I have a somewhat unique case for OLT integration into Unity in that I'm going to be applying materials at run-time based on a preexisting material atlas. I don't necessarily need the material IDs output with the OTL to be anything specific, just that they're unique and correspond with the materials applied in Houdini.

I can't seem to figure out how to get this data exposed to HoudiniPartControl.prMaterialId, though. Any help would be appreciated.

(ended up solving this by just grouping together various parts of the mesh and assigning them as one field in a multi-material node).

Ya, I can't think of good way to do that at the moment. Not sure I fully understand your workaround but if it works for you then great!

There's future work planned that should make this easier but I can't promise any dates at this time.