Use current Defrag Count in Surface Cache

Author: urasmus

Packages/com.unity.render-pipelines.core/Runtime/Lighting/SurfaceCache/SurfaceCache.cs

@@ -194,11 +194,11 @@ internal class SurfaceCacheResourceSet
         internal int TemporalFilteringKernel;
         internal uint3 TemporalFilteringKernelGroupSize;
 
-        internal readonly uint SubGroupSize;
+        internal readonly uint ComputeSubGroupSize;
 
-        internal SurfaceCacheResourceSet(uint subGroupSize)
+        internal SurfaceCacheResourceSet(uint computeSubGroupSize)
         {
-            SubGroupSize = subGroupSize;
+            ComputeSubGroupSize = computeSubGroupSize;
         }
 
         internal bool LoadFromRenderPipelineResources(RayTracingContext rtContext)
@@ -223,9 +223,9 @@ internal bool LoadFromRenderPipelineResources(RayTracingContext rtContext)
             TemporalFilteringKernel = TemporalFilteringShader.FindKernel("FilterTemporally");
             TemporalFilteringShader.GetKernelThreadGroupSizes(TemporalFilteringKernel, out TemporalFilteringKernelGroupSize.x, out TemporalFilteringKernelGroupSize.y, out TemporalFilteringKernelGroupSize.z);
 
-            Debug.Assert(SubGroupSize == 8 || SubGroupSize == 16 || SubGroupSize == 32 || SubGroupSize == 48 || SubGroupSize == 64);
+            Debug.Assert(ComputeSubGroupSize == 8 || ComputeSubGroupSize == 16 || ComputeSubGroupSize == 32 || ComputeSubGroupSize == 48 || ComputeSubGroupSize == 64);
             DefragShader = rpResources.defragShader;
-            var defragKeyword = "SUB_GROUP_SIZE_" + SubGroupSize;
+            var defragKeyword = "SUB_GROUP_SIZE_" + ComputeSubGroupSize;
             DefragShader.EnableKeyword(defragKeyword);
             DefragKernel = DefragShader.FindKernel("Defrag");
             DefragShader.GetKernelThreadGroupSizes(DefragKernel, out DefragKernelGroupSize.x, out DefragKernelGroupSize.y, out DefragKernelGroupSize.z);
@@ -256,6 +256,7 @@ internal bool LoadFromRenderPipelineResources(RayTracingContext rtContext)
     internal class SurfaceCache : IDisposable
     {
         public const uint CascadeMax = 8;
+
         private readonly GraphicsBuffer _punctualLightSamples;
         private readonly SurfaceCachePatchList _patches;
         private readonly SurfaceCacheVolume _volume;
@@ -267,7 +268,8 @@ internal class SurfaceCache : IDisposable
         private SurfaceCachePatchFilteringParameterSet _patchFilteringParams;
 
         private float _shortHysteresis;
-        readonly private uint _defragCount;
+        private uint _defragCount = 1;
+        private uint _defragOffset = 0;
         readonly private float _albedoBoost = 1.0f;
 
         public GraphicsBuffer PunctualLightSamples => _punctualLightSamples;
@@ -323,7 +325,7 @@ private class DefragPassData
             internal GraphicsBuffer PatchStatistics;
             internal GraphicsBuffer CellPatchIndices;
             internal uint RingConfigStartFlipflop;
-            internal uint EvenIterationPatchOffset;
+            internal uint ComputeSubGroupSize;
             internal uint OddIterationPatchOffset;
         }
 
@@ -442,7 +444,6 @@ internal static class ShaderIDs
 
         public SurfaceCache(
             SurfaceCacheResourceSet resources,
-            uint defragCount,
             SurfaceCacheVolumeParameterSet volParams)
         {
             Debug.Assert(volParams.CascadeCount != 0);
@@ -457,23 +458,26 @@ public SurfaceCache(
             _ringConfig = new SurfaceCacheRingConfig();
             _patches = new SurfaceCachePatchList(patchCapacity);
             _punctualLightSamples = new GraphicsBuffer(GraphicsBuffer.Target.Structured, (int)punctualLightSampleCount, sizeof(float) * 17);
-
-            _defragCount = defragCount;
         }
 
         public void SetEstimationParams(SurfaceCacheEstimationParameterSet estimationParams)
         {
             _estimationParams = estimationParams;
         }
 
+        public void SetDefragCount(uint count)
+        {
+            _defragCount = count;
+        }
+
         public void SetPatchFilteringParams(SurfaceCachePatchFilteringParameterSet patchFilteringParams)
         {
             Debug.Assert(0.0f <= patchFilteringParams.TemporalSmoothing && patchFilteringParams.TemporalSmoothing <= 1.0f);
             _patchFilteringParams = patchFilteringParams;
             _shortHysteresis = Mathf.Lerp(0.75f, 0.95f, patchFilteringParams.TemporalSmoothing);
         }
 
