[Inkscape-devel] How to convert Inkscape items to "ordinary" shapes?

Hi,

what do I need to do when I want to convert an Inkscape-specific SPItem (like star, spiral, etc.) to an ordinary shape? Is it enough to set "sodipodi:type" to NULL? But what if there are any pointers left that refer to the "old" SPObject and expect it to be of the given type? How is that handled within Inkscape? I've encountered functions like ConvertToShape and ConvertToForme but am not quite sure what precisely they do, and furthermore my use case is converting 3D boxes to ordinary groups (while at the same time converting their sides to ordinary paths) so that I guess neither of these exactly fits my needs.

Thanks for any hints, Max