This article is from the Mac Programming FAQ, by Jon Watte h+@austin.metrowerks.com with numerous contributions by others.
When recording pictures, you have to set the clipping area to exactly
the frame of the picture you are recording. This is because it is
initally set at -32768,32727 in both directions, and offsetting the
picture even one pixel when drawing it will result in the region
wrapping around and becoming empty.
When recording pictures, do this:
*code* PicHandle h = OpenPicture ( & theRect ) ; ClipRect ( & theRect ) ; /* draw the picture */ ClosePicture ( ) ; *end*
 
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