SSGI is worse in unreal 5?

Development Rendering
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I was wondering, has anyone else noticed SSGI is now worse in unreal 5?

SSGI worked pretty well in unreal 4. It produced decent lighting for lower end machines.

In Unreal 5.4, the SSGI is now noisier and more pixelated. It appears to be stuck as halfres.

I noticed there are now fewer SSGI settings/SSGI console variables. Also some variables are bugged, or just don’t work. For example in ue4 I would do r.SSGI.LeakFreeReprojection 0 to save some performance. In ue5, this now makes ssgi disappear altogether.

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Here is an image comparison:

ssgi issue
ssgi issue1711×719 54.7 KB

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Given no-one has responded to this thread, I can only assume this issue doesn’t affect many people. Im curious as to why though. Is it because no-one uses SSGI? Or because people aren’t familiar with how it was in ue4?

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Personally I only rarely use SSGI but I have noticed this. It’s visibly downgraded since UE4 and I’ve never really been able to get it to improve much.

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This issue still persists in unreal 5.5.
Im not sure why epic would ruin a perfectly good feature like this, but my guess is they altered this effect to look and perform better when used in conjunction with lumen, dfao, and upscaling, disregarding how it looks in standalone use cases.

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I compared 4 and 5 versions and its looks like unreal 5 have enabled r.SSGI.HalfRes 1 option and in 4 you can not use it so it looks much better

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Indeed. I found a way to get full resolution ssgi. You can use the command: r.DiffuseIndirect.HalfRes 0

However I am still missing the ability to disable leakFree Projection (which was a much needed optimization). Also I am missing the ability boost the ssgi illumination in ue5.

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thanks for sharing that! it looks better now, a bit grain but better

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yeh… ssgi is not very good in the first place. lots of offscreen and angular occlusion artefacts.

i’d like a somewhat cheaty solution for my prototype tho. 3rd person flashlight in a baked environment. ndgi.

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Quality-wise yeah its not great. Performance-wise, its excellent. Or it was in ue4 anyway.

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