Shaders not working in VR/first person?

Hello all, I have a set of shaders that take an image, and highlight the edges and then choose certain pixels to stay on. ie:
Original Image:



First Shader:


Second shader:


It works fine when the camera has a set position, but when the camera moves it does weird stuff and I don't know why. It seems to run both shaders but the second one ends up getting flipped and displayed over the first one. Any ideas why this is happening?

 

The frame buffer can get flipped for all sorts of reasons. Most of this gets handled if you're using the built in

ComputeScreenPos

function, but sometimes it seems like Unity gets it wrong too.
https://docs.unity3d.com/Manual/SL-PlatformDifferences.html

Specifically that

UNITY_UV_STARTS_AT_TOP

stuff isn't implemented in any of the built in shaders, so you'll want to add that to your shader code manually.