2022-09-08 Pipeline, Assets & I/O Meeting

Everyone is welcome on the Google Meet linked below every other Thursday, at 17:00 CEST.

Present: Bastien Montagne, Bogdan Nagirniak, Brecht Van Lommel, Brian Savery, Charles Wardlaw, David Feltell, Georgiy Markelov, Julian Eisel, Michael Kowalski, Sonny Campbell, Soslan Guchmazov, Tom Cowland

The meeting covers the pipeline & I/O module in a broader sense, including some topics hosted in other modules (e.g. some I/O python add-ons, or overrides and .blend file I/O from the Core module).


Collections for Import/Export Design & USD

Charles joined nvidia last week, he will work with Michael on USD.

Bogdan and Georgiy are currently employed by AMD to work with Brian on USD projects.

Michael has been working on supporting blend shapes, and some material IO fixes.

Bogdan and Brian think that the Hydra render engine add-on is already fairly usable and testable. It may soon be merged in the main USD development branch to help getting more people to test it. It requires some different build of the USD library though, which are still being worked on for Blender 3.4, or maybe rather 3.5 (due to complex changes of moving some of our libraries to dynamic linking, and aligning to OpenVFX 2023 for 3.5).

Brian, Sonny and Michael had a meeting last week to align further on a common design.

The ‘simple’ case of the Collection I/O project, adding import/export features to Collections in Blender, while still keeping all data manipulation in Blender area, is being owrked on by Sonny.

There was a long discussion over the ‘complex’ case of handling USD data (i.e. not simple import/export, but rather editing/authoring of USD data itself in Blender), with many open questions:

  • Do we need a special type of collections, or can we rather work with ‘compositing’ nodetree attached to a regular collection?
    • Would such a collection authoring tree only affect I/O, or should it be also actual part of Blender scene evaluation?
  • How can current Blender collection/collection instanciation system work with USD ‘collections’, e.g. when it comes to transformations? Do we need some neew type of data, ‘group of objects’?
  • Can we use a ‘simple’ layer-based UI/UX in the outliner for authoring of USD?

There is need more concrete plans and/or prototypes to better understand where to go, and what are exactly the issues that need to be fixed here.

Assets & Asset Browser

  • Updates following the discussions at siggraph regarding OpenAssetIO.

    • Tom Cowland and David Feltell joined the meeting to represent the OpenAssetIO working group.
    • There is general agreement from the Blender team that OpenAssetIO would be good to support in Blender. How exactly is to be defined still.
    • Julian checked with the Blender Studio if they are interested in supporting OpenAssetIO for their pipeline tools as well. Generally they are interested in it and would like to investigate it further, but it’s not a priority right now.
    • Communication between the OpenAssetIO working group and the Blender developers should stay active for the benefit of both. Blender developers are also planning to join some of the OpenAssetIO meetings.
  • There was not much focused Asset Browser and Asset System development recently because of other priorities. But the Blender Institute is starting a brush asset project as the next use case to push new asset workflows further. Plus, the geometry nodes team is making node group assets part of the general node workflow, by integrating them with as if they were bundled nodes in Blender.

  • Julian has been doing some design work to introduce the concept of traits, as a way to define type information for assets that can then be mapped to expected behavior. OpenAssetIO has a very similar concept so the designs are well aligned.

Next Meeting

The next meeting will be on Thursday 22nd September, 17:00 CEST/Amsterdam time (your local time: 2022-09-22T15:00:00Z).

The provisional meeting agenda will be linked in the #pipeline-assets-io-module channel before the meeting.