I'm not talking about the user writing code to move an object. I'm talking about the user clicking features on 3D objects with their mouse (like a specific vertex), having those features become highlighted, drawing the visual cues that let the user know that they are in "Move" mode, showing distances and angles to give the user the necessary feedback, clipping to features like midpoints, etc.

Really, the piece that drove me to eventually give up was getting a vertex or edge to be selected, rather than the whole object. Its not difficult to calculate for simple shapes, but what is really needed is a general solution, that doesn't depend on shapes being regular polygons.