Hi Every body i Have a weird Artifact around some foliage when i am rendering and in real time its ok i am on Unreal5.1 is there some body have any clue where its coming from ?
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Hi @phudon
Whats the artifact you mean? I dont see any issue or am i wrong?
Check the image i high lite in red you can see the line on the reflexion on the water under the Foliage
oh they kinda look like the reflection of a city skyline?
Looks like something is getting a bad reflection, try hiding just the trees and check, if not try the mountains, it is weird tho
This looks like typical screen space reflection artifacts. Lumen uses a combination of screen traces and raytracing, so SSR artifacts may still be exhibited in some cases.
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Epic actually just posted a blog post about the Lumen team’s work on Fortnite and this was mentioned in it:
On the topic of water reflections, we had vertical streaking artifacts wherever Lumen’s screen traces were interrupted by a foreground object. This was incredibly distracting for a character in motion. Lumen’s screen traces don’t know how thick an object is, so we have to switch to software ray tracing for the rest of the ray, which often produces a different color. This was a regression over even Screen Space Reflections, which used a much cheaper but less accurate method of intersecting rays, but allowed continuing behind foreground objects. We were able to solve the vertical streaks by sampling the screen color even for software ray tracing hits, which reduces the mismatch. This one came in at the absolute last minute so it was not part of the UE 5.1 release.
So I expect it will be improved in either 5.1.1 or 5.2
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