Implemented prepare process and started on main dispatch

Runtime/FrameInterpolation/FrameInterpolation.cs

@@ -41,7 +41,7 @@ namespace FidelityFX.FrameGen
             public Vector2Int displaySize;
             public Vector2Int renderSize;
             public ResourceView currentBackBuffer;
-            public ResourceView currentBackBuffer_HUDLess;
+            public ResourceView currentBackBuffer_HUDLess;  // Optional
             public ResourceView output;
 
             public RectInt interpolationRect;

Runtime/FrameInterpolation/FrameInterpolationContext.cs

@@ -1,5 +1,6 @@
 using System.Runtime.InteropServices;
 using UnityEngine;
+using UnityEngine.Assertions;
 using UnityEngine.Profiling;
 using UnityEngine.Rendering;
 
@@ -47,6 +48,8 @@ namespace FidelityFX.FrameGen
             _spdConstantsBuffer = CreateConstantBuffer<FrameInterpolation.InpaintingPyramidConstants>();
 
             _firstExecution = true;
+            _dispatchCount = 0;
+            _previousFrameID = 0;
             _asyncSupported = (_contextDescription.flags & FrameInterpolation.InitializationFlags.EnableAsyncSupport) == FrameInterpolation.InitializationFlags.EnableAsyncSupport;
 
             Constants.maxRenderSize = _contextDescription.maxRenderSize;
@@ -98,6 +101,30 @@ namespace FidelityFX.FrameGen
         public void Prepare(CommandBuffer commandBuffer, FrameInterpolation.PrepareDescription prepareDescription)
         {
             commandBuffer.BeginSample(_prepareSampler);
+
+            int doubleBufferId = _asyncSupported ? (int)(prepareDescription.frameID & 1) : 0;
+
+            Constants.renderSize = prepareDescription.renderSize;
+            Constants.jitter = prepareDescription.jitterOffset;
+            Vector2Int motionVectorsTargetSize = (_contextDescription.flags & FrameInterpolation.InitializationFlags.EnableDisplayResolutionMotionVectors) != 0 ? Constants.displaySize : Constants.renderSize;
+            Constants.motionVectorScale.x = prepareDescription.motionVectorScale.x / motionVectorsTargetSize.x;
+            Constants.motionVectorScale.y = prepareDescription.motionVectorScale.y / motionVectorsTargetSize.y;
+            
+            commandBuffer.SetBufferData(_frameInterpolationConstantsBuffer, _frameInterpolationConstantsArray);
+            
+            Assert.IsTrue(prepareDescription.depth.IsValid);
+            Assert.IsTrue(prepareDescription.motionVectors.IsValid);
+            
+            // clear estimated depth resources
+            {
+                bool inverted = (_contextDescription.flags & FrameInterpolation.InitializationFlags.EnableDepthInverted) == FrameInterpolation.InitializationFlags.EnableDepthInverted;
+                commandBuffer.SetRenderTarget(_resources.ReconstructedDepth[doubleBufferId]);
+                commandBuffer.ClearRenderTarget(false, true, inverted ? Color.clear : Color.white);
+            }
+
+            int renderDispatchSizeX = (prepareDescription.renderSize.x + 7) / 8;
+            int renderDispatchSizeY = (prepareDescription.renderSize.y + 7) / 8;
+            ((FrameInterpolationReconstructAndDilatePass)_reconstructAndDilatePass).ScheduleDispatch(commandBuffer, prepareDescription, doubleBufferId, renderDispatchSizeX, renderDispatchSizeY);
             
