I've noticed that this topic has been coming up a lot, without a conclusive solution, so: Is there a unique way to determine an outwards facing face normal? I've tried GProps, SLProps, using orientation info to invert the normals, you name it. However, some faces still get culled, some don't but their normals are funky, e.g. when you look straight at 'em the surface is dark, while some faces are displayed correctly etc.
So, has anyone come up with an immaculate solution to this? Otherwise I'm gonna be rummaging through OC's Viewer code all night long.