Importing meshes from max with multi sub into houdini - any way to assign a multi map without the unpack node?

[joconnell]

Heya Folks!

I'm bringing a max environment across into houdini vray as we have to integrate with fx. It's pretty dense with a lot of different models to start off with and those models are all using a multi sub of about 50 materials across the lot. It's fine to bring in some meshes and use the unpack node to access groups for material assignment but as the model count grows it's not going to be a viable workflow in terms of viewport speed. Is there any type of mesh that can be brought into houdini and vray can assign that multi material directly and render correctly with no other nodes? Or is there another workflow I'm missing out on that could achieve something similar? It maybe makes sense to do a vrscene per object since I could probably maxscript that but it'd be great to go with something like alembic where our other departments could use the same files.

Cheers for any thoughts!

[glacierise]

You can use the pattern id node to define a condition that picks a multimap input. Attributes in the expression - assuming you use packed alembics you can access any integer, float or vector, and the 'name' string attribute INSIDE the packed alembic - no arbitrarily named string attribute. For attributes in outside the packed, you can use any

[joconnell]

Gotcha, so I'll have to make sure any of our face sets are either made into an integer or put specifically onto that name string attribute - more on our alembic export pipeline side / routing of data so? Have you gone 100% houdini on your side or are you occasionally feeding some max stuff over also?

Cheers for the info!

[glacierise]

100% Houdini since the end of 2019, it's been wild but it's awesome

[glacierise]

Geometry management wise - when you build a detailed enough name hierarchy, like /house/windows/glass/front/010 then you can do expressions like *windows*glass*front* as patterns that are very useful. The alternatives are to assign integer attribute values, like the material id in max, that signify some groupings, or to pack accordingly and assign shaders to the packed, but that's quite limiting.

[joconnell]

Super - quite like clarisse's rules in that case, I'll change my way of thinking about it. Much appreciated Hristo!