Trying to git gudder at making depth-based textures entirely in GIMP. It's gotten a lot easier since the 3.0 update since you can make an edit and have a stack of filters update in real time.
The background pattern is completely procedural, being a bayer matrix and maze put through a kaleidoscope, median blur, and bevel. I change the seed on the maze and get a completely different pattern.
I don't think I can go back to nodes or baking autism now.