[HDRP][Water] Various fixes and samples improvements

Several improvements to water samples:
- Reorg of gameobjects into prefabs for clarity
- Added link to Global Settings from the helper window
- Small rework of meshes and textures to reduce sample size

Improved test coverage:
- Test water mask
- Test water decals
- Test cpu readback

Improved system usability and workflows
Various fixes, mostly minor bugs see release notes

Author: adrien-de-tocqueville

Packages/com.unity.render-pipelines.core/Runtime/Textures/Texture2DAtlas.cs

@@ -638,6 +638,32 @@ public virtual bool NeedsUpdate(Texture texture, bool needMips = false)
             return false;
         }
 
+        /// <summary>
+        /// Check if a slot needs to be updated in the atlas.
+        /// </summary>
+        /// <param name="id">The id.</param>
+        /// <param name="updateCount">The update count.</param>
+        /// <param name="needMips">Texture uses mips.</param>
+        /// <returns>True if slot needs update, false otherwise.</returns>
+        public virtual bool NeedsUpdate(int id, int updateCount, bool needMips = false)
+        {
+            int atlasUpdateCount;
+            if (m_IsGPUTextureUpToDate.TryGetValue(id, out atlasUpdateCount))
+            {
+                if (updateCount != atlasUpdateCount)
+                {
+                    m_IsGPUTextureUpToDate[id] = updateCount;
+                    return true;
+                }
+            }
+            else
+            {
+                m_IsGPUTextureUpToDate[id] = updateCount;
+            }
+
+            return false;
+        }
+
         /// <summary>
         /// Check if contents of a texture needs to be updated in the atlas.
         /// </summary>

Packages/com.unity.render-pipelines.core/Samples~/Common/Scripts/Editor/SamplesShowcaseEditor.cs

@@ -10,6 +10,7 @@
 using System.Collections;
 using System.Reflection;
 using UnityEngine.Rendering;
+using UnityEditor.Inspector.GraphicsSettingsInspectors;
 
 [InitializeOnLoad]
 [CustomEditor(typeof(SamplesShowcase))]
@@ -174,6 +175,11 @@ public override VisualElement CreateInspectorGUI()
                     {
                         RequiredSettingBase.showSettingCallback(setting);
                     }
+                    else if (!string.IsNullOrEmpty(setting.globalSettingsType))
+					{
+                        var type = Type.GetType(setting.globalSettingsType);
+                        GraphicsSettingsInspectorUtility.OpenAndScrollTo(type);
+					}
                     else
                     {
                         SettingsService.OpenProjectSettings(setting.projectSettingsPath);

Packages/com.unity.render-pipelines.core/Samples~/Common/Scripts/RequiredSettings/RequiredSettingBase.cs

@@ -6,6 +6,7 @@
 using UnityEditor;
 using UnityEngine;
 using UnityEngine.Rendering;
+using System.Reflection;
 
 namespace UnityEngine.Rendering
 {
@@ -21,6 +22,8 @@ public class RequiredSettingBase : IRequiredSetting
         public string name => m_name;
         public string description => m_description;
 
+        public string globalSettingsType;
+
         public ValueType valueType = ValueType.Bool;
         public float targetValue = 1f;
         public ValidationType validationType = ValidationType.Equal;
@@ -71,6 +74,15 @@ public virtual bool state
         {
             get
             {
+                if (!string.IsNullOrEmpty(globalSettingsType))
+				{
+                    var type = Type.GetType(globalSettingsType);
+                    var field = type.GetField(propertyPath, BindingFlags.NonPublic | BindingFlags.Instance);
+                    var getSettings = typeof(GraphicsSettings).GetMethod("GetRenderPipelineSettings").MakeGenericMethod(type);
+                    object settings = getSettings.Invoke(null, null);
+                    return (bool)field.GetValue(settings);
+				}
+
                 if (property == null)
                     return false;
 

Packages/com.unity.render-pipelines.high-definition/Editor/AssetProcessors/ShaderGraphMaterialsUpdater.cs

@@ -19,6 +19,11 @@ static ShaderGraphMaterialsUpdater()
 
         static void OnShaderGraphSaved(Shader shader, object saveContext)
         {
+            #if UNITY_EDITOR
+            // Water decals don't have an HDSaveContext, but this call has no effect if the shader is not a WaterDecal
+            HDRenderPipeline.currentPipeline?.waterSystem?.UpdateWaterDecalAtlas(shader);
+            #endif
+
             // In case the shader is not HDRP
             if (!(saveContext is HDSaveContext hdSaveContext))
                 return;

