffuse reflection
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float aPc = dot (theBSDF.Kc.rgb * aCoatF, theWeight);
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float aPd = dot (theBSDF.Kd.rgb * aCoatT, theWeight);
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float aPs = dot (theBSDF.Ks.rgb * aCoatT, theWeight);
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float aPt = dot (theBSDF.Kt.rgb * aCoatT, theWeight);
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// Calculate total reflection probability
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float aTotalR = (aPc + aPd) + (aPs + aPt);
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// Generate random variable to select BxDF
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float aKsi = aTotalR * RandFloat();
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if (aKsi < aPc) // REFLECTION FROM COAT
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{
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PICK_BXDF (aPd, theBSDF.Kd.rgb);
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PICK_BXDF_LAYER (aPc, theBSDF.Kc.rgb)
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theWeight *= SampleLambertianReflection (theWo, theWi, aPDF);
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if (theBSDF.Kc.w < FLT_EPSILON)
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{
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theWeight *= aCoatF;
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theWi = vec3 (-theWo.x,
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-theWo.y,
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theWo.z);
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}
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else
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{
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theWeight *= SampleGlossyBlinnReflection (theWo, theWi, theBSDF.FresnelCoat, theBSDF.Kc.w, aPDF);
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}
|
||||
|
||||
aPDF = mix (aPDF, MAXFLOAT, theBSDF.Kc.w < FLT_EPSILON);
|
||||
}
|
||||
else if (aKsi < aPd + aPs) // glossy reflection
|
||||
else if (aKsi < aTotalR) // REFLECTION FROM BASE
|
||||
{
|
||||
PICK_BXDF (aPs, theBSDF.Ks.rgb);
|
||||
theWeight *= aCoatT;
|
||||
|
||||
theWeight *= SampleBlinnReflection (theWo, theWi, theBSDF.Fresnel, theBSDF.Ks.w, aPDF);
|
||||
}
|
||||
else if (aKsi < aPd + aPs + aPr) // specular reflection
|
||||
{
|
||||
PICK_BXDF (aPr, theBSDF.Kr.rgb);
|
||||
if (aKsi < aPc + aPd) // diffuse BRDF
|
||||
{
|
||||
PICK_BXDF_LAYER (aPd, theBSDF.Kd.rgb)
|
||||
|
||||
aPDF = MAXFLOAT;
|
||||
theWeight *= SampleLambertianReflection (theWo, theWi, aPDF);
|
||||
}
|
||||
else if (aKsi < (aPc + aPd) + aPs) // specular/glossy BRDF
|
||||
{
|
||||
PICK_BXDF_LAYER (aPs, theBSDF.Ks.rgb)
|
||||
|
||||
theWeight *= SampleSpecularReflection (theWo, theWi, theBSDF.Fresnel);
|
||||
}
|
||||
else if (aKsi < aReflection) // specular transmission
|
||||
{
|
||||
PICK_BXDF (aPt, theBSDF.Kt.rgb);
|
||||
if (theBSDF.Ks.w < FLT_EPSILON)
|
||||
{
|
||||
theWeight *= fresnelMedia (theWo.z, theBSDF.FresnelBase);
|
||||
|
||||
aPDF = MAXFLOAT;
|
||||
theWi = vec3 (-theWo.x,
|
||||
-theWo.y,
|
||||
theWo.z);
|
||||
}
|
||||
else
|
||||
{
|
||||
theWeight *= SampleGlossyBlinnReflection (theWo, theWi, theBSDF.FresnelBase, theBSDF.Ks.w, aPDF);
|
||||
}
|
||||
|
||||
theWeight *= SampleSpecularTransmission (theWo, theWi, theWeight, theBSDF.Fresnel, theInside);
|
||||
aPDF = mix (aPDF, MAXFLOAT, theBSDF.Ks.w < FLT_EPSILON);
|
||||
}
|
||||
else // specular transmission
|
||||
{
|
||||
PICK_BXDF_LAYER (aPt, theBSDF.Kt.rgb)
|
||||
|
||||
// refracted direction should exist if we are here
|
||||
transmitted (theBSDF.FresnelCoat.y, theWo, theWi);
|
||||
|
||||
theInside = !theInside; aPDF = MAXFLOAT;
|
||||
}
|
||||
}
|
||||
|
||||
// path termination for extra small weights
|
||||
theWeight = mix (ZERO, theWeight, step (FLT_EPSILON, aReflection));
|
||||
theWeight = mix (ZERO, theWeight, step (FLT_EPSILON, aTotalR));
|
||||
|
||||
return aPDF;
|
||||
}
|
||||
@@ -689,15 +717,16 @@ vec3 IntersectLight (in SRay theRay, in int theDepth, in float theHitDistance, o
|
||||
#define MIN_THROUGHPUT vec3 (1.0e-3f)
|
||||
#define MIN_CONTRIBUTION vec3 (1.0e-2f)
|
||||
|
||||
#define MATERIAL_KD(index) (18 * index + 11)
|
||||
#define MATERIAL_KR(index) (18 * index + 12)
|
||||
#define MATERIAL_KT(index) (18 * index + 13)
|
||||
#define MATERIAL_KS(index) (18 * index + 14)
|
||||
#define MATERIAL_LE(index) (18 * index + 15)
|
||||
#define MATERIAL_FRESNEL(index) (18 * index + 16)
|
||||
#define MATERIAL_ABSORPT(index) (18 * index + 17)
|
||||
#define MATERIAL_KC(index) (19 * index + 11)
|
||||
#define MATERIAL_KD(index) (19 * index + 12)
|
||||
#define MATERIAL_KS(index) (19 * index + 13)
|
||||
#define MATERIAL_KT(index) (19 * index + 14)
|
||||
#define MATERIAL_LE(index) (19 * index + 15)
|
||||
#define MATERIAL_FRESNEL_COAT(index) (19 * index + 16)
|
||||
#define MATERIAL_FRESNEL_BASE(index) (19 * index + 17)
|
||||
#define MATERIAL_ABSORPT_BASE(index) (19 * index + 18)
|
||||
|
||||
//! Enables experimental russian roulette sampling path termination.
|
||||
//! Enables experimental Russian roulette sampling path termination.
|
||||
//! In most cases, it provides faster image convergence with minimal
|
||||
//! bias, so it is enabled by default.
