In the GlobalGeometryRules object the field Starting Vertex Position defines the first vertex in the surface perimeter. The options are UpperLeftCorner, LowerLeftCorner, UpperRightCorner, or LowerRightCorner. This is simple enough for vertical surfaces where "Upper" and "Lower" refer to the z-axis, and "Left" and "Right" are as seen from outside the surface.
However, if the surface is horizontal then up, down, left and right are undefined.
So is there a suggested way to order the vertices of a horizontal surface? Does it matter what order they are in for horizontal surfaces?
