Is this the occlusion culling Roblox talked about at RDC?
Yes, it’s available on Studio as 2 fastflags (MaximumADHD found them):
FFlag EnableVisBugChecks27 : true
DFFlag UseVisBugChecks : true
And you should know the old adage of ‘at your own risk’ by now… 
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I have no idea how to enable FFlags, is that a file on my PC?
If that’s the case you shouldn’t really mess around with fastflags; everyone likes to say that changing them will summon some sort of crystal shaman that will corrupt your saves, and I have no doubt that it can and will happen, so please, really, unless you want to wake up one morning to a baseplate, I’d advise against venturing into the unknown that is fastflags.
Fine with the risk? Get MaximumADHD’s Roblox Studio Mod Manager here. Install Studio and override the 2 fastflags as mentioned above.
Again, please heed the warning as even Roblox themselves don’t like it when you do stuff.
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This feature is added as a fastflag for now i guess and it’s a pretty big leap forward. But what I don’t like is that it doesn’t cull terrain, which is also pretty important (in my use, I’m not saying a big word for everyone, but this would be a nice thing to have)
i think that it will cull objects that are hidden and not triangles that are hidden because checking for every triangle might make a performance loss even worse than without using occlusion culling ( I may be wrong )
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You seem to be right. Best way I have found to check this out is in Wireframe View.
Very interesting to play around with.
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Hm, seems a bit buggy rn, but hopefully that’s fixed in the future!
I don’t think it’s that buggy. It looks like a few things are just missing here and there and the culling is trying to be conservative - one of the things about occlusion culling, well really any culling, is that you’re not actually meant to notice it in action unless you look at the scene tricount.
As for the terrain - yes it sucks, but I don’t think even Roblox themselves can figure out how to deal with the terrain since you can’t just nil parts of it and put them back like you would with any other instance. That alone should be a deal-breaker if you want to use terrain for a serious open-world game because it’s 2 tri’s per 1 voxel which is just cruel for any system if used extensively.
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This isn’t what I had in mind in regards to occlusion culling. I thought that meant the engine wouldn’t render parts which weren’t in the camera’s view, but it seems to do the opposite.
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Not exactly sure what type of occlusion culling they use (don’t think they’ve shared it yet), but it doesn’t seem to cull objects on the edges of the frustum for some reason. Unless you meant frustum culling, which I believe they already do that; but maybe the two are conflicting object culling?
Although, this doesn’t happen at a lower FOV for some reason…?
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that is called Frustum culling it already exist in the Roblox’s rendering engine from a long time
what they will add is occlusion culling which will not render objects that are blocked by another objects
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It looks like the culling system is only checking for objects in a smaller FOV than the camera. The culling’s FOV is probably made to dynamically expand or shrink depending on how much choochoo power is in the Galaxy S3 that little Ethan has. Which I think is a bit of a stretch but it could be cool.
Look - I suggest that we shouldn’t really dog on the occlusion culling that much while knowing pretty well that it’s not meant to be a production-level feature yet. Remember when the GTA 6 leaks happened and everyone started throwing crap at Rockstar just because it looked horrible, despite the footage being that of an early development stage? This is kinda like that…
Whatever meanie words you have in mind should be saved for if these issues make it through to little Ethan and his prehistoric rotary phone.
I don’t really use “meanie words”. I stopped doing that a while ago.
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this is most likely just the occlusion culling’s FOV being smaller than the frustum culling’s FOV. those objects are definitely getting culled once they go offscreen since the engine already does that, no need to do extra calculations on objects that are already culled
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Why not make it only an option for pc roblox games. I think Roblox really needs better performance and more graphics customizability. This could be the first step to making Roblox have better performance, even if only on pc.
I did not realise that. Thank you.
The 10 year wait was totally worth it
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