Ported velocity factor and exposure clear value from FSR 3.1.1 code

Runtime/FSR3/Fsr3Upscaler.cs

@@ -265,6 +265,8 @@ namespace FidelityFX.FSR3
             public float deltaPreExposure;
             public float viewSpaceToMetersFactor;
             public float frameIndex;
+
+            public float velocityFactor;
         }
         
         [Serializable, StructLayout(LayoutKind.Sequential)]

Runtime/FSR3/Fsr3UpscalerContext.cs

@@ -34,6 +34,11 @@ namespace FidelityFX.FSR3
     public class Fsr3UpscalerContext
     {
         private const int MaxQueuedFrames = 16;
+
+        public float VelocityFactor
+        {
+            set => UpscalerConsts.velocityFactor = Mathf.Clamp01(value);
+        }
         
         private Fsr3Upscaler.ContextDescription _contextDescription;
         private CommandBuffer _commandBuffer;
@@ -96,6 +101,7 @@ namespace FidelityFX.FSR3
             _resourceFrameIndex = 0;
             
             UpscalerConsts.maxUpscaleSize = _contextDescription.MaxUpscaleSize;
+            UpscalerConsts.velocityFactor = 1.0f;
             
             _resources.Create(_contextDescription);
             CreatePasses();
@@ -232,7 +238,7 @@ namespace FidelityFX.FSR3
                 
                 // Auto exposure always used to track luma changes in locking logic
                 commandBuffer.SetRenderTarget(_resources.FrameInfo);
-                commandBuffer.ClearRenderTarget(false, true, new Color(0f, 1e8f, 0f, 0f));
+                commandBuffer.ClearRenderTarget(false, true, new Color(0f, 1f, 0f, 0f));
 
                 // Reset atomic counter to 0
                 commandBuffer.SetRenderTarget(_resources.SpdAtomicCounter);