Hmmm, turns out it’s not quite what I am after, sorry. Basically, what I am dealing with is a kind of homebrew vegetation system, so it does need to be per instance - I want to spawn a load of instanced meshes, with randomized textures based on a subUV atlas, sort of like you would with grass (the system we’re using has some expanded functionality that basic vegetation doesn’t offer, hence we’re making it ourselves). Basically, I want exactly the kind of random subUV thing I can do in Cascade where a random sub-image is chosen for a given particle, except I want to do it inside the material. In a nutshell, I want a material that says “My atlas has two rows, two columns. Choose and display a random image from that.”