Initial implementation: D12871: Cycles: Light Groups
Improvements (color indicates estimate for difficulty):
- D14540: Cycles/UI: Support adding Lightgroups from the object/world properties
- D14740: Render: Update lightgroup membership in objects and world if lightgroup is renamed
- D14596: Render: Add operators to add all used or remove all unused lightgroups to a view layer
- Support setting lightgroup on a per-collection basis
- Support viewing Lightgroup passes in the viewport
- Support denoising Lightgroup passes
- Support splitting the sun and sky parts of the Nishita Sky model between groups
- Support having different environment lighting in each lightgroup