Reworked dispatching code to use the common SPD and depth params methods.

Runtime/FrameInterpolation/FrameInterpolation.cs

@@ -166,14 +166,5 @@ namespace FidelityFX.FrameGen
             public Vector2 jitter;
             public Vector2 motionVectorScale;
         }
-
-        [Serializable, StructLayout(LayoutKind.Sequential)]
-        internal struct InpaintingPyramidConstants
-        {
-            public uint mips;
-            public uint numWorkGroups;
-            public uint workGroupOffsetX;
-            public uint workGroupOffsetY;
-        }
     }
 }

Runtime/FrameInterpolation/FrameInterpolationContext.cs

@@ -26,7 +26,7 @@ namespace FidelityFX.FrameGen
         private readonly FrameInterpolationResources _resources = new FrameInterpolationResources();
 
         private readonly ConstantsBuffer<FrameInterpolation.Constants> _frameInterpolationConstants = new ConstantsBuffer<FrameInterpolation.Constants>();
-        private readonly ConstantsBuffer<FrameInterpolation.InpaintingPyramidConstants> _spdConstants = new ConstantsBuffer<FrameInterpolation.InpaintingPyramidConstants>();
+        private readonly ConstantsBuffer<FfxSpd.SpdConstants> _spdConstants = new ConstantsBuffer<FfxSpd.SpdConstants>();
         
         private readonly CustomSampler _sampler = CustomSampler.Create("Frame Interpolation");
         private readonly CustomSampler _prepareSampler = CustomSampler.Create("Frame Interpolation - Prepare");
@@ -172,7 +172,11 @@ namespace FidelityFX.FrameGen
             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);
+            
+            bool inverted = (_contextDescription.flags & FrameInterpolation.InitializationFlags.EnableDepthInverted) != 0;
+            bool infinite = (_contextDescription.flags & FrameInterpolation.InitializationFlags.EnableDepthInfinite) != 0;
+            constants.deviceToViewDepth = FfxUtils.SetupDeviceDepthToViewSpaceDepthParams(
+                dispatchDescription.renderSize, dispatchDescription.cameraNear, dispatchDescription.cameraFar, dispatchDescription.cameraFovAngleVertical, inverted, infinite);
             
             _frameInterpolationConstants.UpdateBufferData(commandBuffer);
             
@@ -196,7 +200,6 @@ namespace FidelityFX.FrameGen
             if (executePreparationPasses)
             {
                 // Clear estimated depth resources
-                bool inverted = (_contextDescription.flags & FrameInterpolation.InitializationFlags.EnableDepthInverted) == FrameInterpolation.InitializationFlags.EnableDepthInverted;
                 commandBuffer.SetRenderTarget(_resources.ReconstructedDepthInterpolatedFrame);
                 commandBuffer.ClearRenderTarget(false, true, inverted ? Color.clear : Color.white);
                 
@@ -236,66 +239,11 @@ namespace FidelityFX.FrameGen
             _gameVectorFieldInpaintingPyramidPass.ScheduleDispatch(commandBuffer, dispatchDescription, doubleBufferId, dispatchThreadGroupCount.x, dispatchThreadGroupCount.y);
         }
         
-        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 void SetupSpdConstants(Vector2Int resolution, out Vector2Int dispatchThreadGroupCount)
         {
-            RectInt rectInfo = new RectInt(0, 0, resolution.x, resolution.y);
-            SpdSetup(rectInfo, out dispatchThreadGroupCount, out var workGroupOffset, out var numWorkGroupsAndMips);
-            
-            ref FrameInterpolation.InpaintingPyramidConstants spdConstants = ref _spdConstants.Value;
-            spdConstants.numWorkGroups = (uint)numWorkGroupsAndMips.x;
-            spdConstants.mips = (uint)Math.Min(numWorkGroupsAndMips.y, 7);
-            spdConstants.workGroupOffsetX = (uint)workGroupOffset.x;
-            spdConstants.workGroupOffsetY = (uint)workGroupOffset.y;
-        }
-
-        private static void SpdSetup(RectInt rectInfo, out Vector2Int dispatchThreadGroupCount, out Vector2Int workGroupOffset, out Vector2Int numWorkGroupsAndMips, int mips = -1)
-        {
-            workGroupOffset = new Vector2Int(rectInfo.x / 64, rectInfo.y / 64);
-
-            int endIndexX = (rectInfo.x + rectInfo.width - 1) / 64;
-            int endIndexY = (rectInfo.y + rectInfo.height - 1) / 64;
-
-            dispatchThreadGroupCount = new Vector2Int(endIndexX + 1 - workGroupOffset.x, endIndexY + 1 - workGroupOffset.y);
-
-            numWorkGroupsAndMips = new Vector2Int(dispatchThreadGroupCount.x * dispatchThreadGroupCount.y, mips);
-            if (mips < 0)
-            {
-                float resolution = Math.Max(rectInfo.width, rectInfo.height);
-                numWorkGroupsAndMips.y = Math.Min(Mathf.FloorToInt(Mathf.Log(resolution, 2.0f)), 12);
-            }
+            ref var spdConstants = ref _spdConstants.Value;
+            FfxSpd.SetupSpdConstants(resolution, ref spdConstants, out dispatchThreadGroupCount);
+            spdConstants.mips = Math.Min(spdConstants.mips, 7);
         }
 
         private int _debugIndex = 0;