|
||||
#define RUSSIAN_ROULETTE
|
||||
@@ -712,6 +741,18 @@ vec3 IntersectLight (in SRay theRay, in int theDepth, in float theHitDistance, o
|
||||
#define FRAME_STEP 5
|
||||
#endif
|
||||
|
||||
//=======================================================================
|
||||
// function : IsNotZero
|
||||
// purpose : Checks whether BSDF reflects direct light
|
||||
//=======================================================================
|
||||
bool IsNotZero (in SBSDF theBSDF, in vec3 theThroughput)
|
||||
{
|
||||
vec3 aGlossy = theBSDF.Kc.rgb * step (FLT_EPSILON, theBSDF.Kc.w) +
|
||||
theBSDF.Ks.rgb * step (FLT_EPSILON, theBSDF.Ks.w);
|
||||
|
||||
return convolve (theBSDF.Kd.rgb + aGlossy, theThroughput) > FLT_EPSILON;
|
||||
}
|
||||
|
||||
//=======================================================================
|
||||
// function : PathTrace
|
||||
// purpose : Calculates radiance along the given ray
|
||||
@@ -766,17 +807,25 @@ vec4 PathTrace (in SRay theRay, in vec3 theInverse, in int theNbSamples)
|
||||
aRaytraceDepth = (aNDCPoint.z / aNDCPoint.w + aPolygonOffset * POLYGON_OFFSET_SCALE) * 0.5f + 0.5f;
|
||||
}
|
||||
|
||||
// fetch material (BSDF)
|
||||
SMaterial aMaterial = SMaterial (
|
||||
vec4 (texelFetch (uRaytraceMaterialTexture, MATERIAL_KD (aTriIndex.w))),
|
||||
vec3 (texelFetch (uRaytraceMaterialTexture, MATERIAL_KR (aTriIndex.w))),
|
||||
vec3 (texelFetch (uRaytraceMaterialTexture, MATERIAL_KT (aTriIndex.w))),
|
||||
vec4 (texelFetch (uRaytraceMaterialTexture, MATERIAL_KS (aTriIndex.w))),
|
||||
vec3 (texelFetch (uRaytraceMaterialTexture, MATERIAL_FRESNEL (aTriIndex.w))),
|
||||
vec4 (texelFetch (uRaytraceMaterialTexture, MATERIAL_ABSORPT (aTriIndex.w))));
|
||||
SBSDF aBSDF;
|
||||
|
||||
// fetch BxDF weights
|
||||
aBSDF.Kc = texelFetch (uRaytraceMaterialTexture, MATERIAL_KC (aTriIndex.w));
|
||||
aBSDF.Kd = texelFetch (uRaytraceMaterialTexture, MATERIAL_KD (aTriIndex.w));
|
||||
aBSDF.Ks = texelFetch (uRaytraceMaterialTexture, MATERIAL_KS (aTriIndex.w));
|
||||
aBSDF.Kt = texelFetch (uRaytraceMaterialTexture, MATERIAL_KT (aTriIndex.w)).rgb;
|
||||
|
||||
// compute smooth normal (in parallel with fetch)
|
||||
vec3 aNormal = SmoothNormal (aHit.UV, aTriIndex);
|
||||
|
||||
aNormal = normalize (vec3 (dot (aInvTransf0, aNormal),
|
||||
dot (aInvTransf1, aNormal),
|
||||
dot (aInvTransf2, aNormal)));
|
||||
|
||||
SLocalSpace aSpace = buildLocalSpace (aNormal);
|
||||
|
||||
#ifdef USE_TEXTURES
|
||||
if (aMaterial.Kd.w >= 0.f)
|
||||
if (aBSDF.Kd.w >= 0.f)
|
||||
{
|
||||
vec4 aTexCoord = vec4 (SmoothUV (aHit.UV, aTriIndex), 0.f, 1.f);
|
||||
|
||||
@@ -789,32 +838,23 @@ vec4 PathTrace (in SRay theRay, in vec3 theInverse, in int theNbSamples)
|
||||
dot (aTrsfRow2, aTexCoord));
|
||||
|
||||
vec4 aTexColor = textureLod (
|
||||
sampler2D (uTextureSamplers[int (aMaterial.Kd.w)]), aTexCoord.st, 0.f);
|
||||
sampler2D (uTextureSamplers[int (aBSDF.Kd.w)]), aTexCoord.st, 0.f);
|
||||
|
||||
aMaterial.Kd.rgb *= (aTexColor.rgb * aTexColor.rgb) * aTexColor.w; // de-gamma correction (for gamma = 2)
|
||||
aBSDF.Kd.rgb *= (aTexColor.rgb * aTexColor.rgb) * aTexColor.w; // de-gamma correction (for gamma = 2)
|
||||
|
||||
if (aTexColor.w != 1.0f)
|
||||
{
|
||||
// mix transparency BTDF with texture alpha-channel
|
||||
aMaterial.Kt = (UNIT - aTexColor.www) + aTexColor.w * aMaterial.Kt;
|
||||
aBSDF.Kt = (UNIT - aTexColor.www) + aTexColor.w * aBSDF.Kt;
|
||||
}
|
||||
}
|
||||
#endif
|
||||
|
||||
// compute smooth normal
|
||||
vec3 aNormal = SmoothNormal (aHit.UV, aTriIndex);
|
||||
// fetch Fresnel reflectance for both layers
|
||||
aBSDF.FresnelCoat = texelFetch (uRaytraceMaterialTexture, MATERIAL_FRESNEL_COAT (aTriIndex.w)).xyz;
|
||||
aBSDF.FresnelBase = texelFetch (uRaytraceMaterialTexture, MATERIAL_FRESNEL_BASE (aTriIndex.w)).xyz;
|
||||
|
||||
aNormal = normalize (vec3 (dot (aInvTransf0, aNormal),
|
||||
dot (aInvTransf1, aNormal),
|
||||
dot (aInvTransf2, aNormal)));
|
||||
|
||||
SLocalSpace aSpace = buildLocalSpace (aNormal);
|
||||
|
||||
// account for self-emission (not stored in the material)
|
||||
aRadiance += aThroughput * texelFetch (
|
||||
uRaytraceMaterialTexture, MATERIAL_LE (aTriIndex.w)).rgb;
|
||||
|
||||
if (uLightCount > 0 && convolve (aMaterial.Kd.rgb + aMaterial.Ks.rgb, aThroughput) > 0.f)
|
||||
if (uLightCount > 0 && IsNotZero (aBSDF, aThroughput))
|
||||
{
|
||||
aExpPDF = 1.f / uLightCount;
|
||||
|
||||
@@ -833,14 +873,14 @@ vec4 PathTrace (in SRay theRay, in vec3 theInverse, in int theNbSamples)
|
||||
aLight.xyz = SampleLight (aLight.xyz, aDistance,
|
||||
aLight.w == 0.f /* is infinite */, aParam.w /* max cos or radius */, aExpPDF);
|
||||
|
||||
aImpPDF = BsdfPdf (aMaterial,
|
||||
aImpPDF = BsdfPdfLayered (aBSDF,
|
||||
toLocalSpace (-theRay.Direct, aSpace), toLocalSpace (aLight.xyz, aSpace), aThroughput);
|
||||
|
||||
// MIS weight including division by explicit PDF
|
||||
float aMIS = (aExpPDF == MAXFLOAT) ? 1.f : aExpPDF / (aExpPDF * aExpPDF + aImpPDF * aImpPDF);
|
||||
|
||||
vec3 aContrib = aMIS * aParam.rgb /* Le */ * EvalMaterial (
|
||||
aMaterial, toLocalSpace (aLight.xyz, aSpace), toLocalSpace (-theRay.Direct, aSpace));
|
||||
vec3 aContrib = aMIS * aParam.rgb /* Le */ * EvalBsdfLayered (
|
||||
aBSDF, toLocalSpace (aLight.xyz, aSpace), toLocalSpace (-theRay.Direct, aSpace));
|
||||
|
||||
if (any (greaterThan (aContrib, MIN_CONTRIBUTION))) // check if light source is important
|
||||
{
|
||||
@@ -852,25 +892,29 @@ vec4 PathTrace (in SRay theRay, in vec3 theInverse, in int theNbSamples)
