Fix POM node not working with subgraphs

com.unity.render-pipelines.core/ShaderLibrary/PerPixelDisplacement.hlsl

@@ -6,13 +6,22 @@
 // it return the offset to apply to the UVSet provide in PerPixelHeightDisplacementParam
 // viewDirTS is view vector in texture space matching the UVSet
 // ref: https://www.gamedev.net/resources/_/technical/graphics-programming-and-theory/a-closer-look-at-parallax-occlusion-mapping-r3262
+
+#ifndef POM_USER_DATA_PARAMETERS
+    #define POM_USER_DATA_PARAMETERS
+#endif
+
+#ifndef POM_USER_DATA_ARGUMENTS
+    #define POM_USER_DATA_ARGUMENTS
+#endif
+
 real2
 #ifdef POM_NAME_ID
 MERGE_NAME(ParallaxOcclusionMapping,POM_NAME_ID)
 #else
 ParallaxOcclusionMapping
 #endif
-(real lod, real lodThreshold, int numSteps, real3 viewDirTS, PerPixelHeightDisplacementParam ppdParam, out real outHeight)
+(real lod, real lodThreshold, int numSteps, real3 viewDirTS, PerPixelHeightDisplacementParam ppdParam, out real outHeight POM_USER_DATA_PARAMETERS)
 {
     // Convention: 1.0 is top, 0.0 is bottom - POM is always inward, no extrusion
     real stepSize = 1.0 / (real)numSteps;
@@ -28,9 +37,9 @@ ParallaxOcclusionMapping
 
     // Do a first step before the loop to init all value correctly
     real2 texOffsetCurrent = real2(0.0, 0.0);
-    real prevHeight = ComputePerPixelHeightDisplacement(texOffsetCurrent, lod, ppdParam);
+    real prevHeight = ComputePerPixelHeightDisplacement(texOffsetCurrent, lod, ppdParam POM_USER_DATA_ARGUMENTS);
     texOffsetCurrent += texOffsetPerStep;
-    real currHeight = ComputePerPixelHeightDisplacement(texOffsetCurrent, lod, ppdParam);
+    real currHeight = ComputePerPixelHeightDisplacement(texOffsetCurrent, lod, ppdParam POM_USER_DATA_ARGUMENTS);
     real rayHeight = 1.0 - stepSize; // Start at top less one sample
 
     // Linear search
@@ -45,7 +54,7 @@ ParallaxOcclusionMapping
         texOffsetCurrent += texOffsetPerStep;
 
         // Sample height map which in this case is stored in the alpha channel of the normal map:
-        currHeight = ComputePerPixelHeightDisplacement(texOffsetCurrent, lod, ppdParam);
+        currHeight = ComputePerPixelHeightDisplacement(texOffsetCurrent, lod, ppdParam POM_USER_DATA_ARGUMENTS);
     }
 
     // Found below and above points, now perform line interesection (ray) with piecewise linear heightfield approximation
@@ -71,7 +80,7 @@ ParallaxOcclusionMapping
         // Retrieve offset require to find this intersectionHeight
         offset = (1 - intersectionHeight) * texOffsetPerStep * numSteps;
 
-        currHeight = ComputePerPixelHeightDisplacement(offset, lod, ppdParam);
+        currHeight = ComputePerPixelHeightDisplacement(offset, lod, ppdParam POM_USER_DATA_ARGUMENTS);
 
         delta = intersectionHeight - currHeight;
 
@@ -106,7 +115,7 @@ ParallaxOcclusionMapping
     real ratio = delta0 / (delta0 + delta1);
     real2 offset = texOffsetCurrent - ratio * texOffsetPerStep;
 
-    currHeight = ComputePerPixelHeightDisplacement(offset, lod, ppdParam);
+    currHeight = ComputePerPixelHeightDisplacement(offset, lod, ppdParam POM_USER_DATA_ARGUMENTS);
 
 #endif
 

com.unity.shadergraph/CHANGELOG.md

@@ -32,6 +32,7 @@ The version number for this package has increased due to a version update of a r
 - Fixed an issue where user setting a property to not Exposed, Hybrid-Instanced would result in a non-Hybrid Global property [1285700]
 - Fixed an issue with Gradient when it is used as expose parameters. Generated code was failing [1285640 ]
 - Fixed the subgraph slot sorting function [1286805]
+- Fixed Parallax Occlusion Mapping not working in sub graphs. [1221317](https://issuetracker.unity3d.com/product/unity/issues/guid/1221317/)
 
