Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!uunet!munnari.oz.au!diemen!tamar.compserv.utas.edu.au!pieman.compserv.utas.edu.au!tgray
From: tgray@pieman.compserv.utas.edu.au (Tony Gray)
Newsgroups: comp.sys.atari.st
Subject: Re: STacy review in EM
Message-ID: <1991Jan30.203650.28@tamar.compserv.utas.edu.au>
Date: 30 Jan 91 10:36:49 GMT
References: <1991Jan29.110121.10806@actrix.gen.nz> <1991Jan29.233400.28092@rice.edu> <40711@ucbvax.BERKELEY.EDU>
Organization: University of Tasmania - Launceston (formerly TSIT)
Lines: 49
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In article <40711@ucbvax.BERKELEY.EDU> emerson@gandalf.Berkeley.EDU (Emerson Mei) writes:
    < stuff deleted >
>software got a D grade (that is GEM, not apps) one complaint the
>reviewer had was that GEM required a 1/2 to 1 second pause before an
>initial click in a click-drag manipulation otherwise the drag would 
>fail.  Is this a problem I'm not aware of? I have a Mega & a 520 & 
>they seem OK.  If their reviewer is indeed seeing things that are 
>;not there perhaps everyone can write a letter to the magazine.
>
>Sorry I couldn't quote the magazine directly.

What the reviewer was probably referring to (without realising it) is the
way GEM handles a double-click.  The first time you click the mouse, GEM
waits a preset period of time (as set in the mouse double-click speed, in
the control panel) to decide whether you will make a double-click.  If
you haven't pressed the button again within the time frame, a single-click
event is posted - if you have, it is posted as a double-click.  This is
quite different to the way the Mac OS (for instance) handles a double
click.  With the Mac, a click posts a select event immediately.  If
a second click is made within the double-click period, a second, double
click event is posted.

If you set the double-click speed of both the Mac and the Atari real slow,
you can actually see that the Mac gives visual feedback immediately after
the first click of a double-click (eg., an icon changes its visual
appearance) whereas the Atari waits until after the second click to
give visual feedback.

If the magazine reviewer had set the double-click speed to the slowest
setting, he (she?) would have observed the delay you mention, ie. a delay
after holding the mouse down before a drag could take place.

It is interesting - this single technique alone causes a large difference
in feel between GEM and the Mac OS, and makes GEM seem "sluggish".  Perhaps
if a patch could be made to GEM to allow a single click to be posted
immediately one occurs, with a second post (as a double-click) if another
click was observed on the same pixel within the time period, then 
GEM would feel faster (or smoother).  But then again... who knows what
other programs would break!

If you were coding your own application, it would not be too hard using
the normal AES calls to simulate the Macintosh approach.

Hope that helps!
-- 
-------------------------------------------------------------------------------
Tony Gray                             AARNET: tgray@pieman.compserv.utas.edu.au
School of Applied Computing           Phone : (003) 260 366
University of Tasmania - Launceston   CIS   : 74010,1556