Very weird light artefacts.

kdobkowski

I have been creating an inn for my game project, and everything was going fine, building just fine, no artefacts etc.

I have re-imported the block out of the tavern as I wanted to remove some elements to fit the newly textured modules and built the light, this is what I get.



Someone suggested I increase the lightmap resolution from 64 to something higher. I did but nothing changed. Even on 2048 lightmap resolution I get same issue but more granular:



I am literally clueless in how to fix this.

I'm using Blender for modeling and Substance Painter for texturing and baking.

kdobkowski

Hmmm, I'm not sure how I solved this, but I simply went back to blender, and UV unwrapped the blocked out building (which is separate from the flooring, (wonder how that's linked in this case) re-imported it and built the light. The artefacts are gone...

Obscura

Please show an image of lighting only mode so we can see the error better. Also show your lightmass settings in the world settings panel.

kdobkowski

Obscura said:

Please show an image of lighting only mode so we can see the error better. Also show your lightmass settings in the world settings panel.

Hey Obscura, here are the images:



And the settings:

Obscura

You could test this simply. You could remove the uvs of the blockout mesh temporarily and make a new export, import it back into Unreal, bake again and see if the errors are back. If they do so, it means that incorrect or missing uvs can lead to light bounce artifacts.

kdobkowski

Obscura said:

You could test this simply. You could remove the uvs of the blockout mesh temporarily and make a new export, import it back into Unreal, bake again and see if the errors are back. If they do so, it means that incorrect or missing uvs can lead to light bounce artifacts.

You are right indeed, I did this and it was my "roof" planes I put in just to block out the sun from inside that had no UVs. I re-unwrapped the blockout model and re-imported to the engine, re-built the light and all looks beautiful!

Thanks a lot!!