fix: specular anti aliasing value (#773)

* fix: specular anti aliasing
galacean · Apr 29, 2022 · fa94637 · fa94637
1 parent e514013
commit fa94637
Showing 1 changed file with 5 additions and 2 deletions.
diff --git a/packages/core/src/shaderlib/pbr/pbr_helper.glsl b/packages/core/src/shaderlib/pbr/pbr_helper.glsl
@@ -6,9 +6,12 @@ float computeSpecularOcclusion(float ambientOcclusion, float roughness, float do
 }
 
 float getAARoughnessFactor(vec3 normal) {
+    // Kaplanyan 2016, "Stable specular highlights"
+    // Tokuyoshi 2017, "Error Reduction and Simplification for Shading Anti-Aliasing"
+    // Tokuyoshi and Kaplanyan 2019, "Improved Geometric Specular Antialiasing"
     #ifdef HAS_DERIVATIVES
         vec3 dxy = max( abs(dFdx(normal)), abs(dFdy(normal)) );
-        return max( max(dxy.x, dxy.y), dxy.z );
+        return 0.04 + max( max(dxy.x, dxy.y), dxy.z );
     #else
         return 0.04;
     #endif
@@ -117,4 +120,4 @@ void initMaterial(out Material material, const in Geometry geometry){
 // direct + indirect
 #include <brdf>
 #include <direct_irradiance_frag_define>
-#include <ibl_frag_define>
+#include <ibl_frag_define>