You dont have to use them in engine. Just use them in mari to paint across textures. Back in maya select the faces based on the UDIMs and assign a shader for each tile. Move all uvs back to the 0-1 space. In case of a render engine. Lets say Arnold. The file read node does handle everything. Just select the first UDIM and…
If you have 200 uv tiles you dont have todo anything by hand. If you have a robot for a feature film with 1200 parts and 200 uv tiles you just slap one material on them and all is done. Those tiles are stored even if you go out to an other tool like zbrush or whatever. Try to preserve a per face shader assignement if you…