[comp.sys.mac.programmer] Using offscreen bitmaps...

franco@bbn.com (Frank A. Lonigro) (12/10/88)

	I'm having a heck of a time getting offscreen bitmaps to work.  I've
tried defining a window with portRect, portBits.bounds and visRgn.bounds
to be (-512, -342, 0, 0), but when I CopyBits stuff to it and then back to
the screen, I get garbage.  What am I doing wrong?  How do you define and
use offscreen bitmaps??  I really think I'm going to need some sample 'C'
or Pascal code to do this because I'm totaly confused.  I understand what
needs to be done to produce "flicker" free animation, but I can't figure
out how to write it in code form and get it to work.

	Please, can someone hack up one of their graphics programs that
uses offscreen bitmaps to show me code fragments on how to use and define
them.

Thanks, in advance,
-franco

franco@bbn.com
franco%bbn.com@relay.cs.net
...!harvard!bbn!franco