Issue with baking Lights on specific object!?

Development Rendering
1

So I made a this building but I’m having an odd issue when baking the lights to test.

So when I keep the building all one mesh (Main structure+windows) It won’t Bake correctly and I still get no errors. (Bottom Building)
I’ve tried merging the meshes both in Maya and just with the options when importing FBX noth had bad results.
When I separate the meshes everything seems to bake just pretty fine.(TopBuilding)

So I’m assuming it’s an issue with the windows. They’re currently just planes and I’ve tried making them thick and that did nothing.
Also another thing to note is that it gives me like 7 UV channels with the windows even though they are all uv’d.

Any ideas why???

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My last resort right now is to try and remake the windows but I can’t see that fixing anything?

2

Check normals, check UV’s, did you put Skylight also? You have a different material for windows on mesh? You made glass material and apply?

You need only 1 UV channel per material.

3

I actually decided to remake the windows and that seemed to fix it somehow! Thanks though!

But now I have another small issue(I’m new to a lot of this if you can’t tell, hah)
Just odd artifacts with my lightmap. I have it generating UV lightmaps off of my UV and they look like they should work just fine?

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On a side note, How exactly can I make custom lightmaps or start from the one that is generated to make less islands?

4

This is because, you want to cover with a small lightmap texture a big object.

You have 2 solutions:

  1. increase lightmap resolution for that particular mesh ( if you look at the lightmaps UV’s if the lightmap resolution is not big enough you may have 1 or less pixels mapped per face, and that is far enough).
  2. split mesh in more pieces to have separate lightmaps. You can also benefit from geometry instancing i think.