Making a 3D depth shader
I will leave this here as I struggled a bit to achieve this and there doesn't seem to be an awful lot of documentation online for it.
I'm making a game about learning to drive an ancient underwater vessel to escape a dangerous cave, and I want the player to be able to see using only a set of cameras that can provide a depth view of the environment around them.
I finally got it, this is the shader graph configuration and a picture of the cave system with it!