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Assets/ScriptableRenderLoop/ShaderLibrary/ImageBasedLighting.hlsl

 
         if (!prefilter) // BRDF importance sampling
         {
-            mipLevel = 0.0;
+            mipLevel = 0;
         }
         else // Prefiltered BRDF importance sampling
         {
 
             float invPdf    = D_GGX_Inverse(NdotH, roughness) * 4.0;
             // TODO: check the accuracy of the sample's solid angle fit for GGX.
-            float omegaS    = rcp(sampleCount) * invPdf;      // Solid angle associated with the sample
+            float omegaS    = rcp(sampleCount) * invPdf;
-            // float omegaP = FOUR_PI / (6.0f * cubemapWidth * cubemapWidth); // Solid angle associated with the pixel of the cubemap
-            mipLevel        = 0.5 * log2(omegaS * invOmegaP); // Clamp is not necessary as the hardware will do it
+            // float omegaP = FOUR_PI / (6.0f * cubemapWidth * cubemapWidth);
+            mipLevel        = 0.5 * log2(omegaS * invOmegaP);
+            // TODO: find a more accurate MIP bias function.
             mipLevel = lerp(mipLevel, maxMipLevel, bias);
         }