Ray Traced Shadows Artifact [UE 5.4]

Hi, recently, with the 5.4 update, I’ve noticed a weird artifact in some of my levels when Cast Ray Traced Shadows is enabled on lights. I’m getting a weird scene duplicating, where my lights will fully disappear and reappear, or as an overlay of everywhere lit by ray tracing will move around my viewport. I’ve only noticed this in 5.4 since they fully removed RT. I’m not sure if I’m doing something else wrong since I was used to fully ray-traced scenes, and I wasn’t a lumen user. So, if this is a bug on my side, I would love some help.

You can see parts of the scene are duplicated and moved [two of the mannequins]

It’s like his light sometimes moves off of him, and other props move around.

[VIDEO showing RT Shadows on and OFF]

1 Like

Got exactly the same problem, if I have ray traced shadows enabled and I rescale my viewport this happens:

It works fine after restarting the editor, but whenever I resize any ui element that interacts with the viewport OR I open material editor, it breaks again.

Ray Traced shadows are mych better for visualisation, smoother, more detaild, this breaks my whole workflow now.

Edit: After fifth or sixth restart it stopped happening. It’s fine now.
This is some chaotic behaviour, what the hell?

1 Like

Hi, I’m experiencing the same issue, and restarting the project isn’t helping.

@BananableOffense Please provide a solution. Every project in my library is behaving this way, and I don’t know what to do.

I believe this is a driver issue, try rolling back your GPU drivers to a previous version.

Ill have to try that I just had an update the other day which didn’t solve anything I can try downgrade

Looks like it mightve been fixed in the latest Driver update

1 Like

i have rtx 4080 and latest nvidia drivers, the problem hasn’t gone away (.

im facing the same issue but in 5.2 version
srsly epic doesn’t know this bug at all? and how can very few people are facing this???

Hi all, I encountered this problem in UE 5.4.4 and I managed to partially fix this problem by disabling Virtual shadow map and activating Shadow map, mine the problem itself seemed very significant and in order not to risk it, I still decided to create my own project on UE 5.3.2

This is a nvidia drivers issue. You need to roll back. I don’t know the exact one but tru 552.22 and see if it solves you issue to be sure its drivers.

I was able to fix this issue by enabling Substrate Materials in the Project Settings