|
||||
float aVisibility = SceneAnyHit (aShadow,
|
||||
InverseDirection (aLight.xyz), aLight.w == 0.f ? MAXFLOAT : aDistance);
|
||||
|
||||
aRadiance += aVisibility * aThroughput * aContrib;
|
||||
aRadiance += aVisibility * (aThroughput * aContrib);
|
||||
}
|
||||
}
|
||||
|
||||
// account for self-emission
|
||||
aRadiance += aThroughput * texelFetch (uRaytraceMaterialTexture, MATERIAL_LE (aTriIndex.w)).rgb;
|
||||
|
||||
if (aInMedium) // handle attenuation
|
||||
{
|
||||
aThroughput *= exp (-aHit.Time *
|
||||
aMaterial.Absorption.w * (UNIT - aMaterial.Absorption.rgb));
|
||||
vec4 aScattering = texelFetch (uRaytraceMaterialTexture, MATERIAL_ABSORPT_BASE (aTriIndex.w));
|
||||
|
||||
aThroughput *= exp (-aHit.Time * aScattering.w * (UNIT - aScattering.rgb));
|
||||
}
|
||||
|
||||
vec3 anInput = UNIT; // sampled input direction
|
||||
|
||||
aImpPDF = SampleBsdf (aMaterial,
|
||||
aImpPDF = SampleBsdfLayered (aBSDF,
|
||||
toLocalSpace (-theRay.Direct, aSpace), anInput, aThroughput, aInMedium);
|
||||
|
||||
float aSurvive = 1.f;
|
||||
float aSurvive = float (any (greaterThan (aThroughput, MIN_THROUGHPUT)));
|
||||
|
||||
#ifdef RUSSIAN_ROULETTE
|
||||
aSurvive = aDepth < 3 ? 1.f : min (dot (LUMA, aThroughput), 0.95f);
|
||||
aSurvive = aDepth < 3 ? aSurvive : min (dot (LUMA, aThroughput), 0.95f);
|
||||
#endif
|
||||
|
||||
// here, we additionally increase path length for non-diffuse bounces
|
||||
|
||||
@@ -353,16 +353,16 @@ struct SSubTree
|
||||
ivec4 SubData;
|
||||
};
|
||||
|
||||
#define MATERIAL_AMBN(index) (18 * index + 0)
|
||||
#define MATERIAL_DIFF(index) (18 * index + 1)
|
||||
#define MATERIAL_SPEC(index) (18 * index + 2)
|
||||
#define MATERIAL_EMIS(index) (18 * index + 3)
|
||||
#define MATERIAL_REFL(index) (18 * index + 4)
|
||||
#define MATERIAL_REFR(index) (18 * index + 5)
|
||||
#define MATERIAL_TRAN(index) (18 * index + 6)
|
||||
#define MATERIAL_TRS1(index) (18 * index + 7)
|
||||
#define MATERIAL_TRS2(index) (18 * index + 8)
|
||||
#define MATERIAL_TRS3(index) (18 * index + 9)
|
||||
#define MATERIAL_AMBN(index) (19 * index + 0)
|
||||
#define MATERIAL_DIFF(index) (19 * index + 1)
|
||||
#define MATERIAL_SPEC(index) (19 * index + 2)
|
||||
#define MATERIAL_EMIS(index) (19 * index + 3)
|
||||
#define MATERIAL_REFL(index) (19 * index + 4)
|
||||
#define MATERIAL_REFR(index) (19 * index + 5)
|
||||
#define MATERIAL_TRAN(index) (19 * index + 6)
|
||||
#define MATERIAL_TRS1(index) (19 * index + 7)
|
||||
#define MATERIAL_TRS2(index) (19 * index + 8)
|
||||
#define MATERIAL_TRS3(index) (19 * index + 9)
|
||||
|
||||
#define TRS_OFFSET(treelet) treelet.SubData.x
|
||||
#define BVH_OFFSET(treelet) treelet.SubData.y
|
||||
|
||||
@@ -32,25 +32,25 @@ static const char Shaders_PathtraceBase_fs[] =
|
||||
"};\n"
|
||||
"\n"
|
||||
"//! Describes material properties (BSDF).\n"
|
||||
"struct SMaterial\n"
|
||||
"struct SBSDF\n"
|
||||
"{\n"
|
||||
" //! Weight of the Lambertian BRDF.\n"
|
||||
" //! Weight of coat specular/glossy BRDF.\n"
|
||||
" vec4 Kc;\n"
|
||||
"\n"
|
||||
" //! Weight of base diffuse BRDF.\n"
|
||||
" vec4 Kd;\n"
|
||||
"\n"
|
||||
" //! Weight of the reflection BRDF.\n"
|
||||
" vec3 Kr;\n"
|
||||
"\n"
|
||||
" //! Weight of the transmission BTDF.\n"
|
||||
" vec3 Kt;\n"
|
||||
"\n"
|
||||
" //! Weight of the Blinn BRDF (and roughness).\n"
|
||||
" //! Weight of base specular/glossy BRDF.\n"
|
||||
" vec4 Ks;\n"
|
||||
"\n"
|
||||
" //! Fresnel coefficients.\n"
|
||||
" vec3 Fresnel;\n"
|
||||
" //! Weight of base specular/glossy BTDF.\n"
|
||||
" vec3 Kt;\n"
|
||||
"\n"
|
||||
" //! Absorption color and intensity of the media.\n"
|
||||
" vec4 Absorption;\n"
|
||||
" //! Fresnel coefficients of coat layer.\n"
|
||||
" vec3 FresnelCoat;\n"
|
||||
"\n"
|
||||
" //! Fresnel coefficients of base layer.\n"
|
||||
" vec3 FresnelBase;\n"
|
||||
"};\n"
|
||||
"\n"
|
||||
"///////////////////////////////////////////////////////////////////////////////////////\n"
|
||||
@@ -151,19 +151,19 @@ static const char Shaders_PathtraceBase_fs[] =
|
||||
"//=======================================================================\n"
|
||||
"float fresnelDielectric (in float theCosI, in float theIndex)\n"
|
||||
"{\n"
|
||||
" float aFresnel = 1.f;\n"
|
||||
"\n"
|
||||
" float anEtaI = theCosI > 0.f ? 1.f : theIndex;\n"
|
||||
" float anEtaT = theCosI > 0.f ? theIndex : 1.f;\n"
|
||||
"\n"
|
||||
" float aSinT = (anEtaI / anEtaT) * sqrt (1.f - theCosI * theCosI);\n"
|
||||
" float aSinT2 = (anEtaI * anEtaI) / (anEtaT * anEtaT) * (1.f - theCosI * theCosI);\n"
|
||||
"\n"
|
||||
" if (aSinT >= 1.f)\n"
|
||||
" if (aSinT2 < 1.f)\n"
|
||||
" {\n"
|
||||
" return 1.f;\n"
|
||||
" aFresnel = fresnelDielectric (abs (theCosI), sqrt (1.f - aSinT2), anEtaI, anEtaT);\n"
|
||||
" }\n"
|
||||
"\n"
|
||||
" float aCosT = sqrt (1.f - aSinT * aSinT);\n"
|
||||
"\n"
|
||||
" return fresnelDielectric (abs (theCosI), aCosT, anEtaI, anEtaT);\n"
|
||||
" return aFresnel;\n"
|
||||
"}\n"
|
||||
"\n"
|
||||
"//=======================================================================\n"
|
||||
@@ -200,22 +200,26 @@ static const char Shaders_PathtraceBase_fs[] =
|
||||
"//=======================================================================\n"
|
||||
"vec3 fresnelMedia (in float theCosI, in vec3 theFresnel)\n"
|
||||
"{\n"
|
||||
" vec3 aFresnel;\n"
|
||||
"\n"
|
||||
" if (theFresnel.x > FRESNEL_SCHLICK)\n"
|
||||
" {\n"
|
||||
" return fresnelSchlick (abs (theCosI), theFresnel);\n"
|
||||
" aFresnel = fresnelSchlick (abs (theCosI), theFresnel);\n"
