Michael,

I noticed center snapping on a full sphere, 1/4, and 1/8, and that propertiesPanel.hasRadius seems to be true for any fragment of a sphere, but I guess those are special cases. Thanks for explaining that the center snap point is coming from trim curves.

re:
> adding in some script access for conic sections on faces

I don't understand what this means. To me a conic section means a curve.

The problem I'm trying to solve is getting the UV directions on a spherical face to go in the directions that I want. My plan was select the face, get the radius and center, cache the trim curves of the original face, generate a sphere with the same radius and center but with seam orientation picked with something like an orientation picker, remove the original face, trim this new sphere with the cached trim curves, and then join.

I guess I could draw 2 pointObjects snapped to the surface of the face, dropPoint to get uv coordinate points, evaluate normal at each of the uv points, extend a line along each normal, and find the intersection = center. Is that the best way?