Origin of shapes imported from FGDB seems arbitrary

Discussion created by edienske on Mar 13, 2013
Latest reply on Mar 20, 2013 by edienske
Here's something I haven't yet been able to figure out. I'm importing simple building footprints from FGDB into an empty scene. Although I have no street network, I do know what direction each model should face (in other words, which side of the model should be the front).This I'm trying to model based on the shape's first edge. Trouble is that the placement of the origin (and therefore first edge) of each shape seems completely arbitrary.

I would have thought it had something to do with the order of vertices of the 2D shapes, but I can't work out any logic - see attached image, which is a composition of 4 shapes from ArcMap showing vertices. I manually painted in purple lines where CityEngine places the first edge.

This is a problem, since I don't want to set the first edge of each footprint manually (it's a lot of houses). Besides, "set first edge" doesn't always seem to persist if I regenerate a lot of models. Exports to FGDB and KML also show random behaviour with origin placement.

So my question is: how does CityEngine work out where to put the origin of a shape imported from FGDB? Can I solve this problem in another way than manually setting each first edge?