Subject: Re: Hypercube in lisp (newbie)
From: (Rob Warnock)
Date: Thu, 25 Aug 2005 03:29:02 -0500
Newsgroups: comp.lang.lisp
Message-ID: <>
LuisGLopez <> wrote:
| Exactly! I forgot to do (require :clx) (shame on me!)
| Now a beautiful window pops up immediately, but no polygon is drawn,
| although I get no error from   (draw-polygon (list (point 20 120)
| (point 120 220) (point 220 120) (point 120 20))))

Works fine for me in CMUCL-19a. Did you somehow fail to copy the

Or perhaps was your pop-up window covered when you did the DRAW-POLYGON
call? Remember, Pascal's example is *very* simple code, and does not
contain an exposure event handler, so if the section of window you're
drawing into is not completely visible when you call DRAW-POLYGON,
you won't see anything at all. Move the drawn-to window somewhere
so that at least the top-left quadrant is visible, and then try the
above DRAW-POLYGON call again.

[Then drag another window across part of your nice polygon, and
watch it get erased...  ;-}  ...until you call DRAW-POLYGON again.]


Rob Warnock			<>
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