|
||||
" }\n"
|
||||
"\n"
|
||||
" if (theFresnel.x > FRESNEL_CONSTANT)\n"
|
||||
" else if (theFresnel.x > FRESNEL_CONSTANT)\n"
|
||||
" {\n"
|
||||
" return vec3 (theFresnel.z);\n"
|
||||
" aFresnel = vec3 (theFresnel.z);\n"
|
||||
" }\n"
|
||||
"\n"
|
||||
" if (theFresnel.x > FRESNEL_CONDUCTOR)\n"
|
||||
" else if (theFresnel.x > FRESNEL_CONDUCTOR)\n"
|
||||
" {\n"
|
||||
" return vec3 (fresnelConductor (abs (theCosI), theFresnel.y, theFresnel.z));\n"
|
||||
" aFresnel = vec3 (fresnelConductor (abs (theCosI), theFresnel.y, theFresnel.z));\n"
|
||||
" }\n"
|
||||
" else\n"
|
||||
" {\n"
|
||||
" aFresnel = vec3 (fresnelDielectric (theCosI, theFresnel.y));\n"
|
||||
" }\n"
|
||||
"\n"
|
||||
" return vec3 (fresnelDielectric (theCosI, theFresnel.y));\n"
|
||||
" return aFresnel;\n"
|
||||
"}\n"
|
||||
"\n"
|
||||
"//=======================================================================\n"
|
||||
@@ -252,36 +256,34 @@ static const char Shaders_PathtraceBase_fs[] =
|
||||
" return (theWi.z <= 0.f || theWo.z <= 0.f) ? 0.f : theWi.z * (1.f / M_PI);\n"
|
||||
"}\n"
|
||||
"\n"
|
||||
"#define FLT_EPSILON 1.0e-5f\n"
|
||||
"\n"
|
||||
"//=======================================================================\n"
|
||||
"// function : SmithG1\n"
|
||||
"// purpose :\n"
|
||||
"//=======================================================================\n"
|
||||
"float SmithG1 (in vec3 theDirection, in vec3 theM, in float theRoughness)\n"
|
||||
"{\n"
|
||||
" if (dot (theDirection, theM) * theDirection.z <= 0.f)\n"
|
||||
" float aResult = 0.f;\n"
|
||||
"\n"
|
||||
" if (dot (theDirection, theM) * theDirection.z > 0.f)\n"
|
||||
" {\n"
|
||||
" return 0.f;\n"
|
||||
" float aTanThetaM = sqrt (1.f - theDirection.z * theDirection.z) / theDirection.z;\n"
|
||||
"\n"
|
||||
" if (aTanThetaM == 0.f)\n"
|
||||
" {\n"
|
||||
" aResult = 1.f;\n"
|
||||
" }\n"
|
||||
" else\n"
|
||||
" {\n"
|
||||
" float aVal = 1.f / (theRoughness * aTanThetaM);\n"
|
||||
"\n"
|
||||
" // Use rational approximation to shadowing-masking function (from Mitsuba)\n"
|
||||
" aResult = (3.535f + 2.181f * aVal) / (1.f / aVal + 2.276f + 2.577f * aVal);\n"
|
||||
" }\n"
|
||||
" }\n"
|
||||
"\n"
|
||||
" float aTanThetaM = sqrt (1.f - theDirection.z * theDirection.z) / theDirection.z;\n"
|
||||
"\n"
|
||||
" if (aTanThetaM == 0.0f)\n"
|
||||
" {\n"
|
||||
" return 1.f;\n"
|
||||
" }\n"
|
||||
"\n"
|
||||
" float aVal = 1.f / (theRoughness * aTanThetaM);\n"
|
||||
"\n"
|
||||
" if (aVal >= 1.6f)\n"
|
||||
" {\n"
|
||||
" return 1.f;\n"
|
||||
" }\n"
|
||||
"\n"
|
||||
" // Use fast and accurate rational approximation to the\n"
|
||||
" // shadowing-masking function (from Mitsuba renderer)\n"
|
||||
" float aSqr = aVal * aVal;\n"
|
||||
"\n"
|
||||
" return (3.535f * aVal + 2.181f * aSqr) / (1.f + 2.276f * aVal + 2.577f * aSqr);\n"
|
||||
" return min (aResult, 1.f);\n"
|
||||
"}\n"
|
||||
"\n"
|
||||
"//=======================================================================\n"
|
||||
@@ -309,18 +311,31 @@ static const char Shaders_PathtraceBase_fs[] =
|
||||
"}\n"
|
||||
"\n"
|
||||
"//=======================================================================\n"
|
||||
"// function : EvalMaterial\n"
|
||||
"// function : EvalBsdfLayered\n"
|
||||
"// purpose : Evaluates BSDF for specified material, with cos(N, PSI)\n"
|
||||
"//=======================================================================\n"
|
||||
"vec3 EvalMaterial (in SMaterial theBSDF, in vec3 theWi, in vec3 theWo)\n"
|
||||
"vec3 EvalBsdfLayered (in SBSDF theBSDF, in vec3 theWi, in vec3 theWo)\n"
|
||||
"{\n"
|
||||
"#ifdef TWO_SIDED_BXDF\n"
|
||||
" theWi.z *= sign (theWi.z);\n"
|
||||
" theWo.z *= sign (theWo.z);\n"
|
||||
"#endif\n"
|
||||
"\n"
|
||||
" return theBSDF.Kd.rgb * EvalLambertianReflection (theWi, theWo) +\n"
|
||||
" theBSDF.Ks.rgb * EvalBlinnReflection (theWi, theWo, theBSDF.Fresnel, theBSDF.Ks.w);\n"
|
||||
" vec3 aBxDF = theBSDF.Kd.rgb * EvalLambertianReflection (theWi, theWo);\n"
|
||||
"\n"
|
||||
" if (theBSDF.Ks.w > FLT_EPSILON)\n"
|
||||
" {\n"
|
||||
" aBxDF += theBSDF.Ks.rgb * EvalBlinnReflection (theWi, theWo, theBSDF.FresnelBase, theBSDF.Ks.w);\n"
|
||||
" }\n"
|
||||
"\n"
|
||||
" aBxDF *= UNIT - fresnelMedia (theWo.z, theBSDF.FresnelCoat);\n"
|
||||
"\n"
|
||||
" if (theBSDF.Kc.w > FLT_EPSILON)\n"
|
||||
" {\n"
|
||||
" aBxDF += theBSDF.Kc.rgb * EvalBlinnReflection (theWi, theWo, theBSDF.FresnelCoat, theBSDF.Kc.w);\n"
|
||||
" }\n"
|
||||
"\n"
|
||||
" return aBxDF;\n"
|
||||
"}\n"
|
||||
"\n"
|
||||
"//=======================================================================\n"
|
||||
@@ -352,7 +367,7 @@ static const char Shaders_PathtraceBase_fs[] =
|
||||
"}\n"
|
||||
"\n"
|
||||
"//=======================================================================\n"
|
||||
"// function : SampleBlinnReflection\n"
|
||||
"// function : SampleGlossyBlinnReflection\n"
|
||||
"// purpose : Samples Blinn BRDF, W = BRDF * cos(N, PSI) / PDF(PSI)\n"
|
||||
"// The BRDF is a product of three main terms, D, G, and F,\n"
|
||||
"// which is then divided by two cosine terms. Here we perform\n"
|
||||
@@ -361,7 +376,7 @@ static const char Shaders_PathtraceBase_fs[] =
|
||||
"// terms would be complex, and it is the D term that accounts\n"
|
||||
"// for most of the variation.\n"
|
||||
"//=======================================================================\n"
|
||||
"vec3 SampleBlinnReflection (in vec3 theWo, out vec3 theWi, in vec3 theFresnel, in float theRoughness, inout float thePDF)\n"
