Problems with seams on static mesh.

Hey guys. I’m new to the forums and pretty green with UE4 too.

I’ve been working on an environment and having trouble with seams on my models. Here’s a pic:

Is this just something thats unavoidable? or can someone please point me in the right direction of what I need to learn to fix these problems?


I think its UV maps. Make sure both sides of seam have continuous normal map.

If its not that, please post normal map, material graph etc. Without more info all is really guessing game.

PS. it may be also variant of lightmap leaking. So check UVs for light channel. Btw you also have seas on floor tiles.

Okay here’s some more info:

I also get this seam problem when I’m not using a normal map. So the material setup is just a constant node with a value of .5 plugged into the base color and a 0 plugged into metalllic.

Here’s the mesh again, without the normal map:

and I’ve been letting Ue4 generate my lightmap UVS as I read thats supposed to be a pretty effective method:

It’s not that you did anything wrong. This problem is not 100% avoidable, but this error can happen when the edge of your UV is lined up in-between pixels, causing it to wrongly pick between a shadowed or unshadowed pixel. I also rely on Unreal’s UV remapping, and I was hoping that it would automatically snap straight edges to pixels, but I usually don’t have issues. Check out this World of Level Design article and scroll down halfway to where it says “Seams Caused by in-between Pixel UV Edges”. Basically you snap your UV edge to a grid that matches your Lightmap resolution. If that doesn’t fix it, there isn’t really a reasonable fix and you may have to live with it.

They are using UDK, but the principles still apply.

Lay out your UVs so that the edges of the cylinder piece are exactly at left and right edges of the UV space. That’ll make the seams on that disappear.

Thanks for the help guys. I looked into fixing the lightmap UVs properly. I think I got them working. It looks pretty good now, except for a certain part at the base of the mesh. It seems to be more obvious when its in shadow.

It looks pretty much perfect in the first shot.