Texture Mapping Inconsistency between Painter and Unreal Engine

[AnotherConcernedCitizen]

Hi all, I am having a problem with my exported texture maps from painter to UE (4.26). Everything looks great in Painter (1st image), however once importing to Unreal some (but not all) textures seem to be shifted with respect to the UV maps (I used a UDIM/Tiled workflow from blender).

I found an older post that recommended triangulating the mesh from Blender 2.91 (I used triangulate modifiers at the end of the stack on all objects w/ the "Keep Normals" checked on. These modifiers are applied at export of the FBX)

Painter Viewport: 

UE Viewport:

Painter Export Settings:

...weird huh? Anyone run into this problem beofre? Since the problem doesn't exist everywhere (actually most of the texture maps/UV are aligned correctly in UE), I'm not sure the UDIM workflow is to blame here, but any clues as to what I should try are welcomed!

Thanks!

[AnotherConcernedCitizen]

I should specify that this model is a skeletal mesh, so I am importing the blender-exported FBX in both Painter and UE (as far as I can tell, FBX Mesh Export from Painter does not carry the skeleton and weights with it)

[Fabrice Piquet - Froyok]

My guess would be that the triangulation between Painter and the Unreal Engine produce different result here, it can sometimes leads to different interpretation of the UV coordinates.

You should triangule your mesh before importing it in Painter to fix that problem, then re-export.

[AnotherConcernedCitizen · Accepted solution]

Turns out it was an Unreal Engine setting. In the mesh, there is a parameter called "use full precision UVs". That fixed it!