Time

9am Pacific

Agenda

• Follow up

  • Usage of kind and purpose in video games (https://academysoftwarefdn.slack.com/archives/C03GKF4DG7K/p1673464586138349 @spiff @Kristof Minnaert @Koen Vroeijenstijn @Levi Biasco and others)

    • Adding a Purpose page in the USD Book of Remedy : who can help @Kristof Minnaert?

  • How to manage layer vs Sublayer ?

  • Removal of Boost/Python (quick shout out to @Matthew Kuruc)

• USD at GDC : when and where do a gathering?

• Difference between FBX and USD based workflows.

  • What does FBX provide that is not available in USD?

  • What might be encountered when moving from an FBX based pipeline to USD?

Zoom

https://zoom-lfx.platform.linuxfoundation.org/meeting/94179328045

Notes

USD GDC

nVidia:

• No hands on so far because of travel restriction

Gathering : @Frieder Erdmann , Rebecca, @Jeremiah Zanin 

USD : kind and purpose

Thanks @Sebastian "spiff" Grassia  for sharing the kind file from Pixar)

Remedy usage is minimal at the moment. They want to expand the filtering usage. Purpose is not very important because they don't use hydra.

Alab is really using purposes. We need to find a way to make the Pixar example legal.

Is it simple to create a new kind?

We can check @Sebastian "spiff" Grassia example.

we need to put info in the plug in info file. It is pretty simple.

Layer vs SubLayer

At Infinity War, USD is used for prototype. THe real usage is more referencing.

At SantaMonica studio, they try to figure out the USD usage, how to build scene. There will be huge transition from Maya.

At Remedy, At the begining, it was only referencing. For Geom/anim, sublayers could be a good usage.

Sublayering, source control can bring difficulties.

At Santa Monica Studio, There could be one file world file and have references from other world. They want to have layers by department. It could be nice to have overrides for Variant Sets.

Pixar : you can do more damages using sublayers. Pixar is working on namespace Edits. There could be orphrans if it is not done correctly.
THey are working on a project to avoid this:

• interaction with Source Control

• pipeline control for Orphans

• Sublayering gives the ability to work on the same subject. It was requested by a lot of people.
  Is there a lot of latency?
  One of the challenge of the namespace Edit is that it checks a lot of things.

Boost removal

@Matthew Kuruc did an incredible work.

Some time in the near future, USD will be compiling without the usage of Boost except  for Python.

They are approaching the removal concept by concept.

What about the other dependencies? Is ther a huge usage of Boost?

• Move away from TBB for core

• MaterialX have no external dependencies

• every library that uses Boost should be reached out and explained that they shouldn't use boost.

• TBB:

  • creation of an abstraction (Work) to be able to use every own scheduler.

  • Pixar is making the work management abstraction to be plugable.

For Remedy, the real issue is Boost Python.

For Santa Monica Studio: USD is in the tool so there is no real issue. 
The TBB abstraction would be nice as they are using their own scheduler.

At EPIC, they use Boost for the Editor.

The final removing of Boost is also moving to C++17

USD vs FBX

The real question is why FBX is still an option?

@Dhruv Govil explained that there a lot of things that are working well in FBX :

• IK

• COnstraints

• Animation curves

• Takes

  • Takes are similar to a Variant. You can blend between takes. They are libraries of animations. You can feed them to an animaiton Blender.

You want to be able to use several variant at the same time.

Does USDSkeletalAnim serve this purpose?
Yes it could.

Usage of Animaiton Blender will introduce complexity in the pipeline and it won't be as powerful as Houdini's ones0.

It would be great to have the ability to link a skel to a group of animation.

A colleciton could be the way to go.

For unsampled curves, we could use AnimX.

Attendance