fix: sheen

galacean · Dec 11, 2024 · a794dc6 · a794dc6
1 parent b9874f2
commit a794dc6
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Showing 5 changed files with 11 additions and 12 deletions.
diff --git a/packages/shaderlab/src/shaders/shadingPBR/BRDF.glsl b/packages/shaderlab/src/shaders/shadingPBR/BRDF.glsl
@@ -81,6 +81,7 @@ struct BRDFData{
     #ifdef MATERIAL_ENABLE_SHEEN
         float sheenRoughness;
         float sheenScaling;
+        float IBLsheenDFG;
     #endif
 
 };
@@ -372,10 +373,8 @@ void initBRDFData(SurfaceData surfaceData, out BRDFData brdfData){
 
     #ifdef MATERIAL_ENABLE_SHEEN
         brdfData.sheenRoughness = max(MIN_PERCEPTUAL_ROUGHNESS, min(surfaceData.sheenRoughness + getAARoughnessFactor(surfaceData.normal), 1.0));
-        // sheen energy compensation approximation calculation in ‘Sheen DFG LUT integrated over diffuse IBL’
-        // https://drive.google.com/file/d/1T0D1VSyR4AllqIJTQAraEIzjlb5h4FKH/view?usp=sharing
-        float IBLSheenDFG = IBLSheenDFG(surfaceData, brdfData.sheenRoughness);
-        brdfData.sheenScaling = 1.0 - IBLSheenDFG * max(max(surfaceData.sheenColor.r, surfaceData.sheenColor.g), surfaceData.sheenColor.b);
+        brdfData.IBLsheenDFG = IBLSheenDFG(surfaceData, brdfData.sheenRoughness);
+        brdfData.sheenScaling = 1.0 - brdfData.IBLsheenDFG * max(max(surfaceData.sheenColor.r, surfaceData.sheenColor.g), surfaceData.sheenColor.b);
     #endif
 }
 

diff --git a/packages/shaderlab/src/shaders/shadingPBR/LightDirectPBR.glsl b/packages/shaderlab/src/shaders/shadingPBR/LightDirectPBR.glsl
@@ -15,7 +15,7 @@
     #define FUNCTION_CLEAR_COAT_LOBE clearCoatLobe
 #endif
 #ifndef FUNCTION_SHEEN_LOBE
-    #define FUNCTION_SHEEN_LOBE SheenLobe
+    #define FUNCTION_SHEEN_LOBE sheenLobe
 #endif
 
 #include "BRDF.glsl"

diff --git a/packages/shaderlab/src/shaders/shadingPBR/LightIndirectFunctions.glsl b/packages/shaderlab/src/shaders/shadingPBR/LightIndirectFunctions.glsl
@@ -70,12 +70,12 @@ vec3 getLightProbeRadiance(SurfaceData surfaceData, vec3 normal, float roughness
 // This is a curve-fit approxmation to the "Charlie sheen" BRDF integrated over the hemisphere from
 // Estevez and Kulla 2017, "Production Friendly Microfacet Sheen BRDF". The analysis can be found
 // in the Sheen section of https://drive.google.com/file/d/1T0D1VSyR4AllqIJTQAraEIzjlb5h4FKH/view?usp=sharing
-float IBLSheenDFG(SurfaceData surfaceData, float roughness) {
+float IBLSheenDFG(SurfaceData surfaceData, float sheenRoughness) {
     float dotNV = surfaceData.dotNV;
-    float r2 = roughness * roughness;
-    float a = roughness < 0.25 ? -339.2 * r2 + 161.4 * roughness - 25.9 : -8.48 * r2 + 14.3 * roughness - 9.95;
-    float b = roughness < 0.25 ? 44.0 * r2 - 23.7 * roughness + 3.26 : 1.97 * r2 - 3.27 * roughness + 0.72;
-    float DG = exp( a * dotNV + b ) + ( roughness < 0.25 ? 0.0 : 0.1 * ( roughness - 0.25 ) );
+    float r2 = sheenRoughness * sheenRoughness;
+    float a = sheenRoughness < 0.25 ? -339.2 * r2 + 161.4 * sheenRoughness - 25.9 : -8.48 * r2 + 14.3 * sheenRoughness - 9.95;
+    float b = sheenRoughness < 0.25 ? 44.0 * r2 - 23.7 * sheenRoughness + 3.26 : 1.97 * r2 - 3.27 * sheenRoughness + 0.72;
+    float DG = exp( a * dotNV + b ) + ( sheenRoughness < 0.25 ? 0.0 : 0.1 * ( sheenRoughness - 0.25 ) );
     return saturate( DG * RECIPROCAL_PI );
 }
 

diff --git a/packages/shaderlab/src/shaders/shadingPBR/LightIndirectPBR.glsl b/packages/shaderlab/src/shaders/shadingPBR/LightIndirectPBR.glsl
@@ -84,7 +84,7 @@ void evaluateSheenIBL(Varyings varyings, SurfaceData surfaceData, BRDFData brdfD
         diffuseColor *= brdfData.sheenScaling;
         specularColor *= brdfData.sheenScaling;
 
-        vec3 reflectance = radianceAttenuation * IBLSheenDFG(surfaceData, brdfData.sheenRoughness) * surfaceData.sheenColor;
+        vec3 reflectance = radianceAttenuation * brdfData.IBLsheenDFG * surfaceData.sheenColor;
         specularColor += reflectance;
     #endif
 }

diff --git a/packages/shaderlab/src/shaders/shadingPBR/ReflectionLobe.glsl b/packages/shaderlab/src/shaders/shadingPBR/ReflectionLobe.glsl
@@ -9,7 +9,7 @@ void specularLobe(Varyings varyings, SurfaceData surfaceData, BRDFData brdfData,
         specularColor += attenuationIrradiance *  BRDF_Specular_GGX( incidentDirection, surfaceData, brdfData, surfaceData.normal, brdfData.specularColor, brdfData.roughness);
 }
 
-void SheenLobe(Varyings varyings, SurfaceData surfaceData, BRDFData brdfData, vec3 incidentDirection, vec3 attenuationIrradiance, inout vec3 diffuseColor, inout vec3 specularColor){
+void sheenLobe(Varyings varyings, SurfaceData surfaceData, BRDFData brdfData, vec3 incidentDirection, vec3 attenuationIrradiance, inout vec3 diffuseColor, inout vec3 specularColor){
     #ifdef MATERIAL_ENABLE_SHEEN
         diffuseColor *= brdfData.sheenScaling;
         specularColor *= brdfData.sheenScaling;