Flicker Prevention 2
lInstead
of painting the background, then drawing on it,
it is better to ÒpaintÓ a complete image covering
the visible area of the Frame.
lThis
image is known as an
off-screen buffer
because the buffer is not part of the Frame.
off-screen buffer
because the buffer is not part of the Frame.
lThe
buffer is drawn on prior to update().
lThe
buffer contents is then painted in update().
l