Supporting SSGI in the render graph mode.

com.unity.render-pipelines.high-definition/CHANGELOG.md

@@ -189,6 +189,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
 - Added marker for all AOV request operation on GPU
 - Added remapping options for Depth Pyramid debug view mode
 - Added an option to support AOV shader at runtime in HDRP settings (case 1265070)
+- Supporting SSGI in the render graph mode.
 
 ### Fixed
 - Fix when rescale probe all direction below zero (1219246)

com.unity.render-pipelines.high-definition/Runtime/Lighting/ScreenSpaceLighting/ScreenSpaceGlobalIllumination.RenderGraph.cs

@@ -0,0 +1,114 @@
+using UnityEngine.Experimental.Rendering;
+using UnityEngine.Experimental.Rendering.RenderGraphModule;
+
+namespace UnityEngine.Rendering.HighDefinition
+{
+    public partial class HDRenderPipeline
+    {
+        class TraceSSGIPassData
+        {
+            public SSGITraceParameters parameters;
+            public TextureHandle depthTexture;
+            public TextureHandle normalBuffer;
+            public TextureHandle motionVectorsBuffer;
+            public TextureHandle colorPyramid;
+            public TextureHandle historyDepth;
+            public TextureHandle hitPointBuffer;
+            public TextureHandle outputBuffer;
+        }
+
+        TextureHandle TraceSSGI(RenderGraph renderGraph, HDCamera hdCamera, GlobalIllumination giSettings, TextureHandle depthPyramid, TextureHandle normalBuffer, TextureHandle motionVectorsBuffer)
+        {
+            using (var builder = renderGraph.AddRenderPass<TraceSSGIPassData>("Trace SSGI", out var passData, ProfilingSampler.Get(HDProfileId.SSGITrace)))
+            {
+                builder.EnableAsyncCompute(false);
+
+                passData.parameters = PrepareSSGITraceParameters(hdCamera, giSettings);
+                passData.depthTexture = builder.ReadTexture(depthPyramid);
+                passData.normalBuffer = builder.ReadTexture(normalBuffer);
+                passData.motionVectorsBuffer = builder.ReadTexture(motionVectorsBuffer);
+                var colorPyramid = hdCamera.GetPreviousFrameRT((int)HDCameraFrameHistoryType.ColorBufferMipChain);
+                passData.colorPyramid = colorPyramid != null ? builder.ReadTexture(renderGraph.ImportTexture(colorPyramid)) : renderGraph.defaultResources.blackTextureXR;
+                var historyDepth = hdCamera.GetCurrentFrameRT((int)HDCameraFrameHistoryType.Depth);
+                passData.historyDepth = historyDepth != null ? builder.ReadTexture(renderGraph.ImportTexture(historyDepth)) : renderGraph.defaultResources.blackTextureXR;
+                passData.hitPointBuffer = builder.CreateTransientTexture(new TextureDesc(Vector2.one, true, true)
+                { colorFormat = GraphicsFormat.R16G16B16A16_SFloat, enableRandomWrite = true, name = "SSGI Hit Point"});
+                passData.outputBuffer = builder.WriteTexture(renderGraph.CreateTexture(new TextureDesc(Vector2.one, true, true)
+                { colorFormat = GraphicsFormat.R16G16B16A16_SFloat, enableRandomWrite = true, name = "SSGI Signal"}));
+
+                builder.SetRenderFunc(
+                (TraceSSGIPassData data, RenderGraphContext ctx) =>
+                {
+                    // We need to fill the structure that holds the various resources
+                    SSGITraceResources resources = new SSGITraceResources();
+                    resources.depthTexture = data.depthTexture;
+                    resources.normalBuffer = data.normalBuffer;
+                    resources.motionVectorsBuffer = data.motionVectorsBuffer;
+                    resources.colorPyramid = data.colorPyramid;
+                    resources.historyDepth = data.historyDepth;
+                    resources.hitPointBuffer = data.hitPointBuffer;
+                    resources.outputBuffer = data.outputBuffer;
+                    ExecuteSSGITrace(ctx.cmd, data.parameters, resources);
+                });
+                return passData.outputBuffer;
+            }
+        }
+
+        class UpscaleSSGIPassData
+        {
+            public SSGIUpscaleParameters parameters;
+            public TextureHandle depthTexture;
+            public TextureHandle inputBuffer;
+            public TextureHandle outputBuffer;
+        }
+
+        TextureHandle UpscaleSSGI(RenderGraph renderGraph, HDCamera hdCamera, GlobalIllumination giSettings, TextureHandle depthPyramid, TextureHandle inputBuffer)
+        {
+            using (var builder = renderGraph.AddRenderPass<UpscaleSSGIPassData>("Upscale SSGI", out var passData, ProfilingSampler.Get(HDProfileId.SSGIUpscale)))
+            {
+                builder.EnableAsyncCompute(false);
+
+                passData.parameters = PrepareSSGIUpscaleParameters(hdCamera, giSettings); ;
+                passData.depthTexture = builder.ReadTexture(depthPyramid);
+                passData.inputBuffer = builder.ReadTexture(inputBuffer);
+                passData.outputBuffer = builder.WriteTexture(renderGraph.CreateTexture(new TextureDesc(Vector2.one, true, true)
+                { colorFormat = GraphicsFormat.R16G16B16A16_SFloat, enableRandomWrite = true, name = "SSGI Final" }));
+
+                builder.SetRenderFunc(
+                (UpscaleSSGIPassData data, RenderGraphContext ctx) =>
+                {
+                    // We need to fill the structure that holds the various resources
+                    SSGIUpscaleResources resources = new SSGIUpscaleResources();
+                    resources.depthTexture = data.depthTexture;
+                    resources.inputBuffer = data.inputBuffer;
+                    resources.outputBuffer = data.outputBuffer;
+                    ExecuteSSGIUpscale(ctx.cmd, data.parameters, resources);
+                });
+                return passData.outputBuffer;
+            }
+        }
+
+        TextureHandle RenderSSGI(RenderGraph renderGraph, HDCamera hdCamera, TextureHandle depthPyramid, TextureHandle normalBuffer, TextureHandle motionVectorsBuffer, ShaderVariablesRaytracing shaderVariablesRayTracingCB)
+        {
+            // Grab the global illumination volume component
+            GlobalIllumination giSettings = hdCamera.volumeStack.GetComponent<GlobalIllumination>();
+
+            using (new RenderGraphProfilingScope(renderGraph, ProfilingSampler.Get(HDProfileId.SSGIPass)))
+            {
+                // Trace the signal
+                TextureHandle colorBuffer = TraceSSGI(renderGraph, hdCamera, giSettings, depthPyramid, normalBuffer, motionVectorsBuffer);
+
+                // Denoise the signal
+                float historyValidity = EvaluateHistoryValidity(hdCamera);
+                SSGIDenoiser ssgiDenoiser = GetSSGIDenoiser();
+                ssgiDenoiser.Denoise(renderGraph, hdCamera, depthPyramid, normalBuffer, motionVectorsBuffer, colorBuffer, !giSettings.fullResolutionSS, historyValidity: historyValidity);
+
+                // Upscale it if required
+                // If this was a half resolution effect, we still have to upscale it
+                if (!giSettings.fullResolutionSS)
+                    colorBuffer = UpscaleSSGI(renderGraph, hdCamera, giSettings, depthPyramid, colorBuffer);
+                return colorBuffer;
+            }
+        }
+    }
+}