Shading problems on a WiP model.
I've been working on the Brown Streak train I posted a while back, and have made some progress, but I seem to have hit a huge problem.
After correctly dirt-mapping the bodyshell of the train, it started displaying this very weird shading bug.
Here's a picture:
In Zmodeler 3:
I've tried the most obvious thing already, calculating normals, but that didn't work.