Is there a reason why some meshes are just not effected by occlusion culling? When looking at this part of the level, you can see meshes being occluded past the walls of the hallway.
But in this second picture, looking at the same hallway, the walls of that hallway aren’t being occluded even though I’m looking at it from behind a wall of another room.
I’ve already checked that they are in fact being rendered via the freeze rendering command. They do get culled through the view frustrum though, so it’s not like they’re immune to culling as a whole
And I’ve already gone over all the mesh settings, comparing them to meshes that do get culled, and nothing I change works
Occlusion Culling is turned on in the settings
The meshes bounds are not oversized
They aren’t a generated mesh from a blueprints construction script or attached to any blueprint in general
I’ve also tried using commands like r.AllowOcclusionQueries=1 and r.InstanceCulling.OcclusionQueries=1
Any help is greatly appreciated, as I can’t help but feel like it’s a simple solution that I’m just not seeing or understanding.
To add on to @zeaf’s suggestion, are they instanced meshes? Instances in Unreal really struggle to define cluster bounds and often have trouble occlusion culling.
Hmm yeah that’s very odd. I’m going to keep an eye out on my end for this issue and if I find it, I’ll try to find a solution.
Since I can’t currently replicate it on my end, this is a tough problem to help solve, as it’s definitely not expected behavior. My one suggestion is to check that “Use as Occluder” is turned on for your blocking mesh, though admittedly I see no reason this would be turned off. You could also try turning off Hierarchical Z-Buffer Occlusion if that’s enabled (with r.HZBOcclusion=0), since this culling method isn’t as accurate.
That being said, it seems that other people have had this issue too
Unfortunately, it seems like no one there had much luck either. You could try using Precomputed Visibility Volumes if you’re on 5.2 or lower, or use one of the suggested plugins to try restoring UE4’s Software Occlusion Culling.
Given the amount of complaints I’ve seen about this and similar issues, I’m going to see if I can raise it as a concern to Epic for some more in-depth documentation. Good luck with this! I’ll keep an eye out for anything else that might help.
Thanks for the suggestions, but none of that seems to work and unfortunately I’m on 5.4. And yeah I had already found that thread but their issue seemed to be a little more broad than mine. Especially since doing some further testing, it seems new meshes I’m pulling in from the content browser ARE being culled properly. Even though they’re the exact same SM as the others.
So i’m not sure where the problem stems from but it appears that only meshes that had been alt+drag copied had the culling issues. Although when alt+drag copying these new ones I’m pulling from the browser, they cull just fine too. So I’m not sure if it had something to do with pasting meshes into new sublevels, or the original meshes I had placed had something wrong with them. I’m just going to replace all the geometry I can for now and if I discover any further issues I’ll come back and mention it.
