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From: h+@nada.kth.se
Newsgroups: comp.sys.mac.programmer
Subject: Re: Drawing all over the desktop
Message-ID: <1990Jun30.160944.1007@kth.se>
Date: 30 Jun 90 16:09:44 GMT
Sender: news@kth.se  (News Administrator)
Organization: Royal Institute of Technology
Lines: 29

larsen@ginger.Princeton.EDU writes:
---
I know that Apple doesn't want applications to draw all over the desktop.
Since I'm doing it anyway, though, I need advice in order to do it as cleanly
as possible.  At the moment I'm checking screen depth and writing into video
memory, but I would prefer a quickdraw solution.
---

The stuff to do is drawing into the WMgrPort. This is as
compatible as it gets, though that isn't very. You have
to be VERY careful to restore everything as it was before
you call {Get/Wait}NextEvent. This means ony XORing, among
other things. (Well, if it's a game and you don't want it
to be MF compatible nor System 7 compatible, you don't have
to restore the drawings, just the state of the WMgrPort)

I have written an INIT that, among other things, needs to draw
in the WMgrPort, called SetWindow INIT. The source and the
init is available via FTP from rascal.ics.utexas.edu, and is
in the directory mac/hacking (if memory serves me right,
might be programming or somewhere completely else...)

Generally, it is a VERY BAD idea to draw outside of windows.
Only newly-converted MS-DOS programmers try and do this
without a good reason. (And I mean GOOD)

Happy hacking,

						h+