6 face orientation are different of one box

1. create one box;

2. get 6 faces of the box

3, I assued that all 6 faces orientation are same, but 3 are forward, and 3 reversed, why?


Kirill Gavrilov's picture

From modeling point of view forward-oriented shape orientation has no advantages over reversed one, and mixed orientation happens all the time in complex shapes (and difficult to avoid).
So I suppose this is just how BRepPrimAPI_MakeBox algorithm has been implemented - you may try building a box step-by-step in your own way.