Use HDCamera modified stereo view matrices

This is to support camera relative rendering in stereo.  The modified view matrix propogates to the stereo versions of InvView and ViewProj.

ScriptableRenderPipeline/HDRenderPipeline/HDRP/Camera/HDCamera.cs

             var gpuNonJitteredProj = GL.GetGPUProjectionMatrix(nonJitteredCameraProj, true);
 
             var pos = camera.transform.position;
+
+            // TODO: Delete this?
             var relPos = pos; // World-origin-relative
 
             if (ShaderConfig.s_CameraRelativeRendering != 0)
             for (uint eyeIndex = 0; eyeIndex < 2; eyeIndex++)
             {
                 viewMatrixStereo[eyeIndex] = camera.GetStereoViewMatrix((Camera.StereoscopicEye)eyeIndex);
+                if (ShaderConfig.s_CameraRelativeRendering != 0)
+                {
+                    // Zero out the translation component.
+                    viewMatrixStereo[eyeIndex].SetColumn(3, new Vector4(0, 0, 0, 1));
+                }
+
 
                 projMatrixStereo[eyeIndex] = camera.GetStereoProjectionMatrix((Camera.StereoscopicEye)eyeIndex);
                 projMatrixStereo[eyeIndex] = GL.GetGPUProjectionMatrix(projMatrixStereo[eyeIndex], true);
 
         public void SetupGlobalStereoParams(CommandBuffer cmd)
         {
+            var viewProjStereo = new Matrix4x4[2];
+            var invViewStereo = new Matrix4x4[2];
             var invProjStereo = new Matrix4x4[2];
             var invViewProjStereo = new Matrix4x4[2];
 
                 invProjStereo[eyeIndex] = proj.inverse;
 
-                var vp = proj * viewMatrixStereo[eyeIndex];
-                invViewProjStereo[eyeIndex] = vp.inverse;
+                var view = viewMatrixStereo[eyeIndex];
+                invViewStereo[eyeIndex] = view.inverse;
+
+                viewProjStereo[eyeIndex] = proj * view;
+                invViewProjStereo[eyeIndex] = viewProjStereo[eyeIndex].inverse;
+            cmd.SetGlobalMatrixArray(HDShaderIDs._ViewMatrixStereo, viewMatrixStereo);
+            cmd.SetGlobalMatrixArray(HDShaderIDs._ViewProjMatrixStereo, viewProjStereo);
+            cmd.SetGlobalMatrixArray(HDShaderIDs._InvViewMatrixStereo, invViewStereo);
             cmd.SetGlobalMatrixArray(HDShaderIDs._InvProjMatrixStereo, invProjStereo);
             cmd.SetGlobalMatrixArray(HDShaderIDs._InvViewProjMatrixStereo, invViewProjStereo);
         }

ScriptableRenderPipeline/HDRenderPipeline/HDRP/HDStringConstants.cs

         public static readonly int _TaaFrameIndex    = Shader.PropertyToID("_TaaFrameIndex");
         public static readonly int _TaaFrameRotation = Shader.PropertyToID("_TaaFrameRotation");
 
+        public static readonly int _ViewMatrixStereo = Shader.PropertyToID("_ViewMatrixStereo");
+        public static readonly int _ViewProjMatrixStereo = Shader.PropertyToID("_ViewProjMatrixStereo");
+        public static readonly int _InvViewMatrixStereo = Shader.PropertyToID("_InvViewMatrixStereo");
         public static readonly int _InvProjMatrixStereo = Shader.PropertyToID("_InvProjMatrixStereo");
         public static readonly int _InvViewProjMatrixStereo = Shader.PropertyToID("_InvViewProjMatrixStereo");
 

ScriptableRenderPipeline/HDRenderPipeline/HDRP/ShaderVariables.hlsl

 #if defined(USING_STEREO_MATRICES)
 
 CBUFFER_START(UnityPerPassStereo)
+float4x4 _ViewMatrixStereo[2];
+// Proj not needed...yet?
+float4x4 _ViewProjMatrixStereo[2];
+float4x4 _InvViewMatrixStereo[2];
 float4x4 _InvProjMatrixStereo[2];
 float4x4 _InvViewProjMatrixStereo[2];
 CBUFFER_END

ScriptableRenderPipeline/HDRenderPipeline/HDRP/ShaderVariablesMatrixDefsHDCamera.hlsl

 
 #define UNITY_MATRIX_M     unity_ObjectToWorld
 #define UNITY_MATRIX_I_M   unity_WorldToObject
-#define UNITY_MATRIX_V     unity_StereoMatrixV[unity_StereoEyeIndex]
-#define UNITY_MATRIX_I_V   unity_StereoMatrixInvV[unity_StereoEyeIndex]
+#define UNITY_MATRIX_V     _ViewMatrixStereo[unity_StereoEyeIndex]
+#define UNITY_MATRIX_I_V   _InvViewMatrixStereo[unity_StereoEyeIndex]
-#define UNITY_MATRIX_VP    unity_StereoMatrixVP[unity_StereoEyeIndex]
+#define UNITY_MATRIX_VP    _ViewProjMatrixStereo[unity_StereoEyeIndex]
 #define UNITY_MATRIX_I_VP  _InvViewProjMatrixStereo[unity_StereoEyeIndex]
 
 #else