Fix meta for terrains in HDRP

https://jira.unity3d.com/browse/UUM-71171

The meta pass of the default HDRP terrain shader (TerrainLit.shader) is currently broken. It always outputs black albedo, resulting in no bounced lighting whatsoever. This was a regression introduced in this PR https://github.cds.internal.unity3d.com/unity/unity/pull/20840, which moved around some shader includes, but neglected to update the Terrain shader according. The bug is essentially that the meta pass is incorrectly using camera-relative rendering. This fix is to restore the missing include in the terrain shader.

Author: pema99

Packages/com.unity.render-pipelines.high-definition/Runtime/Material/TerrainLit/TerrainLitTemplate.hlsl

@@ -27,6 +27,10 @@
 #endif
 #ifdef SCENESELECTIONPASS
     #include "Packages/com.unity.render-pipelines.high-definition/Runtime/ShaderLibrary/PickingSpaceTransforms.hlsl"
+#elif SHADERPASS == SHADERPASS_LIGHT_TRANSPORT
+    // Use Unity's built-in matrices for meta pass rendering
+    #define SCENEPICKINGPASS
+    #include "Packages/com.unity.render-pipelines.high-definition/Runtime/ShaderLibrary/PickingSpaceTransforms.hlsl"
 #endif
 #include "Packages/com.unity.render-pipelines.high-definition/Runtime/Material/Material.hlsl"
 

Tests/SRPTests/Projects/HDRP_Tests/Assets/Tests/LightBaker/InputExtractionMaterials.cs

@@ -19,13 +19,12 @@ public class MetaPassSceneTest
         public string ObjectName { get; set; } // Object for which to test the metaPass data
         public MetaPassType MetaPassType { get; set; } = MetaPassType.Albedo;
         public int TextureCount { get; set; }
+        public float RMSEThreshold { get; set; } = 0.0001f;
         public override string ToString() { return $"{SceneName}-{ObjectName}-{MetaPassType}"; }
     };
 
     internal class InputExtractionMaterials
     {
-        private static readonly float metaPassRMSETolerance = 0.0001f;
-
         Texture2D ConvertVector4ImageToRGBAHalfTexture(uint width, uint height, Vector4[] textureData)
         {
             Texture2D texture = new((int)width, (int)height, TextureFormat.RGBAHalf, false);
@@ -53,8 +52,8 @@ Texture2D ConvertVector4ImageToRGBAHalfTexture(uint width, uint height, Vector4[
             new() { SceneName = "Metapass_BasicMaterials", ObjectName = "albedoTexTiling23", MetaPassType = MetaPassType.Albedo , TextureCount = 13 },
             new() { SceneName = "Metapass_BasicMaterials", ObjectName = "emissiveTexOffset_p5p3", MetaPassType = MetaPassType.Emission , TextureCount = 13 },
             new() { SceneName = "Metapass_BasicMaterials", ObjectName = "albedoTexOffset_p5p3", MetaPassType = MetaPassType.Albedo , TextureCount = 13 },
-            new() { SceneName = "BakedLightingTerrainAlbedo-editor", ObjectName = "Terrain", MetaPassType = MetaPassType.Albedo , TextureCount = 3 },
-            new() { SceneName = "BakedLightingTerrainAlbedo-editor", ObjectName = "TerrainOffset", MetaPassType = MetaPassType.Albedo , TextureCount = 3 }
+            new() { SceneName = "BakedLightingTerrainAlbedo-editor", ObjectName = "Terrain", MetaPassType = MetaPassType.Albedo , TextureCount = 3, RMSEThreshold = 0.03f },
+            new() { SceneName = "BakedLightingTerrainAlbedo-editor", ObjectName = "TerrainOffset", MetaPassType = MetaPassType.Albedo , TextureCount = 3, RMSEThreshold = 0.03f }
         };
 
         [Test, Category("Graphics")]
@@ -108,7 +107,7 @@ public void MetaPassTemplateTests([ValueSource(nameof(metaPassTests))]MetaPassSc
                 ActivePixelTests = ImageComparisonSettings.PixelTests.None,
                 ActiveImageTests = ImageComparisonSettings.ImageTests.RMSE,
                 IncorrectPixelsThreshold = 1.0f / (actualTexture2D.width * actualTexture2D.height),
-                RMSEThreshold = metaPassRMSETolerance
+                RMSEThreshold = metaPassTest.RMSEThreshold,
             };
 
             try

Tests/SRPTests/Projects/HDRP_Tests/Assets/Tests/LightBaker/Scenes/BakedLightingTerrainAlbedo-editor.unity

@@ -191,7 +191,7 @@ Terrain:
   m_PreserveTreePrototypeLayers: 0
   m_DeringLightProbesForTrees: 1
   m_ReceiveGI: 1
-  m_ScaleInLightmap: 0.0512
+  m_ScaleInLightmap: 1
   m_LightmapParameters: {fileID: 15203, guid: 0000000000000000f000000000000000, type: 0}
   m_GroupingID: 0
   m_RenderingLayerMask: 1
@@ -556,8 +556,12 @@ Light:
   m_BoundingSphereOverride: {x: 0, y: 0, z: 0, w: 0}
   m_UseBoundingSphereOverride: 0
   m_UseViewFrustumForShadowCasterCull: 1
+  m_ForceVisible: 0
   m_ShadowRadius: 0
   m_ShadowAngle: 0
+  m_LightUnit: 1
+  m_LuxAtDistance: 1
+  m_EnableSpotReflector: 1
 --- !u!114 &700898409
 MonoBehaviour:
   m_ObjectHideFlags: 0
@@ -788,7 +792,7 @@ Terrain:
   m_PreserveTreePrototypeLayers: 0
   m_DeringLightProbesForTrees: 1
   m_ReceiveGI: 1
-  m_ScaleInLightmap: 0.0512
+  m_ScaleInLightmap: 1
   m_LightmapParameters: {fileID: 15203, guid: 0000000000000000f000000000000000, type: 0}
   m_GroupingID: 0
   m_RenderingLayerMask: 1
@@ -864,6 +868,7 @@ MeshRenderer:
   m_RayTraceProcedural: 0
   m_RayTracingAccelStructBuildFlagsOverride: 0
   m_RayTracingAccelStructBuildFlags: 1
+  m_SmallMeshCulling: 1
   m_RenderingLayerMask: 1
   m_RendererPriority: 0
   m_Materials:
@@ -1174,6 +1179,7 @@ MeshRenderer:
   m_RayTraceProcedural: 0
   m_RayTracingAccelStructBuildFlagsOverride: 0
   m_RayTracingAccelStructBuildFlags: 1
+  m_SmallMeshCulling: 1
   m_RenderingLayerMask: 1
   m_RendererPriority: 0
   m_Materials:
@@ -1321,8 +1327,12 @@ Light:
   m_BoundingSphereOverride: {x: 0, y: 0, z: 0, w: 0}
   m_UseBoundingSphereOverride: 0
   m_UseViewFrustumForShadowCasterCull: 1
+  m_ForceVisible: 0
   m_ShadowRadius: 0
   m_ShadowAngle: 0
+  m_LightUnit: 1
+  m_LuxAtDistance: 1
+  m_EnableSpotReflector: 1
 --- !u!114 &1665680526
 MonoBehaviour:
   m_ObjectHideFlags: 0