Lumen GI with SkyLight on planar surface cause grid like artifacts.

How can I get rid of the grid like shadow artifacts on the ground? They seem to be caused by Lumens GI when I add a SkyLight to the scene, and are most visible on flat surfaces.

They would probably be less visible in a complex scene, yet on a flat surface it stands out. It also fades away at a certain distance.

It’s seems like a resolution or quality setting, however I had no luck so far in finding the right parameter.

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Luoshuang recently made a commit to the github repo that resolves this issue, not sure if it will make it into 5.1.1 but it should be fixed at some point. If you need a fix urgently I recommend building the ue5-main branch from source.

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Amazing, thanks!

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I was digging for the same thing but didn’t want to mess with creating a fork to the UE mani branch just for this. I finally found the setting wich seems to work without any noticeable defects…

r.Lumen.ScreenProbeGather.RadianceCache 0

cheers!

The link is not working, can you send it again?
I’ve been having the same problem for months and I can’t solve it, if you can tell me what the solution is, I’ll be extremely grateful.

The link works, you need to be logged into github, and link your github account to your epic account in order to see the repo.

This isn’t going to be much help to you though unless you build the engine from source. Your best option is to simply wait for 5.2 or whenever it gets added to the engine.

I found reducing cubemap resolution to 8 in the skylight fixes the issue as well