Huge lightmap artifacts

When Ive rebuilt my static lighting, it made artifacts on some meshes, on most of them It has been fixed by setting world parameter “indirect lighting smoothness” to value 10, but on others it doesnt seam to help.

Could it be the lightmap resolution of the meshes?

Have you looked at the scene in lightmap density mode?:

yep. it is on red - hi resolution, lightmap is 512x512
this artifact is not connected to UV seams or lightmap resolution

Ok, then you have the mysterious luminous squares problem. I have it on statically light landscapes. I have seen other people reporting it. I’m afraid I have no seen a solution yet…

It could be VLM settings. Lower detail cell size, and higher maximum memory data per sample, specifically…is what’s suggested. It’s supposed to give finer shadowing and lighting detail. Watching a video in the online learning section about it can help in how to get more detail / quality from the VLM (Volumetric Lightmap). It’s interesting to see this problem over and over, and not even experienced developers know what to do about it. I’m not sure either, but I thought it would be mostly resolved by 4.25.1.

I’d be interested to hear if you find a solution to this, me a quite a few others are getting these ‘magic’ squares, especially on landscape…

I think it has something to do with uneven and/or misaligned sample calculations in the V. lightmap grid.

It doesnt help, screw this unreal engine, now Im baking shadows in blender

I fixed this by checking Force No Precomputed Lighting and baked twice. This will remove all lightmaps, rebaked and it fixed it. I give no guarantees, though.

Also having this issue on 4.27, it’s a project intended for Oculus Quest 2, but the thing is I keep getting these huge artifacts that doesn’t make any sense


Any solution you found?