	Purpose
Animate a bouncing ball on a background.

	Method
Use BitBlt to erase the ball. Then draw the ball in its new location. When
the ball gets too close to the edge of the picture, reverse the sign of its
X or Y velocity.

	Disclaimer
This example program is provided "as is" with no warranty of any kind. It is
intended for demonstration purposes only. In particular, it does no error
handling. 