ill check that and thanks for replying
Looks like the Unreal Engine 5 Early Access 2 Hotfix has mostly fixed the issues of unstable pulsating GI / Reflections. I almost don’t get that bug anymore (still happens but greatly reduced and not as glaring as before), with any type of lights. I have a lot of highly reflective surfaces in my test scene, maybe that’s why. Anyone can confirm this? I did not find anything in the release notes that talked about this, but glad that it’s (almost entirely) fixed.
I’m curious about this. Single Layer Water also didn’t support reflection captures in UE4 (only skylight reflection) so I suspect it’s all part of Single Layer Water still not being on par feature-wise.
I hope this gets addressed, water is so much more than an ocean reflecting the sky
I seem to be getting huge amounts of noise in my UE5 scene using Lumen - does anyone the best method to remove this?
Thanks Piers
Uploading: noise Capture 02.JPG…
The issues described in Post 48 (Lumen GI and Reflections feedback thread - #48 by Yaeko) are still there in EA2, no improvement at all.
Hope this gets fixed soon, given how often I have seen this issue on the forums now.
Thanks for UE5. I use Unreal Engine since 1999 and this is the best dev experience ever!
I have 3 little clips showing weird lighting behaviour depending the camera’s distance to a mesh.
The meshes don’t always seem to block off lighting.
This is basically a giant room with a sun lightsource outside.
Putting a light in this bottle cap, it only behaves correctly when you’re close, and becomes weird as you get further away:
I also just hit a very important issue for our project. We’re building a miniature world and we build everything at 10x scale. Problem is, when the sunlight enters the room it doesn’t bounce far enough to light anything. So the room is basically dark besides the first bounce locations.
Is there or will there be a way to adjust the lumen-scaling?
It would be painful to build everything at real scale for what we do.
Here a demonstration of what I mean; first a normal size room and then our 10x sized room that’s dark:
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Look at the Large Worlds section.
I came upon the same problem. Creating a miniature world with lumen is hard. But the distance fields are O(n^3) and it’s essentially the “teapod in a stadium” problem. I do not assume that they will switch to a more sparse representation or that it is even feasible.
However, having a global scaling parameter for lumen would be great.
**Edit : Seems to be a level specific issue **
There’s a large update regarding mesh cards representation generation available on ue5-main, so far it seems to have partially broken GI for me (diffuse color not being taken into account or whatever is happening, see pictures below).
Noticed something else with Lumen that isnt working (in EA2).
Point light length isnt taken into consideration for Bounces it seems.
As can be seen in this image, only the actual position of the light contributes to GI, not the “ends” of it, allthough the light clearly is visible on the floor.
I’m getting quite a lot of flickering when the camera is close to walls or is at an angle to direct light.
Has anyone else encountered this or know if there are console commands I could try? It doesn’t seem to be a screen space problem as it still happens when I have screen traces and screen space reflections turned off.
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This one is known and has been improved in latest UE5 Main branch.
We do make a lot of assumptions about scale being around human height and human sized buildings. For trace distance you can set r.Lumen.MaxTraceDistance, that one is easy. But there’s the Voxel Clipmap size, the Global SDF size, the Radiance Cache clipmap extent, the r.Lumen.DiffuseIndirect.MaxMeshSDFTraceDistance, it goes on and on. All of those scale dependent values should be exposed in cvars under r.LumenScene or r.Lumen. If you can find them all, you might be able to make it work.
Hi Maxime, could you share this broken geometry / scene, so I can investigate and fix it?
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Hi Yaeko, those are definitely bugs in Lumen. Could you send me your scene and exact repro steps? I don’t think we’ll have time to investigate for a few months but I’d like to make sure it’s fixed for 5.0 release.
We have fixed a few bugs in packaged builds in UE5/Main since Early Access was released.
Hi Yaeko, I tried to set this up today but wasn’t able to get the same results. I placed a Point Light, changed to Movable, set AttenuationRadius to 10k, SourceLength to 6k. Lumen still bounced lighting from the entire length, and I could see in Show->Visualize->LumenScene that the shape of the light’s direct lighting matched the main view. What are the settings on your light? Check that your Lumen Scene is not black anywhere, when you put a light near it. That means the Surface Cache generation failed, probably because of not separating meshes:
That doesn’t look like Lumen GI or Reflections artifacts. Those look like noise from one of the deprecated Ray Tracing features. Check your PPVolume (if you have one) or project settings. Dynamic Global Illumination Method should be set to Lumen, and Reflection Method set to Lumen.
Lumen Reflections not yet supported on Single Layer water, hopefully for 5.0 release or later.
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