Packages/com.unity.render-pipelines.high-definition/Editor/BuildProcessors/HDRPBuildData.cs

@@ -16,6 +16,7 @@ internal class HDRPBuildData : IDisposable
         public List<HDRenderPipelineAsset> renderPipelineAssets { get; private set; } = new List<HDRenderPipelineAsset>();
         public bool playerNeedRaytracing { get; private set; }
         public bool stripDebugVariants { get; private set; } = true;
+        public bool waterDecalMaskAndCurrent { get; private set; }
         public Dictionary<int, ComputeShader> rayTracingComputeShaderCache { get; private set; } = new();
         public Dictionary<int, ComputeShader> computeShaderCache { get; private set; } = new();
 
@@ -59,6 +60,10 @@ public HDRPBuildData(BuildTarget buildTarget, bool isDevelopmentBuild)
 
                     stripDebugVariants = !isDevelopmentBuild || GraphicsSettings.GetRenderPipelineSettings<ShaderStrippingSetting>().stripRuntimeDebugShaders;
                 }
+
+                var waterSettings = GraphicsSettings.GetRenderPipelineSettings<WaterSystemGlobalSettings>();
+                if (waterSettings != null)
+                    waterDecalMaskAndCurrent = waterSettings.waterDecalMaskAndCurrent;
             }
 
             m_Instance = this;
@@ -71,6 +76,7 @@ public void Dispose()
             computeShaderCache?.Clear();
             playerNeedRaytracing = false;
             stripDebugVariants = true;
+            waterDecalMaskAndCurrent = false;
             buildingPlayerForHDRenderPipeline = false;
             runtimeShaders = null;
             materialResources = null;

Packages/com.unity.render-pipelines.high-definition/Editor/BuildProcessors/HDRPPreprocessShaders.cs

@@ -42,6 +42,16 @@ protected override bool DoShadersStripper(HDRenderPipelineAsset hdrpAsset, Shade
                 if (stripDebugVariants && snippet.passName.StartsWith(WaterSystem.k_WaterMaskPass))
                     return true;
             }
+            if (HDRPBuildData.instance.waterDecalMaskAndCurrent)
+            {
+                if (inputData.shaderKeywordSet.IsEnabled(m_WaterDecalPartial))
+                    return true;
+            }
+            else
+            {
+                if (inputData.shaderKeywordSet.IsEnabled(m_WaterDecalComplete))
+                    return true;
+            }
 
             // If Screen Space Lens Flare is disabled, strip all the shaders
             if (!settings.supportScreenSpaceLensFlare)

Packages/com.unity.render-pipelines.high-definition/Editor/Material/BaseShaderPreprocessor.cs

@@ -88,6 +88,8 @@ abstract class BaseShaderPreprocessor
         protected ShaderKeyword m_DecalSurfaceGradient;
         protected ShaderKeyword m_EditorVisualization;
         protected ShaderKeyword m_SupportWater;
+        protected ShaderKeyword m_WaterDecalPartial;
+        protected ShaderKeyword m_WaterDecalComplete;
         protected ShaderKeyword m_SupportWaterCaustics;
         protected ShaderKeyword m_SupportWaterCausticsShadow;
         protected ShaderKeyword m_SupportWaterAbsorption;
@@ -133,6 +135,8 @@ public BaseShaderPreprocessor()
             m_DecalSurfaceGradient = new ShaderKeyword("DECAL_SURFACE_GRADIENT");
             m_EditorVisualization = new ShaderKeyword("EDITOR_VISUALIZATION");
             m_SupportWater = new ShaderKeyword("SUPPORT_WATER");
+            m_WaterDecalPartial = new ShaderKeyword("WATER_DECAL_PARTIAL");
+            m_WaterDecalComplete = new ShaderKeyword("WATER_DECAL_COMPLETE");
             m_SupportWaterCaustics = new ShaderKeyword("SUPPORT_WATER_CAUSTICS");
             m_SupportWaterCausticsShadow = new ShaderKeyword("SUPPORT_WATER_CAUSTICS_SHADOW");
             m_SupportWaterAbsorption = new ShaderKeyword("SUPPORT_WATER_ABSORPTION");

Packages/com.unity.render-pipelines.high-definition/Editor/Material/Water/ShaderGraph/Node/UnpackData_Water.cs

