Hi everyone, we're currently transitioning the workflow at the studio where I work to Houdini/USD with Karma. So far everything is going well, but as we continue developing, some questions about the process keep coming up.

For now, I'd like your opinions:

1. When starting a project, how do you define the USD layers for the artists to work on and populate? To prevent each artist from creating their own USD organization, do you create a master USD with the layer structure defined, and then the artists add to it? (characters, lighting, FX, etc.).

2. We will still keep animations in Maya, and consequently the rig as well. What would the USD workflow look like to send meshes to Maya, rig them, and then receive the animation back without breaking the paths inside Houdini? We tested import an alembic from animated character for example and with a sop modify blendshape them, but doesn't seems right since we have to unpack the mesh and everything.

Hi,
for question 1, i would say yes, just export an empty usd hierarchie structure file to organise your differents department.
You can use primitive to structure a manifest and then export it.
For question 2, i'm still trying to get Blend <--> Houdini usd workflow work..

I recommend that if you’re going to export from Maya and you still can’t export in USD because of the pipeline, you can do the following:

Create a file in T-pose with your character in Alembic, add shaders, and save that USD layer where you already have the material descriptions.

In Maya you have two options: export the animation in USD or Alembic, and load that animation in LOPs with:

layer_materials.usda

layer_animation.usdc — I recommend this format.

One of the important points is that if you’re using Maya for animation, you must create the asset hierarchy description—either in Maya or Houdini with custom attributes.

Example: Maya - primitve type,purpose / Houdini- variants, payload etc...

You need to create extra attributes that you can export in USD, custom primvars so you can read that data in Solaris. For example, animated texture switches, animated shader switches, etc. But that information will be provided by rig department.


If you have any other questions, don’t hesitate to send me a message.