Use overlay formula for albedo and smoothness detail map

ScriptableRenderPipeline/HDRenderPipeline/Material/Lit/LitDataInternal.hlsl

-void ADD_IDX(ComputeLayerTexCoord)( // Uv related parameters
+void ADD_IDX(ComputeLayerTexCoord)( // Uv related parameters
                                     float2 texCoord0, float2 texCoord1, float2 texCoord2, float2 texCoord3, float4 uvMappingMask, float4 uvMappingMaskDetails,
                                     // scale and bias for base and detail + global tiling factor (for layered lit only)
                                     float2 texScale, float2 texBias, float2 texScaleDetails, float2 texBiasDetails, float additionalTiling,
 
     surfaceData.baseColor = SAMPLE_UVMAPPING_TEXTURE2D(ADD_IDX(_BaseColorMap), ADD_ZERO_IDX(sampler_BaseColorMap), ADD_IDX(layerTexCoord.base)).rgb * ADD_IDX(_BaseColor).rgb;
 #ifdef _DETAIL_MAP_IDX
-    surfaceData.baseColor *= LerpWhiteTo(2.0 * detailAlbedo, detailMask * ADD_IDX(_DetailAlbedoScale));
-    // we saturate to avoid to have a smoothness value above 1
-    surfaceData.baseColor = saturate(surfaceData.baseColor);
+    // Use overlay blend mode for detail abledo: (base < 0.5 ? (2.0 * base * blend) : (1.0 - 2.0 * (1.0 - base) * (1.0 - blend)))
+    float baseColorOverlay = (detailAlbedo < 0.5) ? 
+                                surfaceData.baseColor * PositivePow(2.0 * detailAlbedo, ADD_IDX(_DetailAlbedoScale)) :
+                                1.0 - 2.0 * (1.0 - surfaceData.baseColor) * (1.0 - (detailAlbedo * ADD_IDX(_DetailAlbedoScale)));
+    // Lerp with details mask
+    surfaceData.baseColor = lerp(surfaceData.baseColor, saturate(baseColorOverlay), detailMask);
 #endif
 
     surfaceData.specularOcclusion = 1.0; // Will be setup outside of this function
 #endif
 
 #ifdef _DETAIL_MAP_IDX
-    surfaceData.perceptualSmoothness *= LerpWhiteTo(2.0 * detailSmoothness, detailMask * ADD_IDX(_DetailSmoothnessScale));
-    // we saturate to avoid to have a smoothness value above 1
-    surfaceData.perceptualSmoothness = saturate(surfaceData.perceptualSmoothness);
+    // Use overlay blend mode for detail abledo: (base < 0.5 ? (2.0 * base * blend) : (1.0 - 2.0 * (1.0 - base) * (1.0 - blend)))
+    float smoothnessOverlay = (detailSmoothness < 0.5) ?
+                                surfaceData.perceptualSmoothness * PositivePow(2.0 * detailSmoothness, ADD_IDX(_DetailSmoothnessScale)) :
+                                1.0 - 2.0 * (1.0 - surfaceData.baseColor) * (1.0 - (detailSmoothness * ADD_IDX(_DetailSmoothnessScale)));
+    // Lerp with details mask
+    surfaceData.perceptualSmoothness = lerp(surfaceData.perceptualSmoothness, saturate(smoothnessOverlay), detailMask);
 #endif
 
     // MaskMap is RGBA: Metallic, Ambient Occlusion (Optional), emissive Mask (Optional), Smoothness