Weird lighting issue

After light building some of my models have strange shading, as if the UVs are inverted. I’m still a noob in Unreal so I have no idea what the issue could be.



Hey there @Misstarretje! Could it be that some of the face normals are off? If any of the faces are facing backwards, you can often see this effect!

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Thanks for the help! (Sorry for my late reply, though)
I did several normal checks in Maya, exported new versions to Unreal but it doesn’t seem to be the problem. When I make a render in Maya, everything looks normal but in Unreal it’s living its own life.

Pretty sure you just need higher resolution light maps. There’s areas where one or two pixels are describing shading on a complex surface.

Hmm okay so I gotta bump it up until the blue areas are turning green?

Try going over kill first and making the green areas red.


The blue edges don’t seem to change at all, that’s pretty weird since the UVs are completely fine

Oh I fixed it! I had to put both lightmap resolutions on 512, even though the thinnest edges still remain blue but it doesn’t give any weird issues now. Thanks for the help guys!

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Oops, disregard the last thing I said, the issue is still there

Oh sorry to hear it didn’t work! Are there overlapping edges/hidden faces? I see the UVs get really tiny at some points.

The UVs look like this, the big parts overlap because someone told me it’s okay as long as you don’t bake, but maybe that’s why it’s causing issues?


Well… you’re trying to bake. So probably… But if you generated a lightmap UV in unreal (defaults to being put in UV channel 1) then it should remove overlaps when it can

I’d also suggest you try moving your lightsources a few cm away from any nearby surfaces, seems like your candle light is really close to the wall which can cause issues with lightmap baking.

I concur with Ark, could be that the light sources. Possibly rebake?