|
||||
"vec3 SampleGlossyBlinnReflection (in vec3 theWo, out vec3 theWi, in vec3 theFresnel, in float theRoughness, inout float thePDF)\n"
|
||||
"{\n"
|
||||
" float aKsi1 = RandFloat();\n"
|
||||
" float aKsi2 = RandFloat();\n"
|
||||
@@ -399,7 +414,7 @@ static const char Shaders_PathtraceBase_fs[] =
|
||||
" }\n"
|
||||
"\n"
|
||||
" // Jacobian of half-direction mapping\n"
|
||||
" thePDF /= 4.f * dot (theWi, aM);\n"
|
||||
" thePDF /= 4.f * aCosDelta;\n"
|
||||
"\n"
|
||||
" // compute shadow-masking coefficient\n"
|
||||
" float aG = SmithG1 (theWo, aM, theRoughness) *\n"
|
||||
@@ -414,139 +429,152 @@ static const char Shaders_PathtraceBase_fs[] =
|
||||
"}\n"
|
||||
"\n"
|
||||
"//=======================================================================\n"
|
||||
"// function : SampleSpecularReflection\n"
|
||||
"// purpose : Samples specular BRDF, W = BRDF * cos(N, PSI) / PDF(PSI)\n"
|
||||
"//=======================================================================\n"
|
||||
"vec3 SampleSpecularReflection (in vec3 theWo, out vec3 theWi, in vec3 theFresnel)\n"
|
||||
"{\n"
|
||||
" // Sample input direction\n"
|
||||
" theWi = vec3 (-theWo.x,\n"
|
||||
" -theWo.y,\n"
|
||||
" theWo.z);\n"
|
||||
"\n"
|
||||
"#ifdef TWO_SIDED_BXDF\n"
|
||||
" return fresnelMedia (theWo.z, theFresnel);\n"
|
||||
"#else\n"
|
||||
" return fresnelMedia (theWo.z, theFresnel) * step (0.f, theWo.z);\n"
|
||||
"#endif\n"
|
||||
"}\n"
|
||||
"\n"
|
||||
"//=======================================================================\n"
|
||||
"// function : SampleSpecularTransmission\n"
|
||||
"// purpose : Samples specular BTDF, W = BRDF * cos(N, PSI) / PDF(PSI)\n"
|
||||
"//=======================================================================\n"
|
||||
"vec3 SampleSpecularTransmission (in vec3 theWo, out vec3 theWi, in vec3 theWeight, in vec3 theFresnel, inout bool theInside)\n"
|
||||
"{\n"
|
||||
" vec3 aFactor = fresnelMedia (theWo.z, theFresnel);\n"
|
||||
"\n"
|
||||
" float aReflection = convolve (aFactor, theWeight);\n"
|
||||
"\n"
|
||||
" // sample specular BRDF/BTDF\n"
|
||||
" if (RandFloat() <= aReflection)\n"
|
||||
" {\n"
|
||||
" theWi = vec3 (-theWo.x,\n"
|
||||
" -theWo.y,\n"
|
||||
" theWo.z);\n"
|
||||
"\n"
|
||||
" theWeight = aFactor * (1.f / aReflection);\n"
|
||||
" }\n"
|
||||
" else\n"
|
||||
" {\n"
|
||||
" theInside = !theInside;\n"
|
||||
"\n"
|
||||
" transmitted (theFresnel.y, theWo, theWi);\n"
|
||||
"\n"
|
||||
" theWeight = (UNIT - aFactor) * (1.f / (1.f - aReflection));\n"
|
||||
" }\n"
|
||||
"\n"
|
||||
" return theWeight;\n"
|
||||
"}\n"
|
||||
"\n"
|
||||
"#define FLT_EPSILON 1.0e-5F\n"
|
||||
"\n"
|
||||
"//=======================================================================\n"
|
||||
"// function : BsdfPdf\n"
|
||||
"// function : BsdfPdfLayered\n"
|
||||
"// purpose : Calculates BSDF of sampling input knowing output\n"
|
||||
"//=======================================================================\n"
|
||||
"float BsdfPdf (in SMaterial theBSDF, in vec3 theWo, in vec3 theWi, in vec3 theWeight)\n"
|
||||
"float BsdfPdfLayered (in SBSDF theBSDF, in vec3 theWo, in vec3 theWi, in vec3 theWeight)\n"
|
||||
"{\n"
|
||||
" float aPd = convolve (theBSDF.Kd.rgb, theWeight);\n"
|
||||
" float aPs = convolve (theBSDF.Ks.rgb, theWeight);\n"
|
||||
" float aPr = convolve (theBSDF.Kr.rgb, theWeight);\n"
|
||||
" float aPt = convolve (theBSDF.Kt.rgb, theWeight);\n"
|
||||
"\n"
|
||||
" float aReflection = aPd + aPs + aPr + aPt;\n"
|
||||
"\n"
|
||||
" float aPDF = 0.f; // PDF of sampling input direction\n"
|
||||
"\n"
|
||||
" // We choose whether the light is reflected or transmitted\n"
|
||||
" // by the coating layer according to the Fresnel equations\n"
|
||||
" vec3 aCoatF = fresnelMedia (theWo.z, theBSDF.FresnelCoat);\n"
|
||||
"\n"
|
||||
" // Coat BRDF is scaled by its Fresnel reflectance term. For\n"
|
||||
" // reasons of simplicity we scale base BxDFs only by coat's\n"
|
||||
" // Fresnel transmittance term\n"
|
||||
" vec3 aCoatT = UNIT - aCoatF;\n"
|
||||
"\n"
|
||||
" float aPc = dot (theBSDF.Kc.rgb * aCoatF, theWeight);\n"
|
||||
" float aPd = dot (theBSDF.Kd.rgb * aCoatT, theWeight);\n"
|
||||
" float aPs = dot (theBSDF.Ks.rgb * aCoatT, theWeight);\n"
|
||||
" float aPt = dot (theBSDF.Kt.rgb * aCoatT, theWeight);\n"
|
||||
"\n"
|
||||
" if (theWi.z * theWo.z > 0.f)\n"
|
||||
" {\n"
|
||||
" vec3 aH = normalize (theWi + theWo);\n"
|
||||
"\n"
|
||||
" // roughness value --> Blinn exponent\n"
|
||||
" float aPower = max (2.f / (theBSDF.Ks.w * theBSDF.Ks.w) - 2.f, 0.f);\n"
|
||||
" aPDF = aPd * abs (theWi.z / M_PI);\n"
|
||||
"\n"
|
||||
" aPDF = aPd * abs (theWi.z / M_PI) +\n"
|
||||
" aPs * (aPower + 2.f) * (1.f / M_2_PI) * pow (abs (aH.z), aPower + 1.f) / (4.f * dot (theWi, aH));\n"
|
||||
" if (theBSDF.Kc.w > FLT_EPSILON)\n"
|
||||
" {\n"
|
||||
" float aPower = max (2.f / (theBSDF.Kc.w * theBSDF.Kc.w) - 2.f, 0.f); // roughness --> exponent\n"
|
||||
"\n"
|
||||
" aPDF += aPc * (aPower + 2.f) * (0.25f / M_2_PI) * pow (abs (aH.z), aPower + 1.f) / dot (theWi, aH);\n"
|
||||
" }\n"
|
||||
"\n"
|
||||
" if (theBSDF.Ks.w > FLT_EPSILON)\n"
|
||||
" {\n"
|
||||
" float aPower = max (2.f / (theBSDF.Ks.w * theBSDF.Ks.w) - 2.f, 0.f); // roughness --> exponent\n"
|
||||
"\n"
|
||||
" aPDF += aPs * (aPower + 2.f) * (0.25f / M_2_PI) * pow (abs (aH.z), aPower + 1.f) / dot (theWi, aH);\n"
|
||||
" }\n"
|
||||
" }\n"
|
||||
"\n"
|
||||
" return aPDF / aReflection;\n"
|
||||
" return aPDF / (aPc + aPd + aPs + aPt);\n"
|
||||
"}\n"
