Hi Marcus, yes for Modo and Lightwave both I'd definitely recommend LWO format and not OBJ.

Modo's OBJ importer has actually improved quite a bit from where it used to be, it used to have even more significant problems than what you are showing there. But even though it has improved it still has a ways to go yet.

That's actually why I developed a LWO exporter from MoI in the first place, it was specifically because their OBJ importer had a lot of problems, especially with n-gon processing.


Both Modo and LightWave use a kind of sensitive method for determining the orientation of a polygon - they only look at the directions coming off of the very first vertex of the polygon to determine its orientation. So that means the first vertex must be located at a convex vertex for the polygon to behave as intended. I think that possibly one of their main problems is the OBJ importer may not be setting the first vertex of the polygon carefully.


It would actually be a major improvement for them to use a different method in their core handling for determining the polygon's orientation, like the Newell method that analyzes all points of the polygon instead of putting special weight on the first one, there is a link to that method in this previous post:
http://moi3d.com/forum/index.php?webtag=MOI&msg=2039.7

- Michael