Add matrix parameter to SnapAndTransitionVertLayout

Also brings up-to-date with downstream.

crest/Assets/Crest/Crest/Shaders/OceanVertHelpers.hlsl

@@ -31,13 +31,20 @@ float ComputeLodAlpha(float3 i_worldPos, float i_meshScaleAlpha, in const Cascad
 	return lodAlpha;
 }
 
-void SnapAndTransitionVertLayout(in const float i_meshScaleAlpha, in const CascadeParams i_cascadeData0, in const float i_geometryGridSize, inout float3 io_worldPos, out float o_lodAlpha)
+void SnapAndTransitionVertLayout(in const float4x4 i_objectMatrix, in const float i_meshScaleAlpha, in const CascadeParams i_cascadeData0, in const float i_geometryGridSize, inout float3 io_worldPos, out float o_lodAlpha)
 {
 	const float GRID_SIZE_2 = 2.0 * i_geometryGridSize, GRID_SIZE_4 = 4.0 * i_geometryGridSize;
 
 	// snap the verts to the grid
 	// The snap size should be twice the original size to keep the shape of the eight triangles (otherwise the edge layout changes).
-	io_worldPos.xz -= frac(UNITY_MATRIX_M._m03_m23 / GRID_SIZE_2) * GRID_SIZE_2; // caution - sign of frac might change in non-hlsl shaders
+	float2 objectPosXZWS = i_objectMatrix._m03_m23;
+
+	// Relative world space - add camera pos to get back out to world. Would be nice if we could operate in RWS..
+#if (SHADEROPTIONS_CAMERA_RELATIVE_RENDERING != 0)
+	objectPosXZWS += _WorldSpaceCameraPos.xz;
+#endif
+
+	io_worldPos.xz -= frac(objectPosXZWS / GRID_SIZE_2) * GRID_SIZE_2; // caution - sign of frac might change in non-hlsl shaders
 
 	// compute lod transition alpha
 	o_lodAlpha = ComputeLodAlpha(io_worldPos, i_meshScaleAlpha, i_cascadeData0);
@@ -53,4 +60,9 @@ void SnapAndTransitionVertLayout(in const float i_meshScaleAlpha, in const Casca
 	if (abs(offset.y) < minRadius) io_worldPos.z += offset.y * o_lodAlpha * GRID_SIZE_4;
 }
 
+void SnapAndTransitionVertLayout(in const float i_meshScaleAlpha, in const CascadeParams i_cascadeData0, in const float i_geometryGridSize, inout float3 io_worldPos, out float o_lodAlpha)
+{
+	SnapAndTransitionVertLayout(UNITY_MATRIX_M, i_meshScaleAlpha, i_cascadeData0, i_geometryGridSize, io_worldPos, o_lodAlpha);
+}
+
 #endif // CREST_OCEAN_VERT_HELPERS_H