             commandBuffer.EndSample(_prepareSampler);
         }
@@ -105,10 +132,117 @@ namespace FidelityFX.FrameGen
         public void Dispatch(CommandBuffer commandBuffer, FrameInterpolation.DispatchDescription dispatchDescription)
         {
             commandBuffer.BeginSample(_sampler);
+
+            bool reset = _dispatchCount == 0 || dispatchDescription.reset;
+            Assert.IsTrue(!_asyncSupported || reset || dispatchDescription.frameID > _previousFrameID,
+                "When async support is enabled, and the reset flag is not set, frame ID must increment in each dispatch.");
+
+            bool frameIdDecreased = dispatchDescription.frameID < _previousFrameID;
+            bool frameIdSkipped = (dispatchDescription.frameID - _previousFrameID) > 1;
+            bool disjointFrameId = frameIdDecreased || frameIdSkipped;
+            _previousFrameID = dispatchDescription.frameID;
+            _dispatchCount++;   // TODO: this is pointless, it does the same as _firstExecution, no need to do any counting
+
+            Constants.renderSize = dispatchDescription.renderSize;
+            Constants.displaySize = dispatchDescription.displaySize;
+            Constants.displaySizeRcp.x = 1.0f / dispatchDescription.displaySize.x;
+            Constants.displaySizeRcp.y = 1.0f / dispatchDescription.displaySize.y;
+            Constants.upscalerTargetSize = dispatchDescription.interpolationRect.size;
+            Constants.mode = 0;
+            Constants.reset = (reset || disjointFrameId) ? 1 : 0;
+            Constants.deltaTime = dispatchDescription.frameTimeDelta;
+            Constants.HUDLessAttachedFactor = dispatchDescription.currentBackBuffer_HUDLess.IsValid ? 1 : 0;
+
+            Constants.opticalFlowScale = dispatchDescription.opticalFlowScale;
+            Constants.opticalFlowBlockSize = dispatchDescription.opticalFlowBlockSize;
+            Constants.dispatchFlags = (uint)dispatchDescription.flags;
+
+            Constants.cameraNear = dispatchDescription.cameraNear;
+            Constants.cameraFar = dispatchDescription.cameraFar;
+
+            Constants.interpolationRectBase = dispatchDescription.interpolationRect.position;
+            Constants.interpolationRectSize = dispatchDescription.interpolationRect.size;
+
+            // Debug bar
+            Constants.debugBarColor.x = DebugBarColorSequence[_debugIndex * 3 + 0];
+            Constants.debugBarColor.y = DebugBarColorSequence[_debugIndex * 3 + 1];
+            Constants.debugBarColor.z = DebugBarColorSequence[_debugIndex * 3 + 2];
+            _debugIndex = (_debugIndex + 1) % (DebugBarColorSequence.Length / 3);
+
+            Constants.backBufferTransferFunction = (uint)dispatchDescription.backbufferTransferFunction;
+            Constants.minMaxLuminance = dispatchDescription.minMaxLuminance;
+
+            float aspectRatio = dispatchDescription.renderSize.x / (float)dispatchDescription.renderSize.y;
+            float cameraAngleHorizontal = Mathf.Atan(Mathf.Tan(dispatchDescription.cameraFovAngleVertical / 2) * aspectRatio) * 2;
+            Constants.tanHalfFOV = Mathf.Tan(cameraAngleHorizontal * 0.5f);
+            Constants.deviceToViewDepth = SetupDeviceDepthToViewSpaceDepthParams(dispatchDescription);
+            
+            commandBuffer.SetBufferData(_frameInterpolationConstantsBuffer, _frameInterpolationConstantsArray);
+            
+            int doubleBufferId = _asyncSupported ? (int)(dispatchDescription.frameID & 1) : 0;
+            
+            int displayDispatchSizeX = (dispatchDescription.displaySize.x + 7) / 8;
+            int displayDispatchSizeY = (dispatchDescription.displaySize.y + 7) / 8;
+
+            int renderDispatchSizeX = (dispatchDescription.renderSize.x + 7) / 8;
+            int renderDispatchSizeY = (dispatchDescription.renderSize.y + 7) / 8;
+
+            int opticalFlowDispatchSizeX = (int)(dispatchDescription.displaySize.x / (float)dispatchDescription.opticalFlowBlockSize + 7) / 8;
+            int opticalFlowDispatchSizeY = (int)(dispatchDescription.displaySize.y / (float)dispatchDescription.opticalFlowBlockSize + 7) / 8;
+
+            bool executePreparationPasses = (Constants.reset == 0);
+            
+            // Schedule work for the interpolation command list
+            // TODO
             
