Allocate double buffers only when async compute support is enabled

Runtime/FrameInterpolation/FrameInterpolationResources.cs

@@ -36,10 +36,12 @@ namespace FidelityFX.FrameGen
             OpticalFlowMotionVectorFieldY = CreateResource("FI_OpticalFlowMotionVectorFieldY", maxRenderSize, GraphicsFormat.R32_UInt);
             PreviousInterpolationSource = CreateResource("FI_PreviousInterpolationSource", displaySize, contextDescription.backBufferFormat);
             DisocclusionMask = CreateResource("FI_DisocclusionMask", maxRenderSize, GraphicsFormat.R8G8_UNorm);
-            
-            CreateDoubleBufferedResource(DilatedDepth, "FI_DilatedDepth_", maxRenderSize, GraphicsFormat.R32_SFloat);
-            CreateDoubleBufferedResource(DilatedMotionVectors, "FI_DilatedMVs_", maxRenderSize, GraphicsFormat.R16G16_SFloat);
-            CreateDoubleBufferedResource(ReconstructedDepth, "FI_ReconstructedDepth_", maxRenderSize, GraphicsFormat.R32_UInt);
+
+            // Double buffering is used only when async support is enabled
+            int numBuffers = (contextDescription.flags & FrameInterpolation.InitializationFlags.EnableAsyncSupport) != 0 ? 2 : 1;
+            CreateDoubleBufferedResource(DilatedDepth, "FI_DilatedDepth_", maxRenderSize, GraphicsFormat.R32_SFloat, numBuffers);
+            CreateDoubleBufferedResource(DilatedMotionVectors, "FI_DilatedMVs_", maxRenderSize, GraphicsFormat.R16G16_SFloat, numBuffers);
+            CreateDoubleBufferedResource(ReconstructedDepth, "FI_ReconstructedDepth_", maxRenderSize, GraphicsFormat.R32_UInt, numBuffers);
         }
         
         public void Destroy()
@@ -79,9 +81,9 @@ namespace FidelityFX.FrameGen
             return new ComputeBuffer(count, Marshal.SizeOf<TElem>());
         }
         
-        private static void CreateDoubleBufferedResource(RenderTexture[] resource, string name, Vector2Int size, GraphicsFormat format)
+        private static void CreateDoubleBufferedResource(RenderTexture[] resource, string name, Vector2Int size, GraphicsFormat format, int numElements = 2)
         {
-            for (int i = 0; i < 2; ++i)
+            for (int i = 0; i < numElements; ++i)
             {
                 resource[i] = new RenderTexture(size.x, size.y, 0, format) { name = name + (i + 1), enableRandomWrite = true };
                 resource[i].Create();