UV map problems with Multiple CAD parts imported via Datasmith


I’m having a problem when importing large interior models to UE via Datasmith from Autodesk Inventor.

The UV maps seem to be broken and they pretty much all look like this with strange dark regions. I’m also getting a ton of Lightmap UV overlapping errors.


When editing parts UV Channel 0 is often completely broken and doesn’t fit the box at all. UV Channel 1 looks fine. Due to the number of unique parts that are in the thousands, I can’t just go and try to fix them one by one and it doesn’t seem to help either.

So far I’ve tried unwrapping the UV map on all parts, merging actors and trying to solve the UV issues that way but they doesn’t see to fix anything.

How can I solve these issues?


If your uv channel 1 looks ok then you can select all your meshes and set the lightmap channel to 1…


thanks for answering. How do I change the Lightmap channel for multiple meshes? There’s Lighting channels but that’s a whole different thing, right?


Select your assets in the Content Browser, right click → Asset Actions - Bulk Edit via Property Matrix…
And there under Static Meshyou’ll have the Light Map Coordinate Index!


thank you. That helped me a lot. I’m still seeing some artifacts and other weirdness but that definately solved a lot of issues!