             commandBuffer.EndSample(_sampler);
         }
         
+        private Vector4 SetupDeviceDepthToViewSpaceDepthParams(FrameInterpolation.DispatchDescription dispatchParams)
+        {
+            bool inverted = (_contextDescription.flags & FrameInterpolation.InitializationFlags.EnableDepthInverted) != 0;
+            bool infinite = (_contextDescription.flags & FrameInterpolation.InitializationFlags.EnableDepthInfinite) != 0;
+
+            // make sure it has no impact if near and far plane values are swapped in dispatch params
+            // the flags "inverted" and "infinite" will decide what transform to use
+            float min = Mathf.Min(dispatchParams.cameraNear, dispatchParams.cameraFar);
+            float max = Mathf.Max(dispatchParams.cameraNear, dispatchParams.cameraFar);
+
+            if (inverted)
+            {
+                (min, max) = (max, min);
+            }
+
+            float q = max / (min - max);
+            float d = -1.0f;
+
+            Vector4 matrixElemC = new Vector4(q, -1.0f - Mathf.Epsilon, q, 0.0f + Mathf.Epsilon);
+            Vector4 matrixElemE = new Vector4(q * min, -min - Mathf.Epsilon, q * min, max);
+            
+            // Revert x and y coords
+            float aspect = (float)dispatchParams.renderSize.x / dispatchParams.renderSize.y;
+            float cotHalfFovY = Mathf.Cos(0.5f * dispatchParams.cameraFovAngleVertical) / Mathf.Sin(0.5f * dispatchParams.cameraFovAngleVertical);
+
+            int matrixIndex = (inverted ? 2 : 0) + (infinite ? 1 : 0);
+            return new Vector4(
+                d * matrixElemC[matrixIndex],
+                matrixElemE[matrixIndex],
+                aspect / cotHalfFovY,
+                1.0f / cotHalfFovY);
+        }
+
+        private int _debugIndex = 0;
+        private static readonly float[] DebugBarColorSequence =
+        {
+            0.0f, 1.0f, 1.0f, // teal
+            1.0f, 0.42f, 0.0f, // orange
+            0.0f, 0.16f, 1.0f, // blue
+            0.74f, 1.0f, 0.0f, // lime
+            0.68f, 0.0f, 1.0f, // purple
+            0.0f, 1.0f, 0.1f, // green
+            1.0f, 1.0f, 0.48f // bright yellow
+        };
+        
         private static ComputeBuffer CreateConstantBuffer<TConstants>() where TConstants: struct
         {
             return new ComputeBuffer(1, Marshal.SizeOf<TConstants>(), ComputeBufferType.Constant);

Runtime/FrameInterpolation/FrameInterpolationPass.cs

@@ -17,8 +17,6 @@ namespace FidelityFX.FrameGen
         
         protected CustomSampler Sampler;
 
-        protected bool AsyncSupported => (ContextDescription.flags & FrameInterpolation.InitializationFlags.EnableAsyncSupport) == FrameInterpolation.InitializationFlags.EnableAsyncSupport;
-        
         protected FrameInterpolationPass(FrameInterpolation.ContextDescription contextDescription, FrameInterpolationResources resources, ComputeBuffer constants)
         {
             ContextDescription = contextDescription;
@@ -84,10 +82,8 @@ namespace FidelityFX.FrameGen
         {
         }
 
-        public void ScheduleDispatch(CommandBuffer commandBuffer, FrameInterpolation.PrepareDescription prepareParams, int frameIndex, int dispatchX, int dispatchY, int dispatchZ)
+        public void ScheduleDispatch(CommandBuffer commandBuffer, FrameInterpolation.PrepareDescription prepareParams, int frameIndex, int dispatchX, int dispatchY, int dispatchZ = 1)
         {
-            int doubleBufferId = AsyncSupported ? frameIndex : 0;
-            
             commandBuffer.BeginSample(Sampler);
 
             ref var mvs = ref prepareParams.motionVectors;
@@ -95,9 +91,9 @@ namespace FidelityFX.FrameGen
             commandBuffer.SetComputeTextureParam(ComputeShader, KernelIndex, FrameInterpolationShaderIDs.SrvInputMotionVectors, mvs.RenderTarget, mvs.MipLevel, mvs.SubElement);
             commandBuffer.SetComputeTextureParam(ComputeShader, KernelIndex, FrameInterpolationShaderIDs.SrvInputDepth, depth.RenderTarget, depth.MipLevel, depth.SubElement);
 
