Graphics-wise, the assumptions are quite different. Game scenes are a large collection of low-detail objects that are constantly moving and not all visible at o

Graphics-wise, the assumptions are quite different. Game scenes are a large collection of low-detail objects that are constantly moving and not all visible at once. CAD scenes are a small collection of high-detail objects that don't move except in response to input events. If the CAD project is big and serious, I would be afraid of eventually hitting some limitation of the game engine that is hard to work around due to such different assumptions.