Runtime/FrameInterpolation/FrameInterpolationPass.cs

@@ -288,7 +288,7 @@ namespace FidelityFX.FrameGen
             BindMipmap(commandBuffer, FrameInterpolationShaderIDs.UavInpaintingPyramidMipmap6, Resources.InpaintingPyramid, 6);
             
             commandBuffer.SetComputeConstantBufferParam(ComputeShader, FrameInterpolationShaderIDs.CbFrameInterpolation, Constants, 0, Marshal.SizeOf<FrameInterpolation.Constants>());
-            commandBuffer.SetComputeConstantBufferParam(ComputeShader, FrameInterpolationShaderIDs.CbInpaintingPyramid, _spdConstants, 0, Marshal.SizeOf<FrameInterpolation.InpaintingPyramidConstants>());
+            commandBuffer.SetComputeConstantBufferParam(ComputeShader, FrameInterpolationShaderIDs.CbInpaintingPyramid, _spdConstants, 0, Marshal.SizeOf<FfxSpd.SpdConstants>());
             
             commandBuffer.DispatchCompute(ComputeShader, KernelIndex, dispatchX, dispatchY, dispatchZ);
         }
@@ -348,7 +348,7 @@ namespace FidelityFX.FrameGen
             BindMipmap(commandBuffer, FrameInterpolationShaderIDs.UavInpaintingPyramidMipmap6, Resources.InpaintingPyramid, 6);
             
             commandBuffer.SetComputeConstantBufferParam(ComputeShader, FrameInterpolationShaderIDs.CbFrameInterpolation, Constants, 0, Marshal.SizeOf<FrameInterpolation.Constants>());
-            commandBuffer.SetComputeConstantBufferParam(ComputeShader, FrameInterpolationShaderIDs.CbInpaintingPyramid, _spdConstants, 0, Marshal.SizeOf<FrameInterpolation.InpaintingPyramidConstants>());
+            commandBuffer.SetComputeConstantBufferParam(ComputeShader, FrameInterpolationShaderIDs.CbInpaintingPyramid, _spdConstants, 0, Marshal.SizeOf<FfxSpd.SpdConstants>());
             
             commandBuffer.DispatchCompute(ComputeShader, KernelIndex, dispatchX, dispatchY, dispatchZ);
         }

Runtime/OpticalFlow/OpticalFlow.cs

@@ -103,10 +103,7 @@ namespace FidelityFX.FrameGen
         [Serializable, StructLayout(LayoutKind.Sequential)]
         internal struct SpdConstants
         {
-            public uint mips;
-            public uint numWorkGroups;
-            public uint workGroupOffsetX;
-            public uint workGroupOffsetY;
+            public FfxSpd.SpdConstants spd;
 
             public uint numWorkGroupsOpticalFlowInputPyramid;
             public uint pad0_;

Runtime/OpticalFlow/OpticalFlowContext.cs

@@ -217,32 +217,9 @@ namespace FidelityFX.FrameGen
         {
             const int resolutionMultiplier = 1;
             
-            RectInt rectInfo = new RectInt(0, 0, _contextDescription.resolution.x * resolutionMultiplier, _contextDescription.resolution.y * resolutionMultiplier);
-            SpdSetup(rectInfo, out dispatchThreadGroupCount, out var workGroupOffset, out var numWorkGroupsAndMips, 4);
-            
             ref OpticalFlow.SpdConstants spdConstants = ref _spdConstants.Value;
-            spdConstants.numWorkGroups = (uint)numWorkGroupsAndMips.x;
-            spdConstants.mips = (uint)numWorkGroupsAndMips.y;
-            spdConstants.workGroupOffsetX = (uint)workGroupOffset.x;
-            spdConstants.workGroupOffsetY = (uint)workGroupOffset.y;
-            spdConstants.numWorkGroupsOpticalFlowInputPyramid = (uint)numWorkGroupsAndMips.x;
-        }
-
-        private static void SpdSetup(RectInt rectInfo, out Vector2Int dispatchThreadGroupCount, out Vector2Int workGroupOffset, out Vector2Int numWorkGroupsAndMips, int mips = -1)
-        {
-            workGroupOffset = new Vector2Int(rectInfo.x / 64, rectInfo.y / 64);
-
-            int endIndexX = (rectInfo.x + rectInfo.width - 1) / 64;
-            int endIndexY = (rectInfo.y + rectInfo.height - 1) / 64;
-
-            dispatchThreadGroupCount = new Vector2Int(endIndexX + 1 - workGroupOffset.x, endIndexY + 1 - workGroupOffset.y);
-
-            numWorkGroupsAndMips = new Vector2Int(dispatchThreadGroupCount.x * dispatchThreadGroupCount.y, mips);
-            if (mips < 0)
-            {
-                float resolution = Math.Max(rectInfo.width, rectInfo.height);
-                numWorkGroupsAndMips.y = Math.Min(Mathf.FloorToInt(Mathf.Log(resolution, 2.0f)), 12);
-            }
+            FfxSpd.SetupSpdConstants(_contextDescription.resolution * resolutionMultiplier, ref spdConstants.spd, out dispatchThreadGroupCount);
+            spdConstants.numWorkGroupsOpticalFlowInputPyramid = spdConstants.spd.numWorkGroups;
         }
 
         private static void DestroyPass(ref OpticalFlowPass pass)