-            commandBuffer.SetComputeTextureParam(ComputeShader, KernelIndex, FrameInterpolationShaderIDs.UavReconstructedDepthPreviousFrame, Resources.ReconstructedDepth[doubleBufferId]);
-            commandBuffer.SetComputeTextureParam(ComputeShader, KernelIndex, FrameInterpolationShaderIDs.UavDilatedMotionVectors, Resources.DilatedMotionVectors[doubleBufferId]);
-            commandBuffer.SetComputeTextureParam(ComputeShader, KernelIndex, FrameInterpolationShaderIDs.UavDilatedDepth, Resources.DilatedDepth[doubleBufferId]);
+            commandBuffer.SetComputeTextureParam(ComputeShader, KernelIndex, FrameInterpolationShaderIDs.UavReconstructedDepthPreviousFrame, Resources.ReconstructedDepth[frameIndex]);
+            commandBuffer.SetComputeTextureParam(ComputeShader, KernelIndex, FrameInterpolationShaderIDs.UavDilatedMotionVectors, Resources.DilatedMotionVectors[frameIndex]);
+            commandBuffer.SetComputeTextureParam(ComputeShader, KernelIndex, FrameInterpolationShaderIDs.UavDilatedDepth, Resources.DilatedDepth[frameIndex]);
             
             commandBuffer.SetComputeConstantBufferParam(ComputeShader, FrameInterpolationShaderIDs.CbFrameInterpolation, Constants, 0, Marshal.SizeOf<FrameInterpolation.Constants>());
             
@@ -143,11 +139,9 @@ namespace FidelityFX.FrameGen
 
         protected override void DoScheduleDispatch(CommandBuffer commandBuffer, FrameInterpolation.DispatchDescription dispatchParams, int frameIndex, int dispatchX, int dispatchY, int dispatchZ)
         {
-            int doubleBufferId = AsyncSupported ? frameIndex : 0;
-            
             // TODO: verify that we need the buffers from *this* frame (probably yes)
-            commandBuffer.SetComputeTextureParam(ComputeShader, KernelIndex, FrameInterpolationShaderIDs.SrvDilatedMotionVectors, Resources.DilatedMotionVectors[doubleBufferId]);
-            commandBuffer.SetComputeTextureParam(ComputeShader, KernelIndex, FrameInterpolationShaderIDs.SrvDilatedDepth, Resources.DilatedDepth[doubleBufferId]);
+            commandBuffer.SetComputeTextureParam(ComputeShader, KernelIndex, FrameInterpolationShaderIDs.SrvDilatedMotionVectors, Resources.DilatedMotionVectors[frameIndex]);
+            commandBuffer.SetComputeTextureParam(ComputeShader, KernelIndex, FrameInterpolationShaderIDs.SrvDilatedDepth, Resources.DilatedDepth[frameIndex]);
             BindCurrentInterpolationSource(commandBuffer, dispatchParams);
 
             commandBuffer.SetComputeTextureParam(ComputeShader, KernelIndex, FrameInterpolationShaderIDs.UavReconstructedDepthInterpolatedFrame, Resources.ReconstructedDepthInterpolatedFrame);
@@ -168,10 +162,8 @@ namespace FidelityFX.FrameGen
 
         protected override void DoScheduleDispatch(CommandBuffer commandBuffer, FrameInterpolation.DispatchDescription dispatchParams, int frameIndex, int dispatchX, int dispatchY, int dispatchZ)
         {
-            int doubleBufferId = AsyncSupported ? frameIndex : 0;
-
-            commandBuffer.SetComputeTextureParam(ComputeShader, KernelIndex, FrameInterpolationShaderIDs.SrvDilatedMotionVectors, Resources.DilatedMotionVectors[doubleBufferId]);
-            commandBuffer.SetComputeTextureParam(ComputeShader, KernelIndex, FrameInterpolationShaderIDs.SrvDilatedDepth, Resources.DilatedDepth[doubleBufferId]);
+            commandBuffer.SetComputeTextureParam(ComputeShader, KernelIndex, FrameInterpolationShaderIDs.SrvDilatedMotionVectors, Resources.DilatedMotionVectors[frameIndex]);
+            commandBuffer.SetComputeTextureParam(ComputeShader, KernelIndex, FrameInterpolationShaderIDs.SrvDilatedDepth, Resources.DilatedDepth[frameIndex]);
             commandBuffer.SetComputeTextureParam(ComputeShader, KernelIndex, FrameInterpolationShaderIDs.SrvPreviousInterpolationSource, Resources.PreviousInterpolationSource);
             BindCurrentInterpolationSource(commandBuffer, dispatchParams);
 