|
||||
"\n"
|
||||
"//! Tool macro to handle sampling of particular BxDF\n"
|
||||
"#define PICK_BXDF(p, k) aPDF = p / aReflection; theWeight *= k / aPDF;\n"
|
||||
"#define PICK_BXDF_LAYER(p, k) aPDF = p / aTotalR; theWeight *= k / aPDF;\n"
|
||||
"\n"
|
||||
"//=======================================================================\n"
|
||||
"// function : SampleBsdf\n"
|
||||
"// function : SampleBsdfLayered\n"
|
||||
"// purpose : Samples specified composite material (BSDF)\n"
|
||||
"//=======================================================================\n"
|
||||
"float SampleBsdf (in SMaterial theBSDF, in vec3 theWo, out vec3 theWi, inout vec3 theWeight, inout bool theInside)\n"
|
||||
"float SampleBsdfLayered (in SBSDF theBSDF, in vec3 theWo, out vec3 theWi, inout vec3 theWeight, inout bool theInside)\n"
|
||||
"{\n"
|
||||
" // compute probability of each reflection type (BxDF)\n"
|
||||
" float aPd = convolve (theBSDF.Kd.rgb, theWeight);\n"
|
||||
" float aPs = convolve (theBSDF.Ks.rgb, theWeight);\n"
|
||||
" float aPr = convolve (theBSDF.Kr.rgb, theWeight);\n"
|
||||
" float aPt = convolve (theBSDF.Kt.rgb, theWeight);\n"
|
||||
" // NOTE: OCCT uses two-layer material model. We have base diffuse, glossy, or transmissive\n"
|
||||
" // layer, covered by one glossy/specular coat. In the current model, the layers themselves\n"
|
||||
" // have no thickness; they can simply reflect light or transmits it to the layer under it.\n"
|
||||
" // We use actual BRDF model only for direct reflection by the coat layer. For transmission\n"
|
||||
" // through this layer, we approximate it as a flat specular surface.\n"
|
||||
"\n"
|
||||
" float aReflection = aPd + aPs + aPr + aPt;\n"
|
||||
" float aPDF = 0.f; // PDF of sampled direction\n"
|
||||
"\n"
|
||||
" // choose BxDF component to sample\n"
|
||||
" float aKsi = aReflection * RandFloat();\n"
|
||||
" // We choose whether the light is reflected or transmitted\n"
|
||||
" // by the coating layer according to the Fresnel equations\n"
|
||||
" vec3 aCoatF = fresnelMedia (theWo.z, theBSDF.FresnelCoat);\n"
|
||||
"\n"
|
||||
" // BxDF's PDF of sampled direction\n"
|
||||
" float aPDF = 0.f;\n"
|
||||
" // Coat BRDF is scaled by its Fresnel term. According to\n"
|
||||
" // Wilkie-Weidlich layered BSDF model, transmission term\n"
|
||||
" // for light passing through the coat at direction I and\n"
|
||||
" // leaving it in O is T = ( 1 - F (O) ) x ( 1 - F (I) ).\n"
|
||||
" // For reasons of simplicity, we discard the second term\n"
|
||||
" // and scale base BxDFs only by the first term.\n"
|
||||
" vec3 aCoatT = UNIT - aCoatF;\n"
|
||||
"\n"
|
||||
" if (aKsi < aPd) // diffuse reflection\n"
|
||||
" float aPc = dot (theBSDF.Kc.rgb * aCoatF, theWeight);\n"
|
||||
" float aPd = dot (theBSDF.Kd.rgb * aCoatT, theWeight);\n"
|
||||
" float aPs = dot (theBSDF.Ks.rgb * aCoatT, theWeight);\n"
|
||||
" float aPt = dot (theBSDF.Kt.rgb * aCoatT, theWeight);\n"
|
||||
"\n"
|
||||
" // Calculate total reflection probability\n"
|
||||
" float aTotalR = (aPc + aPd) + (aPs + aPt);\n"
|
||||
"\n"
|
||||
" // Generate random variable to select BxDF\n"
|
||||
" float aKsi = aTotalR * RandFloat();\n"
|
||||
"\n"
|
||||
" if (aKsi < aPc) // REFLECTION FROM COAT\n"
|
||||
" {\n"
|
||||
" PICK_BXDF (aPd, theBSDF.Kd.rgb);\n"
|
||||
" PICK_BXDF_LAYER (aPc, theBSDF.Kc.rgb)\n"
|
||||
"\n"
|
||||
" theWeight *= SampleLambertianReflection (theWo, theWi, aPDF);\n"
|
||||
" if (theBSDF.Kc.w < FLT_EPSILON)\n"
|
||||
" {\n"
|
||||
" theWeight *= aCoatF;\n"
|
||||
"\n"
|
||||
" theWi = vec3 (-theWo.x,\n"
|
||||
" -theWo.y,\n"
|
||||
" theWo.z);\n"
|
||||
" }\n"
|
||||
" else\n"
|
||||
" {\n"
|
||||
" theWeight *= SampleGlossyBlinnReflection (theWo, theWi, theBSDF.FresnelCoat, theBSDF.Kc.w, aPDF);\n"
|
||||
" }\n"
|
||||
"\n"
|
||||
" aPDF = mix (aPDF, MAXFLOAT, theBSDF.Kc.w < FLT_EPSILON);\n"
|
||||
" }\n"
|
||||
" else if (aKsi < aPd + aPs) // glossy reflection\n"
|
||||
" else if (aKsi < aTotalR) // REFLECTION FROM BASE\n"
|
||||
" {\n"
|
||||
" PICK_BXDF (aPs, theBSDF.Ks.rgb);\n"
|
||||
" theWeight *= aCoatT;\n"
|
||||
"\n"
|
||||
" theWeight *= SampleBlinnReflection (theWo, theWi, theBSDF.Fresnel, theBSDF.Ks.w, aPDF);\n"
|
||||
" }\n"
|
||||
" else if (aKsi < aPd + aPs + aPr) // specular reflection\n"
|
||||
" {\n"
|
||||
" PICK_BXDF (aPr, theBSDF.Kr.rgb);\n"
|
||||
" if (aKsi < aPc + aPd) // diffuse BRDF\n"
|
||||
" {\n"
|
||||
" PICK_BXDF_LAYER (aPd, theBSDF.Kd.rgb)\n"
|
||||
"\n"
|
||||
" aPDF = MAXFLOAT;\n"
|
||||
" theWeight *= SampleLambertianReflection (theWo, theWi, aPDF);\n"
|
||||
" }\n"
|
||||
" else if (aKsi < (aPc + aPd) + aPs) // specular/glossy BRDF\n"
|
||||
" {\n"
|
||||
" PICK_BXDF_LAYER (aPs, theBSDF.Ks.rgb)\n"
|
||||
"\n"
|
||||
" theWeight *= SampleSpecularReflection (theWo, theWi, theBSDF.Fresnel);\n"
|
||||
" }\n"
|
||||
" else if (aKsi < aReflection) // specular transmission\n"
|
||||
" {\n"
|
||||
" PICK_BXDF (aPt, theBSDF.Kt.rgb);\n"
|
||||
" if (theBSDF.Ks.w < FLT_EPSILON)\n"
|
||||
" {\n"
|
||||
" theWeight *= fresnelMedia (theWo.z, theBSDF.FresnelBase);\n"
|
||||
"\n"
|
||||
" aPDF = MAXFLOAT;\n"
|
||||
" theWi = vec3 (-theWo.x,\n"
|
||||
" -theWo.y,\n"
|
||||
" theWo.z);\n"
|
||||
" }\n"
|
||||
" else\n"
|
||||
" {\n"
|
||||
" theWeight *= SampleGlossyBlinnReflection (theWo, theWi, theBSDF.FresnelBase, theBSDF.Ks.w, aPDF);\n"
|
||||
" }\n"
|
||||
"\n"
|
||||
" theWeight *= SampleSpecularTransmission (theWo, theWi, theWeight, theBSDF.Fresnel, theInside);\n"
|
||||
