I was tinkering with Away3D and the x-ray method and it ended up with a flashlight effect, see the attached picture for still snapshot, or go to http://dhkgames.com/games/redshifted/ for a real-time test. Click on the stage and use Q/E keys to rotate the flashlight and see the results. The female model is being rendered with idle animation. use the LEFT and RIGHT keys to rotate the female model.
Thanks!