[Bf-usd] Welcome to the BF-usd mailing list

[Jan Walter]

Hi,

Maybe as a start of a discussion, how the Blender integration could look 
like ...

 > How do others (e.g. Houdini developers) approach the problem?

Here is a short article I wrote about the Houdini integration:

https://www.janwalter.org/jekyll/houdini/rendering/solaris/2020/12/10/houdini-indie-solaris.html

It links to several videos from Jeff Wagner and Varomix Wey.

Jeff's videos are a bit older and talk about Solaris and RenderMan 23.2.

Varomix talks about any renderer designed to work as a Hydra delegate - 
renderers such as Pixar's RenderMan, Autodesk's Arnold, and Maxon's 
Redshift.

I also made a video showing the Cornell Box in Houdini Indie, setup for 
three render delegates, Karma, RenderMan 23.5, and Arnold:

https://youtu.be/sKX5qU1APyk

Top left is Houdini's viewport, switching renderers is like in usdview,

select the render delegate and it takes over the viewport.

Lower left is basically how the USD outliner would look like.

I assume that this reflects how an exported USD file would be structured.

Lower right is the Solaris context (stage) network. Basically you bring 
in geometry (e.g. as .obj files), add for each piece of geometry a 
material library (in this case a common material to refer to, which 
defines for each renderer a render specific material). Cameras and 
lights need to be defined in the same network. All other nodes just 
influence the way the USD file gets structured. This workflow is very 
specific to Houdini.

Any ideas how that could look like in the current Blender user interface?

I assume the switch for the renderers is already there. Most renderer 
specific addons use that switch already. Maybe the node tree for 
material/shader nodes could have an abstract USD material, which other 
3rd party renderers could plug their specific nodes into? Cycles could 
be the default or just one of the nodes being connected to such an 
abstract material. I will provide a screenshot of how this looks in 
Houdini at some point ...

Jan