Revisiting that thread again. In my original post I mentioned, that I did not yet test Precomputed Visibility with these options. I now did find some issues with this.
- It looks to me like a bug, that the Force No Precomputed Lighting does also delete any existing Precomputed Visibility Cells instead of just removing existing lightmap textures.
- Also it is weird, that unchecking Allow Static Lighting does not allow to create Precomputed Visibility. While Build > Build Lighting Only is grayed out, Build > Precompute Static Visibility is still available.
I understand, that Precomputed Visibility relies on Lightmass (I assume it uses some functionality within Lightmass that does not need to be reinvented) - but I do not see any reasons, why Visibility Cells should not be working without having baked lightmaps. One is Occlusion culling related, the other purely rendering.
Some more details of what I did:
Disabled static lighting in Project Settings by unchecked “Allow Static Lighting”.
Build > Build Lighting Only is now grayed out (as expected)
Build > Precompute Static Visibility is still available - indicates, that this funcionality is meant to be available also with disabled static lighting
But using the Precompute Static Visibility function leads to
LogStaticLightingSystem: Warning: WorldSettings.bForceNoPrecomputedLighting is true, Skipping Lighting Build!
Any potentially existing Visibility Cells (r.ShowPrecomputedVisibilityCells) are deleted immediately in this case and there’s no way to recreate them.
Switch on Allow Static Lighting in Project settings again.
Now it is possible to rebuild the Visibility cells using Build > Precompute Static Visibility. This needs Force No Precomputed Lighting to be unchecked, otherwise Lightmass is completely blocked from running as with Static Lighting disabled in Project Settings and there are no cells created.
So far ok, so I have valid visibility cells and no lightmaps. No warnings in Editor Viewport. But the build complains
Lights with unbuilt interactions: 1
Primitives with unbuilt interactions: 348
Now pressing Play and getting the good old known
LIGHTING NEEDS TO BE REBUILT
OK, something not clean, but this can be fixed easily: just do a build Build > Build Lighting Only with Force No Precomputed Lighting - and lightmass runs without creating lightmaps.
But the Force No Precomputed Lighting option also deletes the Visibility Cells again. And now we run in an endless circle. Rebuild the cells needs to uncheck Force No Precomputed Lighting which in turn leads to the LIGHTING NEEDS TO BE REBUILT…
Maybe the warning does not appear in a Shipping build, but the fact, that it does appear at all makes me believe, that there’s some issue.