Fix for potentially corrupted refraction result on xbox (#1699)

* try explicit NaN check

* Typo

* Add comment

* changelog

Co-authored-by: sebastienlagarde <sebastien@unity3d.com>

Author: FrancescoC-unity

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

@@ -64,6 +64,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
 - Fixed issue with updating the compositor output when not in play mode (case 1266216)
 - Fixed warning with area mesh (case 1268379)
 - Fixed issue with diffusion profile not being updated upon reset of the editor. 
+- Fixed an issue that lead to corrupted refraction in some scenarios on xbox.
 
 ### Changed
 - Preparation pass for RTSSShadows to be supported by render graph.

com.unity.render-pipelines.high-definition/Runtime/Lighting/Reflection/VolumeProjection.hlsl

@@ -27,6 +27,9 @@ float IntersectSphereProxy(EnvLightData lightData, float3 dirPS, float3 position
 {
     float sphereOuterDistance = lightData.proxyExtents.x;
     float projectionDistance = IntersectRaySphereSimple(positionPS, dirPS, sphereOuterDistance);
+    projectionDistance = IsNaN(projectionDistance) ? -1.0f : projectionDistance; // Note that because we use IntersectRaySphereSimple, in case of a ill-set proxy, it could be that
+                                                                                // the determinant in the ray-sphere intersection code ends up negative, leading to a NaN.
+                                                                                // Rather than complicating the IntersectRaySphereSimple or switching to a more complex case, we cover that case this way.
     projectionDistance = max(projectionDistance, lightData.minProjectionDistance); // Setup projection to infinite if requested (mean no projection shape)
 
     return projectionDistance;