There may be one convoluted way to do this--mind you I haven't tried it, but it should work. There are several programs, such as PhotoModeler (Lite version is free demo) that will allow one to make 3D meshes out of a series of photographs of an object taken from several different angles. Suppose you used such a program, but instead of photos, you use several different renderings of your object in Bryce--each rendering from a different angle. I don't know why this wouldn't work. Sorry no link for PhotoModeler. Somewhere in the Renderosity forums there are several threads discussing these sorts of programs (most are quite expensive; some are easier to use than PhotoModeler). If my explanation isn't clear, let me know and I'll try to be more precise.