" aPDF = mix (aPDF, MAXFLOAT, theBSDF.Ks.w < FLT_EPSILON);\n"
|
||||
" }\n"
|
||||
" else // specular transmission\n"
|
||||
" {\n"
|
||||
" PICK_BXDF_LAYER (aPt, theBSDF.Kt.rgb)\n"
|
||||
"\n"
|
||||
" // refracted direction should exist if we are here\n"
|
||||
" transmitted (theBSDF.FresnelCoat.y, theWo, theWi);\n"
|
||||
"\n"
|
||||
" theInside = !theInside; aPDF = MAXFLOAT;\n"
|
||||
" }\n"
|
||||
" }\n"
|
||||
"\n"
|
||||
" // path termination for extra small weights\n"
|
||||
" theWeight = mix (ZERO, theWeight, step (FLT_EPSILON, aReflection));\n"
|
||||
" theWeight = mix (ZERO, theWeight, step (FLT_EPSILON, aTotalR));\n"
|
||||
"\n"
|
||||
" return aPDF;\n"
|
||||
"}\n"
|
||||
@@ -692,15 +720,16 @@ static const char Shaders_PathtraceBase_fs[] =
|
||||
"#define MIN_THROUGHPUT vec3 (1.0e-3f)\n"
|
||||
"#define MIN_CONTRIBUTION vec3 (1.0e-2f)\n"
|
||||
"\n"
|
||||
"#define MATERIAL_KD(index) (18 * index + 11)\n"
|
||||
"#define MATERIAL_KR(index) (18 * index + 12)\n"
|
||||
"#define MATERIAL_KT(index) (18 * index + 13)\n"
|
||||
"#define MATERIAL_KS(index) (18 * index + 14)\n"
|
||||
"#define MATERIAL_LE(index) (18 * index + 15)\n"
|
||||
"#define MATERIAL_FRESNEL(index) (18 * index + 16)\n"
|
||||
"#define MATERIAL_ABSORPT(index) (18 * index + 17)\n"
|
||||
"#define MATERIAL_KC(index) (19 * index + 11)\n"
|
||||
"#define MATERIAL_KD(index) (19 * index + 12)\n"
|
||||
"#define MATERIAL_KS(index) (19 * index + 13)\n"
|
||||
"#define MATERIAL_KT(index) (19 * index + 14)\n"
|
||||
"#define MATERIAL_LE(index) (19 * index + 15)\n"
|
||||
"#define MATERIAL_FRESNEL_COAT(index) (19 * index + 16)\n"
|
||||
"#define MATERIAL_FRESNEL_BASE(index) (19 * index + 17)\n"
|
||||
"#define MATERIAL_ABSORPT_BASE(index) (19 * index + 18)\n"
|
||||
"\n"
|
||||
"//! Enables experimental russian roulette sampling path termination.\n"
|
||||
"//! Enables experimental Russian roulette sampling path termination.\n"
|
||||
"//! In most cases, it provides faster image convergence with minimal\n"
|
||||
"//! bias, so it is enabled by default.\n"
|
||||
"#define RUSSIAN_ROULETTE\n"
|
||||
@@ -716,6 +745,18 @@ static const char Shaders_PathtraceBase_fs[] =
|
||||
"#endif\n"
|
||||
"\n"
|
||||
"//=======================================================================\n"
|
||||
"// function : IsNotZero\n"
|
||||
"// purpose : Checks whether BSDF reflects direct light\n"
|
||||
"//=======================================================================\n"
|
||||
"bool IsNotZero (in SBSDF theBSDF, in vec3 theThroughput)\n"
|
||||
"{\n"
|
||||
" vec3 aGlossy = theBSDF.Kc.rgb * step (FLT_EPSILON, theBSDF.Kc.w) +\n"
|
||||
" theBSDF.Ks.rgb * step (FLT_EPSILON, theBSDF.Ks.w);\n"
|
||||
"\n"
|
||||
" return convolve (theBSDF.Kd.rgb + aGlossy, theThroughput) > FLT_EPSILON;\n"
|
||||
"}\n"
|
||||
"\n"
|
||||
"//=======================================================================\n"
|
||||
"// function : PathTrace\n"
|
||||
"// purpose : Calculates radiance along the given ray\n"
|
||||
"//=======================================================================\n"
|
||||
@@ -769,17 +810,25 @@ static const char Shaders_PathtraceBase_fs[] =
|
||||
" aRaytraceDepth = (aNDCPoint.z / aNDCPoint.w + aPolygonOffset * POLYGON_OFFSET_SCALE) * 0.5f + 0.5f;\n"
|
||||
" }\n"
|
||||
"\n"
|
||||
" // fetch material (BSDF)\n"
|
||||
" SMaterial aMaterial = SMaterial (\n"
|
||||
" vec4 (texelFetch (uRaytraceMaterialTexture, MATERIAL_KD (aTriIndex.w))),\n"
|
||||
" vec3 (texelFetch (uRaytraceMaterialTexture, MATERIAL_KR (aTriIndex.w))),\n"
|
||||
" vec3 (texelFetch (uRaytraceMaterialTexture, MATERIAL_KT (aTriIndex.w))),\n"
|
||||
" vec4 (texelFetch (uRaytraceMaterialTexture, MATERIAL_KS (aTriIndex.w))),\n"
|
||||
" vec3 (texelFetch (uRaytraceMaterialTexture, MATERIAL_FRESNEL (aTriIndex.w))),\n"
|
||||
" vec4 (texelFetch (uRaytraceMaterialTexture, MATERIAL_ABSORPT (aTriIndex.w))));\n"
|
||||
" SBSDF aBSDF;\n"
|
||||
"\n"
|
||||
" // fetch BxDF weights\n"
|
||||
" aBSDF.Kc = texelFetch (uRaytraceMaterialTexture, MATERIAL_KC (aTriIndex.w));\n"
|
||||
" aBSDF.Kd = texelFetch (uRaytraceMaterialTexture, MATERIAL_KD (aTriIndex.w));\n"
|
||||
" aBSDF.Ks = texelFetch (uRaytraceMaterialTexture, MATERIAL_KS (aTriIndex.w));\n"
|
||||
" aBSDF.Kt = texelFetch (uRaytraceMaterialTexture, MATERIAL_KT (aTriIndex.w)).rgb;\n"
|
||||
"\n"
|
||||
" // compute smooth normal (in parallel with fetch)\n"
|
||||
" vec3 aNormal = SmoothNormal (aHit.UV, aTriIndex);\n"
|
||||
"\n"
|
||||
" aNormal = normalize (vec3 (dot (aInvTransf0, aNormal),\n"
|
||||
" dot (aInvTransf1, aNormal),\n"
|
||||
" dot (aInvTransf2, aNormal)));\n"
|
||||
"\n"
|
||||
" SLocalSpace aSpace = buildLocalSpace (aNormal);\n"
|
||||
"\n"
|
||||
"#ifdef USE_TEXTURES\n"
|
||||
" if (aMaterial.Kd.w >= 0.f)\n"
|
||||
" if (aBSDF.Kd.w >= 0.f)\n"
|
||||
" {\n"
|
||||
" vec4 aTexCoord = vec4 (SmoothUV (aHit.UV, aTriIndex), 0.f, 1.f);\n"
|
||||
"\n"
|
||||
@@ -792,32 +841,23 @@ static const char Shaders_PathtraceBase_fs[] =
|
||||
" dot (aTrsfRow2, aTexCoord));\n"
|
||||
"\n"
|
||||
" vec4 aTexColor = textureLod (\n"
|
||||
" sampler2D (uTextureSamplers[int (aMaterial.Kd.w)]), aTexCoord.st, 0.f);\n"
|
||||
" sampler2D (uTextureSamplers[int (aBSDF.Kd.w)]), aTexCoord.st, 0.f);\n"
|
||||
"\n"
|
||||
" aMaterial.Kd.rgb *= (aTexColor.rgb * aTexColor.rgb) * aTexColor.w; // de-gamma correction (for gamma = 2)\n"
|
||||
" aBSDF.Kd.rgb *= (aTexColor.rgb * aTexColor.rgb) * aTexColor.w; // de-gamma correction (for gamma = 2)\n"
|
||||
"\n"
|
||||
" if (aTexColor.w != 1.0f)\n"
|
||||
" {\n"
|
||||