@@ -45,10 +45,18 @@ public sealed override void UpdateNodeAfterDeserialization()
 
         public void GenerateNodeCode(ShaderStringBuilder sb, GenerationMode generationMode)
         {
-            sb.AppendLine("$precision {1} = saturate(IN.{0}.x); $precision {2} = IN.{0}.y;",
-                ShaderGeneratorNames.GetUVName(UVChannel.UV1),
+            // See PackWaterVertexData
+
+            // Low Frequency Height
+            sb.AppendLine("$precision {0} = saturate(IN.{1}.w);",
                 GetVariableNameForSlot(kLowFrequencyHeightOutputSlotId),
-                GetVariableNameForSlot(kHorizontalDisplacementOutputSlotId)
+                ShaderGeneratorNames.GetUVName(UVChannel.UV1)
+            );
+
+            // Horizontal Displacement
+            sb.AppendLine("$precision {0} = IN.{1}.w;",
+                GetVariableNameForSlot(kHorizontalDisplacementOutputSlotId),
+                ShaderGeneratorNames.GetUVName(UVChannel.UV0)
             );
         }
 

Packages/com.unity.render-pipelines.high-definition/Editor/Material/Water/ShaderGraph/Tessellation.template.hlsl

@@ -12,7 +12,6 @@ VaryingsMeshToDS InterpolateWithBaryCoordsMeshToDS(VaryingsMeshToDS input0, Vary
     TESSELLATION_INTERPOLATE_BARY(normalWS, baryCoords);
     TESSELLATION_INTERPOLATE_BARY(texCoord0, baryCoords);
     TESSELLATION_INTERPOLATE_BARY(texCoord1, baryCoords);
-    output.positionPredisplacementRWS = output.positionRWS;
 
     // Pass-Through for custom interpolator
     $splice(CustomInterpolatorInterpolateWithBaryCoordsMeshToDS)
@@ -42,8 +41,7 @@ VertexDescriptionInputs VaryingsMeshToDSToVertexDescriptionInputs(VaryingsMeshTo
 // y - 2->0 edge
 // z - 0->1 edge
 // w - inside tessellation factor
-// The water shader graph required these four fields to be fed (not an option)
-VaryingsMeshToDS ApplyTessellationModification(VaryingsMeshToDS input, float3 timeParameters)
+void ApplyTessellationModification(VaryingsMeshToDS input, float3 timeParameters, inout VaryingsMeshToPS output, out VertexDescription vertexDescription)
 {
     // HACK: As there is no specific tessellation stage for now in shadergraph, we reuse the vertex description mechanism.
     // It mean we store TessellationFactor inside vertex description causing extra read on both vertex and hull stage, but unused parameters are optimize out by the shader compiler, so no impact.
@@ -53,28 +51,14 @@ VaryingsMeshToDS ApplyTessellationModification(VaryingsMeshToDS input, float3 ti
     $VertexDescriptionInputs.TimeParameters: vertexDescriptionInputs.TimeParameters = timeParameters;
 
     // evaluate vertex graph
-    VertexDescription vertexDescription = VertexDescriptionFunction(vertexDescriptionInputs);
+    vertexDescription = VertexDescriptionFunction(vertexDescriptionInputs);
 
     // Backward compatibility with old graphs
     $VertexDescriptionInputs.uv0: vertexDescription.Displacement = vertexDescription.uv0.xyz;
     $VertexDescriptionInputs.uv1: vertexDescription.LowFrequencyHeight = vertexDescription.uv1.x;
 
-    // Export for the following stage
-    input.positionRWS = TransformObjectToWorld(vertexDescription.Position + vertexDescription.Displacement);
-    input.normalWS = vertexDescription.Normal;
-    PackWaterVertexData(vertexDescription, input.texCoord0, input.texCoord1);
-
-    return input;
-}
-
-#ifdef USE_CUSTOMINTERP_SUBSTRUCT
-
-// This will evaluate the custom interpolator and update the varying structure
-void VertMeshTesselationCustomInterpolation(VaryingsMeshToDS input, inout VaryingsMeshToPS output)
-{
+    // Custom interpolators
     $splice(CustomInterpolatorVertMeshTesselationCustomInterpolation)
 }
 
-#endif // USE_CUSTOMINTERP_SUBSTRUCT
-
 #endif // TESSELLATION_ON

Packages/com.unity.render-pipelines.high-definition/Editor/Material/Water/ShaderGraph/Vertex.template.hlsl

@@ -19,30 +19,30 @@ VertexDescriptionInputs AttributesMeshToVertexDescriptionInputs(AttributesMesh i
     return output;
 }
 
