Lighting issues in build (blender, possible lightmap issue?)

Development Rendering
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Hello, I’ve been trying to get this to work for some hours and am getting a bit frustrated. I’ll jump into it. The model looks like this:

But it is rendering like this once I build lighting:

This clearly looks pretty weird. I read around a bit, including other stuff on here, and decided it must be a lightmap issue. So I found out how to create a second UV map in blender, and went ahead and created the following lightmap:

Same issue. I tried again with the lightmap pack option. Same issue. I tried manually forcing the lightmap resolution to be 1024 like the lightmap generated was. Same issue. I think the first image shows that the mesh itself is fine since the engine could light it dynamically. Any idea what could be causing this? It’s driving me crazy.

2

Hello Deldrith,

I am going to link you to our official documentation on lightmapping for UE4.

There is a sections specifically about unwrapping.

What I can tell from a glance is that many of your UV’s are incredibly thin and take up little space. This can cause artifacting issues.

The other issue is that lightmaps will try their best to calculate across where you have seams. However, the map is broken at this point. Try to make sure you line your edges up where you have seams.

Link : Understanding Lightmapping in Unreal Engine | Unreal Engine 5.1 Documentation

Thanks,