 ## [10.1.0] - 2020-10-12
 

com.unity.shadergraph/Editor/Data/Nodes/UV/ParallaxOcclusionMappingNode.cs

@@ -111,19 +111,23 @@ public void GenerateNodeFunction(FunctionRegistry registry, GenerationMode gener
             registry.ProvideFunction(GetFunctionName(), s =>
                 {
                     s.AppendLine("// Required struct and function for the ParallaxOcclusionMapping function:");
-                    s.AppendLine($"$precision ComputePerPixelHeightDisplacement_{GetVariableNameForNode()}($precision2 texOffsetCurrent, $precision lod, PerPixelHeightDisplacementParam param)");
+                    s.AppendLine($"$precision ComputePerPixelHeightDisplacement_{GetVariableNameForNode()}($precision2 texOffsetCurrent, $precision lod, PerPixelHeightDisplacementParam param, TEXTURE2D_PARAM(heightTexture, heightSampler))");
                     using (s.BlockScope())
                     {
-                        s.AppendLine("return SAMPLE_TEXTURE2D_LOD({0}, {1}, param.uv + texOffsetCurrent, lod).r;",
-                            heightmap,
-                            edgesSampler.Any() ? GetSlotValue(kHeightmapSamplerSlotId, generationMode) : "sampler" + heightmap);
+                        s.AppendLine("return SAMPLE_TEXTURE2D_LOD(heightTexture, heightSampler, param.uv + texOffsetCurrent, lod).r;");
                     }
+                            // heightmap,
+                            // edgesSampler.Any() ? GetSlotValue(kHeightmapSamplerSlotId, generationMode) : "sampler" + heightmap);
 
                     s.AppendLine($"#define ComputePerPixelHeightDisplacement ComputePerPixelHeightDisplacement_{GetVariableNameForNode()}");
                     s.AppendLine($"#define POM_NAME_ID {GetVariableNameForNode()}");
+                    s.AppendLine($"#define POM_USER_DATA_PARAMETERS , TEXTURE2D_PARAM(heightTexture, samplerState)");
+                    s.AppendLine($"#define POM_USER_DATA_ARGUMENTS , TEXTURE2D_ARGS(heightTexture, samplerState)");
                     s.AppendLine(perPixelDisplacementInclude);
                     s.AppendLine($"#undef ComputePerPixelHeightDisplacement");
                     s.AppendLine($"#undef POM_NAME_ID");
+                    s.AppendLine($"#undef POM_USER_DATA_PARAMETERS");
+                    s.AppendLine($"#undef POM_USER_DATA_ARGUMENTS");
                 });
         }
 
@@ -134,6 +138,8 @@ public void GenerateNodeCode(ShaderStringBuilder sb, GenerationMode generationMo
             string uvs = GetSlotValue(kUVsSlotId, generationMode);
             string lod = GetSlotValue(kLodSlotId, generationMode);
             string lodThreshold = GetSlotValue(kLodThresholdSlotId, generationMode);
+            string heightmap = GetSlotValue(kHeightmapSlotId, generationMode);
+            string sampler = GetSlotValue(kHeightmapSamplerSlotId, generationMode);
 
             string tmpPOMParam = GetVariableNameForNode() + "_POM";
             string tmpViewDir = GetVariableNameForNode() + "_ViewDir";
@@ -155,7 +161,7 @@ public void GenerateNodeCode(ShaderStringBuilder sb, GenerationMode generationMo
 
             sb.AppendLines($@"
 $precision {tmpOutHeight};
-$precision2 {GetVariableNameForSlot(kParallaxUVsOutputSlotId)} = {uvs} + ParallaxOcclusionMapping{GetVariableNameForNode()}({lod}, {lodThreshold}, {steps}, {tmpViewDirUV}, {tmpPOMParam}, {tmpOutHeight});
+$precision2 {GetVariableNameForSlot(kParallaxUVsOutputSlotId)} = {uvs} + ParallaxOcclusionMapping{GetVariableNameForNode()}({lod}, {lodThreshold}, {steps}, {tmpViewDirUV}, {tmpPOMParam}, {tmpOutHeight}, TEXTURE2D_ARGS({heightmap}, {sampler}));
 
 $precision {GetVariableNameForSlot(kPixelDepthOffsetOutputSlotId)} = ({tmpMaxHeight} - {tmpOutHeight} * {tmpMaxHeight}) / max({tmpNdotV}, 0.0001);
 ");