@@ -194,7 +186,6 @@ namespace FidelityFX.FrameGen
 
         protected override void DoScheduleDispatch(CommandBuffer commandBuffer, FrameInterpolation.DispatchDescription dispatchParams, int frameIndex, int dispatchX, int dispatchY, int dispatchZ)
         {
-            int doubleBufferId = AsyncSupported ? frameIndex : 0;
             ref var ofVector = ref dispatchParams.opticalFlowVector;
 
             if (dispatchParams.opticalFlowScale.x > 0f)
@@ -204,7 +195,7 @@ namespace FidelityFX.FrameGen
 
             // TODO this might error... if so, bind an empty placeholder resource
             commandBuffer.SetComputeTextureParam(ComputeShader, KernelIndex, FrameInterpolationShaderIDs.SrvOpticalFlowConfidence, BuiltinRenderTextureType.None);
-            commandBuffer.SetComputeTextureParam(ComputeShader, KernelIndex, FrameInterpolationShaderIDs.SrvDilatedDepth, Resources.DilatedDepth[doubleBufferId]);
+            commandBuffer.SetComputeTextureParam(ComputeShader, KernelIndex, FrameInterpolationShaderIDs.SrvDilatedDepth, Resources.DilatedDepth[frameIndex]);
             commandBuffer.SetComputeTextureParam(ComputeShader, KernelIndex, FrameInterpolationShaderIDs.SrvPreviousInterpolationSource, Resources.PreviousInterpolationSource);
             BindCurrentInterpolationSource(commandBuffer, dispatchParams);
 
@@ -227,12 +218,10 @@ namespace FidelityFX.FrameGen
 
         protected override void DoScheduleDispatch(CommandBuffer commandBuffer, FrameInterpolation.DispatchDescription dispatchParams, int frameIndex, int dispatchX, int dispatchY, int dispatchZ)
         {
-            int doubleBufferId = AsyncSupported ? frameIndex : 0;
-            
             commandBuffer.SetComputeTextureParam(ComputeShader, KernelIndex, FrameInterpolationShaderIDs.SrvGameMotionVectorFieldX, Resources.GameMotionVectorFieldX);
             commandBuffer.SetComputeTextureParam(ComputeShader, KernelIndex, FrameInterpolationShaderIDs.SrvGameMotionVectorFieldY, Resources.GameMotionVectorFieldY);
-            commandBuffer.SetComputeTextureParam(ComputeShader, KernelIndex, FrameInterpolationShaderIDs.SrvReconstructedDepthPreviousFrame, Resources.ReconstructedDepth[doubleBufferId]);
-            commandBuffer.SetComputeTextureParam(ComputeShader, KernelIndex, FrameInterpolationShaderIDs.SrvDilatedDepth, Resources.DilatedDepth[doubleBufferId]);
+            commandBuffer.SetComputeTextureParam(ComputeShader, KernelIndex, FrameInterpolationShaderIDs.SrvReconstructedDepthPreviousFrame, Resources.ReconstructedDepth[frameIndex]);
+            commandBuffer.SetComputeTextureParam(ComputeShader, KernelIndex, FrameInterpolationShaderIDs.SrvDilatedDepth, Resources.DilatedDepth[frameIndex]);
             commandBuffer.SetComputeTextureParam(ComputeShader, KernelIndex, FrameInterpolationShaderIDs.SrvReconstructedDepthInterpolatedFrame, Resources.ReconstructedDepthInterpolatedFrame);
             commandBuffer.SetComputeTextureParam(ComputeShader, KernelIndex, FrameInterpolationShaderIDs.SrvInpaintingPyramid, Resources.InpaintingPyramid);