You will lucky to find something readymade for VPython.
This looks like it would be helpful for finding dome corrdinates,
which you can then use to plug-in to VPython:
http://www.applied-synergetics.com/ashp/html/domes.html
And Kirby is probably an excellent source of information in the area
of the intersection of domes/Python/VPython. He knows a good deal
about each of these things.
I don't know whether he monitors this list. You might try posting to
(e-mail address removed) which I know he monitors, to see if he has
something to suggest.
I might have some other suggestions if a understood what you were
trying to accomplish, and why.
Art