Quick answer: Don’t flag moving objects as Occludee Static — the baked data assumes they never move. Tune Smallest Occluder, and rebake after level geometry changes.
A level uses baked Occlusion Culling. A moving platform vanishes when it travels — it was marked Occludee Static, so the bake culls it based on its original position.
Static Flags
Occlusion culling baking only applies to objects flagged in the Static dropdown:
- Occluder Static: this object blocks view of others. Must not move.
- Occludee Static: this object can be culled. Must not move.
Moving objects: clear both flags. Unity then culls them with regular frustum culling, which tracks their actual position.
Smallest Occluder
In the Occlusion window → Bake tab. Smallest Occluder is the size threshold for an object to block view. Too small = noisy data and over-culling. Default ~5m; raise for cleaner results.
Backface Threshold
Lower it if thin walls aren’t occluding. Higher if you see false positives. 100 is the safe default.
Rebake After Geometry Changes
Occlusion data is baked. Moving a wall, adding a building, resizing the level — all invalidate the bake. Rebake or you cull against stale geometry.
Verifying
Moving platforms stay visible throughout their path. Static geometry still culls correctly behind walls. Occlusion view mode shows expected culling.
“Baked occlusion assumes nothing moves. Clear static flags on anything that does.”
For largely-static levels with a few movers, baked occlusion is great. For highly dynamic scenes, consider GPU-driven occlusion instead.