2022-06-01 Geometry Nodes sub-module meeting

The meeting will be open for everybody interested in joining the video call (link below).

Meeting time: 17:00 CEST (Your local time: 2022-06-01T15:00:00Z).

Links

Present:

  • Andy Goralczyk
  • Dalai Felinto
  • Erin
  • Gareth Jensen (Meta)
  • Hans Goudey
  • Jacques Lucke
  • Simon Thommes
  • Zhen Dai (Netease) (and many others)

General Discussion

  • Dalai presents feedback from watching Simon’s tutorial series.
    • The feedback mainly mainly small bugs and tasks for improvement, or miscellaneous ideas about performance and design consistency
    • Currently the realize instances node actually does always realize instances, even though there as some cases where that is unnecessary internally-- a future optimization opportunity is doing that lazily.
    • The attribute API isn’t implemented for volumes yet at all-- another future TODO.
  • Recently core geometry nodes developers (Hans and Jacques) have been working on building a new hair system for Blender. We talked about the status of that work.
    • Currently developers are still working on the bare minimum needs of the Blender studio’s “Project Heist”
    • After the basic selection tools and brushes are working, we need feedback about that core part of the pipeline.
    • There are still large unfinished parts of the system, especially on the render engine side (T96455).
  • How is the geometry nodes system and curve/hair system working for Erin in general?
    • The new curves system is a powerful tool for idealization in addition to their use in character pipelines
    • Proper support for UVs is a big missing item
    • Gizmos and interactivity are another big item
      • Specifically, gizmos that interact with the values in the node editor would be good, even simple features like choosing the transform for a “Transform” node. Erin calls back to a prototype for this behavior from last year: D9969: Geometry Nodes: Mirror node
      • There was general agreement this would be good to have.
  • Gareth wonders how the curves system works in a procedural context at this point, specifically for the guide splines / node based grooming and interpolation.
    • There are some possibilities, but because the geometry nodes team has been focused on a destructive workflow so far for the hair project, there might still be large roadblocks for procedural interaction.
    • The plan is to provide the proper building block nodes and potentially higher level nodes for common hair use cases.
  • Zhen Dai has feedback for the curve system
    • Will the old particle system be removed
      • Yes, the particle system will be replaced completely. Currently the limitation is final tools and simulation.
    • How will high level parameters be exposed so it’s familiar to users of the old particle system?
      • The idea isn’t to replace the particle system directly but to make something with a better, more flexible design

Patch Review & Decision Time

  • D14389: Geometry Nodes: Unwrap and Pack Islands Nodes
    • There was consensus that they should have “UV” in the name to make that more clear (even though there is a category).
    • Besides that, people who tested it thought they worked well. Even then, we thought some more specific testing and code review should be done to clarify what happens in some edge cases.
      • An example that was brought up: what happens when only part of a UV island is selected. Maybe the behavior is obvious, but since we’re now baking these decisions into files, we need to make sure nothing sneaks by.
  • D15042: Geometry Node: Image Info
    • Generally the ability to get this information seems helpful and reasonable on a design level.
    • The node category should be “input” like the other “Info” nodes.
    • The definition for the “Image” data-block discussed in D12827: Geometry Nodes: Add Image Texture node should be double-checked to make sure it is compatible with this information.
    • Besides that, more detailed code review can happen.
  • D15019: Instance Dimensions, Rotation and Scale Input Nodes
    • Retrieving this information from instances sounds very helpful. The “Dimensions” node should include nested instances though.
  • D15061: Geometry Node: Changing the tab of Input nodes
    • Small change, general agreement.
  • What is the general roadmap for geometry nodes?
    • Currently the focus of the core developers is getting the hair/curves system to a places where it is useful for artists, especially for the Heist project.
    • Other efforts from core developers have gone into internal refactors and performance improvements in the last few months.
    • More developers are needed to also make significant visible progress on geometry nodes at the same time.
      • Blender is looking to hire a developer to focus on this area.
    • Simulation is another big item with planned design discussions in the next two weeks while Hans and Jacques are visiting the Blender headquarters.

Help Needed

  • Currently the backlog of tasks far exceeds the time developers have to complete them. Besides code contributions, descriptions of specific workflows that currently don’t work well with geometry nodes are helpful for future planning.

Next Meeting

The next meeting will be on Wednesday 15 June, 15:00-16 CEST (Your local time: 2022-06-15T13:00:00Z), which is 2 weeks from this meeting. Again it will be open for everybody who’s interested. The provisionary meeting agenda will be linked in the #geometry-nodes channel before the meeting.

5 Likes

Any news about loop nodes? =)

2 Likes

No, not at the moment.

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I’m sorry for this questions do you have an intégration or impl"mentation for “physics / simulation / particle” nodes ?

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Yes, implementing simulations in geometry nodes is something we have in mind for the next few months. We’ll see though, some design work is still necessary.

15 Likes

I want to give this answer 10 Likes. What about hair guides? I cant image how the studio is using the new hair system without it?

Let’s try to keep this on topic, it’s not meant to be a general Q/A about planned features. Generally that sort of procedural hair/curve creation is meant to be implemented with geometry nodes.

2 Likes

Ok is a good news because such a long time so many user waiting a similar system like “Houdini” “Tyflow” or to “Bifrost” is a good news for me :slight_smile:

1 Like

Hello, I cannot attend the meeting but is there anything about dynamic nodes declaration planned in the discussion?

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i cant wait for that,thank for your job

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So, now, do I need to test correct of my node?

I’m using GN a lot for making game-ready assets, and this is a big one. The unwrap and pack tools will be amazing, but direct setting/modification of UVs will still be a big missing feature.

There are also many cases where UVs are outright cleared out, but I’m sure it’s all related.