Direct Draw example program 4.  

Adds functionality to example program 3.  Creates a flipping surface and 
loads a bitmap image into an offscreen surface.  Uses BltFast to copy 
portions of the offscreen surface to the back buffer to generate an 
animation.  

Illustrates watching the return code from BltFast to prevent tearing.

This program requires 1.2 Meg of video ram.