-        public void UpdateVolumeSize(float size)
+        public void SetVolumeSize(float size)
         {
             _volume.VoxelMinSize = size / (_volume.SpatialResolution * (float)(1u << (int)(_volume.CascadeCount - 1u)));
         }
@@ -495,7 +499,7 @@ private void RecordDefragmentation(RenderGraph renderGraph, uint frameIdx)
         {
             using (var builder = renderGraph.AddComputePass("Surface Cache Defrag", out DefragPassData passData))
             {
-                passData.IterationOffset = frameIdx * _defragCount;
+                passData.IterationOffset = _defragOffset;
                 passData.IterationCount = _defragCount;
                 passData.Shader = _resources.DefragShader;
                 passData.Keyword = _resources.DefragKeyword;
@@ -510,15 +514,16 @@ private void RecordDefragmentation(RenderGraph renderGraph, uint frameIdx)
                 passData.PatchGeometries = Patches.Geometries;
                 passData.PatchStatistics = Patches.Statistics;
                 passData.CellPatchIndices = Volume.CellPatchIndices;
-                passData.EvenIterationPatchOffset = 0;
-                passData.OddIterationPatchOffset = _resources.SubGroupSize / 2;
+                passData.ComputeSubGroupSize = _resources.ComputeSubGroupSize;
 
                 builder.AllowGlobalStateModification(true); // Set to ensure ordering.
                 builder.SetRenderFunc((DefragPassData data, ComputeGraphContext cgContext) => Defrag(data, cgContext));
 
                 if (_defragCount % 2 == 1)
                     RingConfig.Flip();
             }
+
+            _defragOffset += _defragCount;
         }
 
         private void RecordEviction(RenderGraph renderGraph, uint frameIdx)
@@ -770,7 +775,7 @@ static void Defrag(DefragPassData data, ComputeGraphContext cgContext)
             {
                 uint readOffset = SurfaceCacheRingConfig.GetOffsetA(flipflop);
                 uint writeOffset = SurfaceCacheRingConfig.GetOffsetB(flipflop);
-                uint patchOffset = iterationIndex % 2 == 0 ? data.EvenIterationPatchOffset : data.OddIterationPatchOffset;
+                uint patchOffset = iterationIndex % 2 * (data.ComputeSubGroupSize / 2);
 
                 cmd.SetComputeIntParam(shader, ShaderIDs._RingConfigReadOffset, (int)readOffset);
                 cmd.SetComputeIntParam(shader, ShaderIDs._RingConfigWriteOffset, (int)writeOffset);

Packages/com.unity.render-pipelines.universal/Runtime/RendererFeatures/SurfaceCacheGIRendererFeature/SurfaceCacheGIRendererFeature.cs

@@ -356,7 +356,6 @@ private class ScreenIrradianceUpsamplingPassData
 
             // Stored for runtime cache recreation when resolution or cascade count changes
             private readonly Rendering.SurfaceCacheResourceSet _coreResources;
-            private uint _defragCount;
 
             public SurfaceCachePass(
                 RayTracingContext rtContext,
@@ -371,7 +370,6 @@ public SurfaceCachePass(
                 bool debugEnabled,
                 DebugViewMode_ debugViewMode,
                 bool debugShowSamplePosition,
-                uint defragCount,
                 SurfaceCacheVolumeParameterSet volParams)
             {
                 Debug.Assert(volParams.CascadeCount != 0);
@@ -403,9 +401,8 @@ public SurfaceCachePass(
                 _debugShowSamplePosition = debugShowSamplePosition;
 
                 _coreResources = resourceSet;
-                _defragCount = defragCount;
 
-                _cache = new SurfaceCache(resourceSet, defragCount, volParams);
+                _cache = new SurfaceCache(resourceSet, volParams);
                 _sceneTracker = new SceneUpdatesTracker();
 
                 _world = new SurfaceCacheWorld();
@@ -521,7 +518,6 @@ public override void RecordRenderGraph(RenderGraph renderGraph, ContextContainer
                 var stack = VolumeManager.instance.stack;
                 var volume = stack.GetComponent<SurfaceCacheGIVolumeOverride>();
                 var volumeParams = GetVolumeParametersOrDefaults(volume);
-                _defragCount = volumeParams.DefragCount;
 
                 // Detect structural changes that require buffer reallocation.
                 if (volumeParams.VolumeResolution != _cache.Volume.SpatialResolution || volumeParams.VolumeCascadeCount != _cache.Volume.CascadeCount)
@@ -537,13 +533,14 @@ public override void RecordRenderGraph(RenderGraph renderGraph, ContextContainer
                         Size = volumeParams.VolumeSize,
                         CascadeCount = newCascadeCount
                     };
-                    _cache = new SurfaceCache(_coreResources, _defragCount, newVolParams);
+                    _cache = new SurfaceCache(_coreResources, newVolParams);
                     _frameIdx = 0;
                 }
 
                 _cache.SetEstimationParams(volumeParams.EstimationParams);
                 _cache.SetPatchFilteringParams(volumeParams.PatchFilteringParams);
-                _cache.UpdateVolumeSize(volumeParams.VolumeSize);
+                _cache.SetVolumeSize(volumeParams.VolumeSize);
+                _cache.SetDefragCount(volumeParams.DefragCount);
 
                 bool useMotionVectorPatchSeeding = UseMotionVectorPatchSeeding(cameraData.cameraType);
 
@@ -1037,7 +1034,6 @@ public override void Create()
                 _parameterSet.DebugEnabled,
                 _parameterSet.DebugViewMode,
                 _parameterSet.DebugShowSamplePosition,
-                defragCount: DEFAULT_DEFRAG_COUNT,
                 volParams);
 
             _pass.renderPassEvent = RenderPassEvent.AfterRenderingPrePasses + 1;