Of course, the sensible thing would be to use an existing game engine, but after a certain point, there is some curiosity if learning and fighting yet another game engine is really quicker that just writing something from scratch.
With this personal project I have endeavoured to create a short animated sequence simulating live-action using a number of Photoshop-created layers projected on to 2D and 3D cards (modelled in Modo) in NukeX 9.
The sequence is HD but regrettably, viewing in HD is restricted for embedded Vimeo videos so if you cannot see it in HD here, you can still view it directly at Vimeo. Simply click on the HD button to view in HD.