Im a beginner and would like to know if its possible to get rid of these artifacts caused by Lumen. They appear while walking and turning fast.
Lumen unfortunately works with accumulated lighting info with extra information from screen space. When you turn the corner the scene changes are so dramatic that it takes a while for the samples to update.
You can try changing the lumen update speed via a post processing volume:
If there aren’t any dynamic lighting changes in the back rooms then maybe baked lighting would be an alternative.
Thanks for your tip, but when I put both scene and gather lightning update speed on the max setting, I didnt notice any improvement. I played around with baked lightning for like half a month and never got any good result, so I will definitely keep working with dynamic. Isnt there a way to make the screen where Lumen renders the scene a bit bigger so it will be all loaded when my camera gets there?
There is, they made use of a method like that in Valley Of The Ancients to avoid accumulation issues when swapping worlds, but I don’t remember what it was- I would suggest you check out their method for inspiration?
making the screen bigger won’t help much if lighting moved into previously occluded spaces.
@jblackwell scene capture with a postprocess crossfade until the real world is lit correctly? i dunno tho. i never ran the demo.
This made it maybe little bit better, but still did not solve the problem. I also just noticed that in some parts of the scene the light is not calculated. For example on the left wall in the bottom left part
Could you please explain me how to do it?
My problem has been partially solved, but it made my previous problem appear again. I had an invisible white floor above the main floor that made the light bounce more onto the ceiling and make it look lighter. Now the artifacts are gone after deleting it but the ceiling is totally dark, which I dont really want
In the post processing volume:
You can use the skylight leaking to inject skylight values into your lumen scene to boost the lighting.
The color boost can also increase the lighting values.
Just set the extent on your post processing to unbound.
But you do need a skylight in the scene to be able to boost the values. So you would need it around your rooms.
Out of curiosity, are you using TSR or something similar? Sometimes artifacts that appear to be lumen are actually the product of the upscaler overall, or even stranger things like the volumetric fog froxel buffer if you’re using VFog.
Honestly speaking, I think you may want to give baked lighting a try again, especially given that most of your materials look near-diffuse. The lumen problem with your scene setup is that it’s pretty much designed to cause constant disocclusion, and since that’s a problem with the screen-space gather, you can’t really do much more than flush temporal history faster (which costs more or generates noise).
Given how radiometrically simple your scene is, I’m honestly wondering if you could get away with using a hackier lighting solution that wouldn’t generate as much noise- a gradient ambient light+RTAO? I just don’t know what you could do to meaningfully hide the noise.
Thanks, I actually realised that I can make the material so bright that it looks as I want even without the supportive white floor, so its okay
i’m not sure if baking it would deliver the same quality. it prevents the world from flickering tho. that is correct.
ideally you would want to play backrooms with a soft shadow cast from the player model and would have to use lumen/manylights’ soft shadows for that anyway. and they will have unavoidable temporal noise.
My artifacts are now gone as I removed the white invisible floor, the only small problem now is that the shadows look a bit too dark on the top of the walls
You could add a skybox and set the skylight leaking parameter to boost the overall light. You could tint the skybox to be more muted colors, deleting volumetric clouds etc.
1 Like
Okay, thanks, I’m not at my PC anymore but I’ll try tomorrow. Btw, is there any way I could make it look almost exactly the same as this picture, but using less lights for better performance? I tried to play around with all the settings and lights, but still didn’t get anything I’d really like.I still feel like UE5 has to be capable of something like this, but maybe I’d really have to put there many more lights. I’d like to hear some advice.
The colors are quite different in my screenshots, I worked with a different reference, so don’t mind that. I focus on the lightning right now
So I decided to put there as many lights as needed, switching to normal shadowmap instead of virtual, which gave me around 40fps and only made the shadows sharper, and now I can run it in windowed mode on 75-80fps with the look that I wanted.
I would say, if soft shadows were required (it sounds like regular SMs might have done the job?) the player could be very well represented with capsule shadows. It would give soft shadowing at a pretty cheap cost and blend nicely with a static or dynamic environment. It sounds like the shadow artifacts have been solved tho?
New update, I spent some time on optimization and it turned out really well. I realised that I had max draw distance turned off, which gave me 10-20fps after turning it on. I also lowered the attenuation radius of all lights by 100 and I got another 5-10fps without any noticable visual change. That made it possible to play the game on 60fps even with VSM, with 1280x720 resolution on fullscreen. The lower resolution also gave it the feeling of an old camera, which is exactly what I wanted
1 Like