UDK Normal Map seam issue from Xnormal

easterislandnick

Hi, I am exporting normal maps to UDK via Xnormal and am getting really bad seams, I've searched around but can't find a solution. The UV layout is shown as is the model in maya. I have set +Y to be -Y in Xnormal which should help shouldn't it? Is it because parts of the UV layout have been rotated? I have checked they are not flipped. Any ideas?

Visceral

From my understanding UDK will make smoothing groups base of your UV islands. So when you break the UV's it will create a new smoothing group for you. Can you post the normal map aswell?

JordanW

Visceral that doesn't sound correct.

Does your model have smoothing groups? You should be able to give it 1 smothing group for generating your normals in xnormal and for use in UDK

omid3098

and if your smooth group is correct, try to flip green channel of normal texture..

Visceral

JordanW wrote: »

Visceral that doesn't sound correct.

Does your model have smoothing groups? You should be able to give it 1 smothing group for generating your normals in xnormal and for use in UDK

If you dont have assigned smoothing groups ( i dont know how this works in Maya) UDK usually does its best to assign smoothing to the model. However if we could see the Normal map for the thing i think that would give us the information if this is a UDK issue or a xNormal issue.

Simmo

Visceral is right, once you bring your model into Unreal, regardless of smoothing groups it will break the smoothing based on UV seams/islands.

If you want to get a correct bake, just break the smoothing groups at the UV seams (as they'll be broken in UDK) and re-bake your normals. It should show up as you intend it to.

It keeps all of the smoothing groups you assign as well, just there will always be hard edges on UV seams. Just the way it works, hope this helps

Gilgamesh

For maya, just harden the uv seams edges to get a real view of how things will look, and adjust the normal map accordingly

Stitch626

I have the exact problem and the maya harden uv island border edges then re-bake the normals using transfer maps doesn't work... it does tweak the output map a slight bit, then you invert the green channel and re-import into udk to check the update, but it doesn't make a difference...