I’m working on a scene that has low lighting and the light creates some weird circular lines that look like this:
I tried tweaking all kinds of lighting and graphics settings, but nothing seems to help. The only thing is to increase the light intensity - this improves the situation, but the scene needs to be low lit.
Is there anything I can do to fix that?
These are my settings - I’m using URP:
Thanks!
Disable “Compression” option from the rendering settings window
Don’t forget that all indirect lights (sky light, area light, emissive materials) has much more noise compare to the direct lights(directional, spot, point) so you must increase the Indirect Samples from the rendering settings window
Also you can use fake indirect lighting simulation:
Thank you for the reply!
I edited the original post to upload a new screenshot that makes it a bit easier to see the problem.
This is an indoor scene - inside a white cube. There’s only one light source - a spot light, pointed at the center of the floor.
I tried increasing the direct and indirect samples to 1024, but I don’t think I see much of a difference.
Also I don’t have a compression checkbox in the rendering settings (I’m using Unity 2020.3), I have that in the lighting settings and it’s turned off. These are my rendering settings:
And thanks for the video, I’ll check it out.
Got it, that’s turned off, I’ve attached these settings in the first post.
But unfortunately the problem is still there.
This problem is 100% related to the compressing and the lightmap size
Now you have disabled the compressing so your problem is the lightmap size
Also don’t forget that the white surface is not a good place for testing. Also you can use post processing (gamma and contrast) to hide these problem
Now find the lightmap size and increase it (4096)
Hmm, I rebaked it with 4096 lightmap size, but it’s still the same thing.
Here’s a screenshot:
I’ll try with post processing tomorrow.
This is the limitation of the rendering the lightmaps
Have you tried playing with filtering ?
So the “max lightmap size” is not the correct setting? I can’t find another lightmap size setting though, tried increasing the “lightmap resolution” from 40 to 80, but still the same.
I did, it’s currently set to Auto, I tried tweaking the settings in “Advanced”, but it didn’t help.
What helped the most is enabling “Post processing” and then “Dithering” on the camera. This caused like 50% improvement and it’s almost ok, but I still wish I could improve it a bit more.
This is a technical limitation… Especially happens when you are in the Android mode of the editor (or other low end-platforms)
Using post processing (Gamma ,Exposure, Contrast) you can hide it
Also you can use textured models
I see. I’m building for PC (for VR) and the problem becomes more visible in VR and in low lighting conditions.
At least I found the name of this phenomenon - color banding and there’s a lot of info on the topic.
Basically the way to improve it is with dithering, enabling HDR, playing with the grading mode and LUT size - these helped a lot, but it’s still not good enough.
So I guess I’ll have to redesign the scene to not be low-lit.
I think using HDR light maps should fix this. HDR maps and high quality compression. Set lightmap quality to high in Player Settings.
Thanks for the tip. The “Lightmap encoding” is set to high quality and with dithering and HDR, I think it looks the way it’s supposed to look. I guess you can’t completely eliminate these lines, at least in URP (I may be wrong though). I think the problem now comes mostly from the colors that are used - black and white. In another scene that uses different, more realistic colors, the banding is still there, but it’s not noticeable.
So I decided to redesign it a bit and put more light in there - it looks ok now.
You can see the problem on the Unreal Engine 4 lightmap:
With HDR lightmaps, HDR enabled in the camera (and project in general) and dithering in post, this should be (almost?) eliminated.
