2023-07-17 Eevee/Viewport Module Meeting

Practical Info

This is a weekly video chat meeting for planning and discussion of Blender Eevee/viewport module development. Any contributor (developer, UI/UX designer, writer, …) working on Eevee/viewport in Blender is welcome to join.

For users and other interested parties, we ask to read the meeting notes instead so that the meeting can remain focused.

  • Google Meet
  • Next Meeting: July 24, 2023, 11:30 AM to 12:00 PM Amsterdam Time (Your local time: 2023-07-24T09:30:00Z2023-07-24T10:00:00Z)

Attendees:

  • Clement
  • Jeroen
  • Michael
  • Miguel
  • Brecht
  • Francesco

Eevee-next

  • Light probes landed in main. Light probes are now updated on the fly and during image rendering are updated for each frame. Current design only supports spherical probes and most options have been removed. When they still have value they will be brought back.
  • Point clouds support landed.
  • SSR denoising patch added for review.

During the meeting we went over the current state of Eevee-next to find our the feasibility of having this in Blender 4.0. We think that most of the features can be implemented over the next few weeks. At that time we will also communicate via devtalk to start testing. We expect that it can lead to many bugs that we are not aware of, due to Eevee-next isn’t tested due to missing or changing features.

Currently we know of compatibility issues with Intel GPUs (both iGPU and discrete) and specific AMD platforms.

It hasn’t been decided if it all fits in the schedule as due to these unknowns. When we have more insight on stability (platform + functionality) we will make a final decision if it will be a 4.0 or 4.1 target. It is
better to have a stable system than something that will not be received well. Eevee is to important for Blender.

Major Topics:

  • Irradiance Volumes: Much polish to be done to make it fully usable. Still needs design related to scalability.
  • Reflection Probes: Working (more or less), but would need a good solution for alpha blended objects that cannot do raytrace (revert to FIS).
  • Soft Shadows: A bit of an unknown as we need to trace the shadow heightfield and this has some implication with the Virtual Shadow Maps.

Small Issues:

  • Volumetrics Shadow Support: Needs to wait for shadows to be finished as this would require shadow tracing. But can be enabled before that even.
  • Object ray/bake visibility: This is needed to replace reflection probe Visibility Collection.
  • Bent Normals: Ambient Occlusion needs to be integrated into Irradiance cache sampling to give correct occlusion.
  • Contact Shadows: Needs to know how much distance to trace (instead of relying on user param). Otherwise, easy to port.
  • Overscan: Architecture is there to support it (in viewport & render). It’s just a matter to implement it.

Compatibility support

  • Curves on Metal: This was fixed at a higher level. The PR just need a few adjustments.
  • EEVEE-Next Shadows on Metal: Some out of bounds reads issues are left but otherwise good progress with workaround renders.

UX / Polish:

  • Screen Tracing & Denoising : Still needs UI polishing.
  • Material Settings: Blend modes needs to be revisited because opaque changed behavior (it can be transparent).

Delayed features:

  • Volumetric temporal stability: Can be postponed, but would be nice target considering that EEVEE-Next is aimed to be temporally stable.
  • Reflection Planes: Not planned for initial version. Might be considered a regression. But design of how to integrate them into the deferred tracing is up to discussion.
17 Likes

do I understand correctly that now don’t have to come up with a way to make eevee bake the light on each frame?

Yes, we might want to add a baking option on top of it. The baking option would be for complex scenes (much geometry) or when dealing with many reflection probes.

Another note would be that the viewport reflection probe is currently only updated when the probe itself is modified. We could eventually also add options (not decided yet) that will also update the probes on other trigger points. For now we didn’t add those as it also impacts the playback of animations.

6 Likes