Wrong UV imported in UDK

Jerc

Hi all,

I have the strangest bug in UDK. I updated a mesh I had imported earlier with new geometry and UV mapping.
The thing is, when I re-import my mesh, the new geometry is there but the old messed up UV mapping is still there.

I tried deleting completely the mesh from my UPK, saving, restarting UDK, importing with a different name, in a different package... no matter what, when I import this mesh it imports it with the old UVs that are not even on any model on my hard drive anymore.

It's like there is some sort of hidden cache in UDK that recognizes the mesh from before and applies it the old UV, even if I change the name of the .fbx file.

3ds max, Xnormal and 3d Coat all read the file correctly so it's definitely not an issue with the FBX file but rather with UDK being stuck on some old version of the file...

passerby

use the model viewer in udk to check out all the UV channels, and set which one is used for lightmaps

Jerc

It's not a lightmap issue, it's my primary UV and I only have one uv channel on this mesh.
It's just that UDK doesn't seem to update the uv along with the geometry of this mesh, as if he had stored the uv at some point and just uses that instead of the right one actually present in the fbx.

On the left, the uv layout in Max, on the right, the uv layout in UDK.

Jerc

I fanally got it to work by attaching another mesh to this one, breaking the vertices index and detaching it again. It seems UDK indeed keep older versions of the meshes you imported and messes up sometimes between versions.