Merge pull request #619 from EvgeniiG/master

Reintroduce EvaluateBSDF_Area()

ScriptableRenderPipeline/Core/ShaderLibrary/Common.hlsl

     float3 positionWS;  // World space position (could be camera-relative)
     float2 positionNDC; // Normalized screen UVs          : [0, 1) (with the half-pixel offset)
     uint2  positionSS;  // Screen space pixel coordinates : [0, NumPixels)
-    uint2  tileCoord;   // Screen space tile coordinates  : [0, NumTiles)
-    float  deviceDepth; // Depth from the depth buffer    : [0, 1]
+    uint2  tileCoord;   // Screen tile coordinates        : [0, NumTiles)
+    float  deviceDepth; // Depth from the depth buffer    : [0, 1] (typically reversed)
     float  linearDepth; // View space Z coordinate        : [Near, Far]
 };
 

ScriptableRenderPipeline/HDRenderPipeline/Lighting/TilePass/TilePassLoop.hlsl

 
             while (i <= last && lightData.lightType == GPULIGHTTYPE_LINE)
             {
-                DirectLighting lighting = EvaluateBSDF_Line(context, V, posInput, preLightData, lightData, bsdfData, bakeLightingData);
+                lightData.lightType = GPULIGHTTYPE_LINE; // Enforce constant propagation
+
+                DirectLighting lighting = EvaluateBSDF_Area(context, V, posInput, preLightData, lightData, bsdfData, bakeLightingData);
                 AccumulateDirectLighting(lighting, aggregateLighting);
 
                 lightData = FetchLight(lightStart, min(++i, last));
             {
-                DirectLighting lighting = EvaluateBSDF_Rect(context, V, posInput, preLightData, lightData, bsdfData, bakeLightingData);
+                lightData.lightType = GPULIGHTTYPE_RECTANGLE; // Enforce constant propagation
+
+                DirectLighting lighting = EvaluateBSDF_Area(context, V, posInput, preLightData, lightData, bsdfData, bakeLightingData);
                 AccumulateDirectLighting(lighting, aggregateLighting);
 
                 lightData = FetchLight(lightStart, min(++i, last));

ScriptableRenderPipeline/HDRenderPipeline/Material/Lit/Lit.hlsl

     return lighting;
 }
 
+DirectLighting EvaluateBSDF_Area(LightLoopContext lightLoopContext,
+                                 float3 V, PositionInputs posInput,
+                                 PreLightData preLightData, LightData lightData,
+                                 BSDFData bsdfData, BakeLightingData bakeLightingData)
+{
+    if (lightData.lightType == GPULIGHTTYPE_LINE)
+    {
+        return EvaluateBSDF_Line(lightLoopContext, V, posInput, preLightData, lightData, bsdfData, bakeLightingData);
+    }
+    else
+    {
+        return EvaluateBSDF_Rect(lightLoopContext, V, posInput, preLightData, lightData, bsdfData, bakeLightingData);
+    }
+}
+
 //-----------------------------------------------------------------------------
 // EvaluateBSDF_Env
 // ----------------------------------------------------------------------------