3d mapping the set pieces wouldn’t be terribly complicated, but if they’re moving? That’s a whole mother issue. Then you’re talking about real-time tracking that has to be very accurate or the illusion falls apart. That’s pretty high end, like BlackTrax.
http://blacktrax.cast-soft.com/howitworks/
Unless you don’t need to project on the shapes *while* they’re moving, just at two different positions during the show. In which case you’d just need two different setups and make sure your stage hands are really accurate with their placement marks.