Why do my lightmaps look terrible?

Hello, I have been trying to fix this for hours but I couldn’t. In some areas my lightmaps look just fine but in some areas they disgust me.

I provided some images down below with explanation.

Additional information: The scene is generally built with the default cube and plane. There is no light coming from the back face of the planes.

I really need to have good global illumination in this game so any help is appreciated.

The weird area:

Generally the lightmaps look good:

The part on the left is the buggy area, the part on the right and top right is the good area:

A better look:

There is bad in the good too, just like ying yang!:

It mostly looks like your meshes don’t have proper lightmap UVs.
As said here in the doc :

The easiest way to do this is to open the Mesh import settings and enable the Generate Lightmap UVs setting.

And here is a more detailed page about lightmap UVs.

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I used these meshes in my projects before which has great lightmaps. I think this is caused by other stuff. Thanks for the help tho i’ll try that.

Didn’t work. Here are my lighting settings if that helps.

My mesh settings look like this:

Texel validity:

UV overlap:

UV charts:

Directionality:

I’m going crazy over this…

So, I lowkey obsessed over it a lot and fixed some of the texel validity issues here:

But there still is some here. Why?

Mentioning the manual :

If a significant portion of a texel’s rays are hitting backface geometry, this texel is marked invalid.

Looking at your screenshot I think it’s because rays cast from the texels of the walls are hitting the back faces of the plat leaves ?

Try to look at the leaves render/material to properly handle this, or if the lightmap baking doesn’t result in awful results maybe it can be ignored ?

Texel invalidity usually means you have exposed backfaces. You can use the “Highlight Back-Facing Geometry” toggle on the overlay to debug that. Alternatively, you can enabled double-sided GI on your materials, or adjust the global backface tolerance. See here for info Lightmapping Troubleshooting Guide - #16 by kristijonas_unity