Cage:

ok. i tried it and it works and i can apply the materials to it. cool. the code looks pretty clear to me although the subject matter is new.

i understand little of this or where it's going. if i transfer only the vertices i want to retain, does that then create a new geometry that works and if so are the groups retained? am i getting the gist of this at all?

my purpose would be what i mentioned above, for example to create a fishbowl in 2 parts so that they could be positioned around the fish (in the 2d rendered versions).