Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!uunet!cbmvax!daveh
From: daveh@cbmvax.commodore.com (Dave Haynie)
Newsgroups: comp.sys.ibm.pc
Subject: Re: 'Virtual Monitors'
Message-ID: <9212@cbmvax.commodore.com>
Date: 4 Jan 90 18:39:44 GMT
References: <3329@cpoint.UUCP>
Distribution: usa
Organization: Commodore, West Chester, PA
Lines: 54

in article <3329@cpoint.UUCP>, alien@cpoint.UUCP (Alien Wells) says:
> Xref: cbmvax comp.sys.ibm.pc:45649 comp.sys.mac:48839

> In article <9191@cbmvax.commodore.com> daveh@cbmvax.commodore.com (Dave Haynie) writes:
>>...  The Amiga's Intuition interface has a feature that's more
>>like what I'd think of as virtual monitors -- it can support any number of
>>separate monitor displays on a single monitor, via kind of a superwindow
>>called a Screen.  

> I will grant you that separate screens can give you a certain organization 
> and functional grouping of your windows, but amiga screens are a cludgy way
> to implement it.  

If you think screens are a kludge, you don't understand them.  They're actually 
quite an excellent facility.  Sure, the Mac hasn't had much need for them, yet,
other than possibly for grouping of things.  That's probably why you don't see
their other uses.

> If I wanted to do something similar for the mac, I would make a type of 
> desktop-window that contained a desktop.  Clicking on the desktop-window would 
> activate that desktop.  

Additional "desktops" in windows aside, you're missing the point.  Screens give
you instantaneous movement between the different "desktops", or whatever else
you put on them.  Exactly as fast as turning your head between one of several
monitors, only considerably less expensive.  I use a Mac in the lab, I know how
slow the thing is at reordering windows.  It would very likely be worse at
reordering windows within windows.  Screens take practically no work to manage
(in fact on the Amiga, the only time any CPU time is involved is when you're
moving them; once in place, the video system manages any screen setup for free),
any window shuffling on any window system takes effort, and generally gets worse
as the number of windows increases.

The Mac IIci is the first Apple that could really take advantage of this concept,
at least to it's fullest extent, because its on-board video logic works much
like a simplified Amiga video system.  It can display different resolutions, and
the higher resolutions can have an impact on system performance.  You don't 
need 8 bit pixels in a VT100 emulator, so why not place that emulator on a 
screen display that uses 1 bit pixels.  Not only will there be less hardware
load when you're using that screen, but less software load actually displaying
that output.  Sure, you can always call up your configuration DA and cut down
to 1 bit pixels when you fire up the terminal program.  But what would you do
when you're running several things?  If one application needs all 8 bitplanes,
all of them are going to suffer the overhead involved in driving that display
(especially because the Mac isn't really using bitplanes, but packed pixels).


> --------|	Rest assured that a walk through the ocean of most souls
> Alien   |   		would scarcely get your feet wet.	- Deteriorata
> --------|     decvax!frog!cpoint!alien      bu-cs!mirror!frog!cpoint!alien
-- 
Dave Haynie Commodore-Amiga (Systems Engineering) "The Crew That Never Rests"
   {uunet|pyramid|rutgers}!cbmvax!daveh      PLINK: hazy     BIX: hazy
                    Too much of everything is just enough