GETFRAME returns a movie frame. The frame is a snapshot of the current axis.
No it bloody well isn’t.
GETFRAME (as least on OS X) captures a snapshot of the portion of the display screen that might or might or might not have the current axis on top. If you have a long-running script to produce an animation, you might be tempted to switch over to read email or a PDF while your animation renders. In which case, when all is finished, you’ll find yourself a nice AVI file full of your email and none of your calculations. You want to render animations using
GETFRAME, better have a single task computer to dedicate to it, and make sure to turn off the screen saver. What is this, 1992?