[UE 5.4] Weird shadows jittering / flickering despite of distance

Development Rendering
1

Hello,

I’m facing an issue that I can’t resolve, despite all I could read of this forum and others.

My project is under Unreal 5.4, and I don’t know why but shadows on some buildings, and on the road are jittering / flickering :

I’m not using Lumen (as far as I know), my ScreenPercentage is at 100%, I’m using stationary directional light with baked lights (tried a lot of different settings I saw on this forum), virtual textures, etc …

I also tried new plugin GPU Lightmass to build lights, it does the same as CPU lights building.

And finally, I tried to activate Lumen GI on my Post Process Volume, and it does the same too.

I’m a bit confused, I saw many other people facing similar issues, but it seems like a few get a solution :frowning_with_open_mouth:

Thanks for your help :pray:

2

Hello everyone,

I still have this problem 2 weeks later, tried different solutions I saw here but nothing change :frowning:

I’m not even sure what is exactly cause this issue.

If anyone got a potential solution, I will really glad to hear it !

Thank you

3

This looks like an AA/TSR Issue. Might be a good place to start

The r.TSR.Visualize console commands are very useful for debugging.

4

Hello !

Thanks men, indeed it’s a TSR issue, we could visualize well with your command.
(And btw, thanks for the docs, it’s very interesting)

You can see on this following video :

We upgrade some of our meshes, but some are still causing issues like you can see (like poles, or windows).

According to you, what should we you to minimize this effect ? Is this issue mainly related to our meshes, and/or an issue relating to view/draw distance ?

5

In my experience the most impactful change for this type of issue is the balance between native viewport resolution, and final TSR Screen Percentage. When trying to upscale from a lower resolution to higher TSR output, the larger the upscale the more potential for issues around improper optimization and flicker period miss alignment.

But pretty much anything I could suggest is pretty extensively covered in that documentation posted above.