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From: Christopher Self <cself@btinternet.com>
Newsgroups: comp.sys.acorn.programmer
Subject: Re: dragging a text icon by its outline
Date: Sun, 14 Aug 2022 18:42:04 +0100
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I've even managed to clip it correctly now:

 block!8  = minx% - (scrollx% - icminx%)
   IF scrollx% > icminx% THEN block!8  = minx%+4
 block!12 = maxy% - (scrolly% - icminy%)
 block!16 = minx% - (scrollx% - icmaxx%)
   IF maxx% + (scrollx% - minx%) < icmaxx% THEN block!16 = maxx%-4
 block!20 = maxy% - (scrolly% - icmaxy%)

But I still don't understand it...

-- 
Christopher Self