Path: utzoo!utgpu!water!watmath!clyde!bellcore!faline!thumper!ulysses!andante!mit-eddie!ll-xn!ames!pasteur!ucbvax!decwrl!sun!pitstop!sundc!seismo!uunet!portal!atari!kbad
From: kbad@atari.UUCP
Newsgroups: comp.sys.atari.st
Subject: Re: Mega Bug?
Message-ID: <1090@atari.UUCP>
Date: 11 Jul 88 00:31:38 GMT
References: <217@actisb.UUCP>
Organization: Atari Corp., Sunnyvale, CA
Lines: 38

in article <217@actisb.UUCP>, federico@actisb.UUCP (Federico Heinz) says:
> 
> In article <513@stag.UUCP> trb@stag.UUCP ( Todd Burkey ) writes:
>>
>>Has anyone had problems with programs 'losing the mouse pointer' on Mega 2
>>machines? [detailed description of problem deleted]
> 
> [some stuff deleted]
> My assumption that it was the application's fault was based on the fact
> that menus shouldn't drop while you update the screen, since one should
> "brace" the update code with a call that tells AES that you are changing
> the screen contents (I don't remember the function's name).

int wind_update(wi_ubegend)
int wi_ubegend;
The flag (wi_ubegend) can take on three values:
 0 => end update     2 => end mouse control
 1 => begin update   3 => begin mouse control
 
  Your analysis of the bug Todd described sounds quite reasonable.

> 
>   I had this bug happen with some applications, most notoriously with
> Uniterm and DLII, both by Simon Poole, both written in what's-it's-name
> Pascal, so I further suspected a bug in this Pascal's GEM support.

CCD Pascal.  I've noticed the same thing in UniTerm, running both on a
Mega 4 and a 1040 ST.  I have also seen this phenomenon in other PD software,
so it may not be the fault of the Pascal GEM support.  The moral of the story
is:
	GEM software authors, use wind_update!

> 		Federico Heinz                      "In Dubio Pro Libido"

-- 
 Ken Badertscher                 | Hey, umm, the stuff I said up there
 Atari R&D Software Test/Support | is, like, what _I_ think, okay?
 {portal,ames,imagen}!atari!kbad | So, y'know, don't bug Atari about it.