I have an effect that renders a skybox and fog at the end of the opaque queue, using OnRenderImage and [ImageEffectOpaque]. I'm trying to get this effect to work with Single-Pass Stereo, but it seems that it's not behaving the same way OnRenderImage works without [ImageEffectOpaque]. Instead of executing my shader once per eye, it's executed once for the whole buffer. Also, unity_StereoScaleOffset, unity_StereoEyeIndex, and _MainTex_ST don't contain any useful data. The biggest problem I'm having is going from screenspace back to worldSpace, so I can sample the skybox texture. Which matrices should I use for this? When doing a graphics capture, I see that there are borders around the left and right eye buffers. What's the purpose of these buffers? How can I programatically determine the size of these borders? Is there documentation available for Single-Pass integration?