2023-10-09 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: October 16, 2023, 11:30 AM to 12:00 PM Amsterdam Time (Your local time: 2023-10-16T09:30:00Z2023-10-16T10:00:00Z)


  • Clement
  • Jeroen
  • Michael
  • Miguel

Blender 4.0


  • Refactor lighting evaluation to experiment with different shadow compositing. SSS Translucency Evaluation is extracted outside the light loop for better light evaluation.
  • Some experiments are being done how to handle geometry thickness related to different effects.
  • Development of planar reflection probes started. Still needs to be included into the raytrace pipeline.
  • Test support is merged in main. Will help on finding regressions and artifacts on platforms. [#112161 - EEVEE-Next: Tests support - blender - Blender Projects]


  • During the meeting discussed how to handle SSBO read-back barriers. In the Metal backend a GPU_finish has been removed for performance reasons, that breaks test cases. We discussed about having a dedicated API for syncing between the host and device buffer. A PR will be sent in to discuss the API in more detail.


  • Initial Wayland swapchain has landed. Wayland clients don’t have the concept of a window and the client itself is responsible. For OpenGL there is a library used wl_egl to keep track of the window state, but it is connected to the EGL library. For Vulkan there isn’t a similar library provided. Currently Blender keeps track of the window size and the needed size for the swap chain. The performance isn’t where we want it to be. In the future we need to address this by looking into specific vulkan extensions like VK_EXT_swapchain_maintenance1.
  • Vulkan is enabled as eperimental options in main. This means that every alpha build of Blender 4.1 will have an command line option to start Blender using the Vulkan backend. This is highly experimental. More information can be found in this post.

I’m testing EEVEE Next on Metal, and the only light type that works for me is Sun, or World lighting. Is this expected for now?

That can be. We had rushed the latest changes, knowing we broke stuff. Give us a bit of time to stabilize, otherwise everyone will report the same issue.

Thanks for testing!