" // mix transparency BTDF with texture alpha-channel\n"
|
||||
" aMaterial.Kt = (UNIT - aTexColor.www) + aTexColor.w * aMaterial.Kt;\n"
|
||||
" aBSDF.Kt = (UNIT - aTexColor.www) + aTexColor.w * aBSDF.Kt;\n"
|
||||
" }\n"
|
||||
" }\n"
|
||||
"#endif\n"
|
||||
"\n"
|
||||
" // compute smooth normal\n"
|
||||
" vec3 aNormal = SmoothNormal (aHit.UV, aTriIndex);\n"
|
||||
" // fetch Fresnel reflectance for both layers\n"
|
||||
" aBSDF.FresnelCoat = texelFetch (uRaytraceMaterialTexture, MATERIAL_FRESNEL_COAT (aTriIndex.w)).xyz;\n"
|
||||
" aBSDF.FresnelBase = texelFetch (uRaytraceMaterialTexture, MATERIAL_FRESNEL_BASE (aTriIndex.w)).xyz;\n"
|
||||
"\n"
|
||||
" aNormal = normalize (vec3 (dot (aInvTransf0, aNormal),\n"
|
||||
" dot (aInvTransf1, aNormal),\n"
|
||||
" dot (aInvTransf2, aNormal)));\n"
|
||||
"\n"
|
||||
" SLocalSpace aSpace = buildLocalSpace (aNormal);\n"
|
||||
"\n"
|
||||
" // account for self-emission (not stored in the material)\n"
|
||||
" aRadiance += aThroughput * texelFetch (\n"
|
||||
" uRaytraceMaterialTexture, MATERIAL_LE (aTriIndex.w)).rgb;\n"
|
||||
"\n"
|
||||
" if (uLightCount > 0 && convolve (aMaterial.Kd.rgb + aMaterial.Ks.rgb, aThroughput) > 0.f)\n"
|
||||
" if (uLightCount > 0 && IsNotZero (aBSDF, aThroughput))\n"
|
||||
" {\n"
|
||||
" aExpPDF = 1.f / uLightCount;\n"
|
||||
"\n"
|
||||
@@ -836,14 +876,14 @@ static const char Shaders_PathtraceBase_fs[] =
|
||||
" aLight.xyz = SampleLight (aLight.xyz, aDistance,\n"
|
||||
" aLight.w == 0.f /* is infinite */, aParam.w /* max cos or radius */, aExpPDF);\n"
|
||||
"\n"
|
||||
" aImpPDF = BsdfPdf (aMaterial,\n"
|
||||
" aImpPDF = BsdfPdfLayered (aBSDF,\n"
|
||||
" toLocalSpace (-theRay.Direct, aSpace), toLocalSpace (aLight.xyz, aSpace), aThroughput);\n"
|
||||
"\n"
|
||||
" // MIS weight including division by explicit PDF\n"
|
||||
" float aMIS = (aExpPDF == MAXFLOAT) ? 1.f : aExpPDF / (aExpPDF * aExpPDF + aImpPDF * aImpPDF);\n"
|
||||
"\n"
|
||||
" vec3 aContrib = aMIS * aParam.rgb /* Le */ * EvalMaterial (\n"
|
||||
" aMaterial, toLocalSpace (aLight.xyz, aSpace), toLocalSpace (-theRay.Direct, aSpace));\n"
|
||||
" vec3 aContrib = aMIS * aParam.rgb /* Le */ * EvalBsdfLayered (\n"
|
||||
" aBSDF, toLocalSpace (aLight.xyz, aSpace), toLocalSpace (-theRay.Direct, aSpace));\n"
|
||||
"\n"
|
||||
" if (any (greaterThan (aContrib, MIN_CONTRIBUTION))) // check if light source is important\n"
|
||||
" {\n"
|
||||
@@ -855,25 +895,29 @@ static const char Shaders_PathtraceBase_fs[] =
|
||||
" float aVisibility = SceneAnyHit (aShadow,\n"
|
||||
" InverseDirection (aLight.xyz), aLight.w == 0.f ? MAXFLOAT : aDistance);\n"
|
||||
"\n"
|
||||
" aRadiance += aVisibility * aThroughput * aContrib;\n"
|
||||
" aRadiance += aVisibility * (aThroughput * aContrib);\n"
|
||||
" }\n"
|
||||
" }\n"
|
||||
"\n"
|
||||
" // account for self-emission\n"
|
||||
" aRadiance += aThroughput * texelFetch (uRaytraceMaterialTexture, MATERIAL_LE (aTriIndex.w)).rgb;\n"
|
||||
"\n"
|
||||
" if (aInMedium) // handle attenuation\n"
|
||||
" {\n"
|
||||
" aThroughput *= exp (-aHit.Time *\n"
|
||||
" aMaterial.Absorption.w * (UNIT - aMaterial.Absorption.rgb));\n"
|
||||
" vec4 aScattering = texelFetch (uRaytraceMaterialTexture, MATERIAL_ABSORPT_BASE (aTriIndex.w));\n"
|
||||
"\n"
|
||||
" aThroughput *= exp (-aHit.Time * aScattering.w * (UNIT - aScattering.rgb));\n"
|
||||
" }\n"
|
||||
"\n"
|
||||
" vec3 anInput = UNIT; // sampled input direction\n"
|
||||
"\n"
|
||||
" aImpPDF = SampleBsdf (aMaterial,\n"
|
||||
" aImpPDF = SampleBsdfLayered (aBSDF,\n"
|
||||
" toLocalSpace (-theRay.Direct, aSpace), anInput, aThroughput, aInMedium);\n"
|
||||
"\n"
|
||||
" float aSurvive = 1.f;\n"
|
||||
" float aSurvive = float (any (greaterThan (aThroughput, MIN_THROUGHPUT)));\n"
|
||||
"\n"
|
||||
"#ifdef RUSSIAN_ROULETTE\n"
|
||||
" aSurvive = aDepth < 3 ? 1.f : min (dot (LUMA, aThroughput), 0.95f);\n"
|
||||
" aSurvive = aDepth < 3 ? aSurvive : min (dot (LUMA, aThroughput), 0.95f);\n"
|
||||
"#endif\n"
|
||||
"\n"
|
||||
" // here, we additionally increase path length for non-diffuse bounces\n"
|
||||
|
||||
@@ -356,16 +356,16 @@ static const char Shaders_RaytraceBase_fs[] =
|
||||
" ivec4 SubData;\n"
|
||||
"};\n"
|
||||
"\n"
|
||||
"#define MATERIAL_AMBN(index) (18 * index + 0)\n"
|
||||
"#define MATERIAL_DIFF(index) (18 * index + 1)\n"
|
||||
"#define MATERIAL_SPEC(index) (18 * index + 2)\n"
|
||||
"#define MATERIAL_EMIS(index) (18 * index + 3)\n"
|
||||
"#define MATERIAL_REFL(index) (18 * index + 4)\n"
|
||||
"#define MATERIAL_REFR(index) (18 * index + 5)\n"
|
||||
"#define MATERIAL_TRAN(index) (18 * index + 6)\n"
|
||||
"#define MATERIAL_TRS1(index) (18 * index + 7)\n"
|
||||
"#define MATERIAL_TRS2(index) (18 * index + 8)\n"
|
||||
"#define MATERIAL_TRS3(index) (18 * index + 9)\n"
|
||||
"#define MATERIAL_AMBN(index) (19 * index + 0)\n"
|
||||
"#define MATERIAL_DIFF(index) (19 * index + 1)\n"
|
||||
"#define MATERIAL_SPEC(index) (19 * index + 2)\n"
|
||||
"#define MATERIAL_EMIS(index) (19 * index + 3)\n"
|
||||
"#define MATERIAL_REFL(index) (19 * index + 4)\n"
|
||||
"#define MATERIAL_REFR(index) (19 * index + 5)\n"
|
||||
"#define MATERIAL_TRAN(index) (19 * index + 6)\n"
|
||||
"#define MATERIAL_TRS1(index) (19 * index + 7)\n"
|
||||
"#define MATERIAL_TRS2(index) (19 * index + 8)\n"
|
||||
"#define MATERIAL_TRS3(index) (19 * index + 9)\n"
|
||||
"\n"
|
||||
"#define TRS_OFFSET(treelet) treelet.SubData.x\n"
|
||||
"#define BVH_OFFSET(treelet) treelet.SubData.y\n"
|
||||
|
||||
Reference in New Issue
Block a user