-void PackWaterVertexData(VertexDescription vertexDescription, out float4 uv0, out float4 uv1)
+void PackWaterVertexData(VertexDescription vertex, out float4 uv0, out float4 uv1)
 {
-    float3 displacement = vertexDescription.Displacement;
-
-    #if defined(SHADER_STAGE_VERTEX) && defined(TESSELLATION_ON)
-    uv0 = float4(vertexDescription.Displacement, 1.0);
-    uv1 = float4(vertexDescription.Position, 1.0);
-    #else
-    uv0 = float4(vertexDescription.Position.x, vertexDescription.Position.z, displacement.y, 0.0);
-    uv1 = float4(vertexDescription.LowFrequencyHeight, length(float2(displacement.x, displacement.z)), 0.0, 0.0);
-    #endif
+#if defined(SHADER_STAGE_VERTEX) && defined(TESSELLATION_ON)
+    uv0 = float4(vertex.Displacement, 1.0);
+    uv1 = float4(vertex.Position, 1.0);
+#else
+    uv0.xy = vertex.Position.xz;
+    uv0.z = vertex.Displacement.y;
+    uv0.w = length(vertex.Displacement.xz);
+
+    if (_GridSize.x >= 0)
+        uv1.xyz = TransformObjectToWorld(vertex.Position + vertex.Displacement);
+    uv1.w = vertex.LowFrequencyHeight;
+#endif
 }
 
-// The water shader graph required these four fields to be fed (not an option)
+#if defined(TESSELLATION_ON)
+    #define VaryingsMeshType VaryingsMeshToDS
+#else
+    #define VaryingsMeshType VaryingsMeshToPS
+#endif
+
 // Modifications should probably be replicated to ApplyTessellationModification
-AttributesMesh ApplyMeshModification(AttributesMesh input, float3 timeParameters
-    #ifdef USE_CUSTOMINTERP_SUBSTRUCT
-    #ifdef TESSELLATION_ON
-    , inout VaryingsMeshToDS varyings
-    #else
-    , inout VaryingsMeshToPS varyings
-    #endif
-    #endif
-    )
+void ApplyMeshModification(AttributesMesh input, float3 timeParameters, inout VaryingsMeshType varyings, out VertexDescription vertexDescription)
 {
     // build graph inputs
     VertexDescriptionInputs vertexDescriptionInputs = AttributesMeshToVertexDescriptionInputs(input);
@@ -51,21 +51,18 @@ AttributesMesh ApplyMeshModification(AttributesMesh input, float3 timeParameters
     $VertexDescriptionInputs.TimeParameters: vertexDescriptionInputs.TimeParameters = timeParameters;
 
     // evaluate vertex graph
-    VertexDescription vertexDescription = VertexDescriptionFunction(vertexDescriptionInputs);
+    vertexDescription = VertexDescriptionFunction(vertexDescriptionInputs);
 
     // Backward compatibility with old graphs
     $VertexDescriptionInputs.uv0: vertexDescription.Displacement = vertexDescription.uv0.xyz;
     $VertexDescriptionInputs.uv1: vertexDescription.LowFrequencyHeight = vertexDescription.uv1.x;
 
-    input.positionOS = vertexDescription.Position + vertexDescription.Displacement;
-    input.normalOS = vertexDescription.Normal;
-    PackWaterVertexData(vertexDescription, input.uv0, input.uv1);
-
+    // Custom interpolators
     $splice(CustomInterpolatorVertMeshCustomInterpolation)
-
-    return input;
 }
 
+#undef VaryingsMeshType
+
 FragInputs BuildFragInputs(VaryingsMeshToPS input)
 {
     FragInputs output;
@@ -77,7 +74,7 @@ FragInputs BuildFragInputs(VaryingsMeshToPS input)
     output.tangentToWorld = k_identity3x3;
     output.positionSS = input.positionCS;       // input.positionCS is SV_Position
 
-    $FragInputs.positionRWS:                    output.positionRWS =                input.positionRWS;
+    $FragInputs.positionRWS:                    output.positionRWS =                input.texCoord1.xyz;
     $FragInputs.positionPixel:                  output.positionPixel =              input.positionCS.xy; // NOTE: this is not actually in clip space, it is the VPOS pixel coordinate value
     $FragInputs.positionPredisplacementRWS:     output.positionPredisplacementRWS = input.positionPredisplacementRWS;
     $FragInputs.tangentToWorld:                 output.tangentToWorld =             GetLocalFrame(input.normalWS);