Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!uunet!cbmvax!daveh
From: daveh@cbmvax.commodore.com (Dave Haynie)
Newsgroups: comp.sys.amiga.hardware
Subject: Re: Cost of color (was: Bitplanes - good or bad)
Keywords: writing a pixel
Message-ID: <10724@cbmvax.commodore.com>
Date: 9 Apr 90 20:44:14 GMT
References: <5917@tekig5.PEN.TEK.COM> <1990Mar31.092753.203@actrix.co.nz> <10581@cbmvax.commodore.com> <5975@tekig5.PEN.TEK.COM>
Reply-To: daveh@cbmvax (Dave Haynie)
Organization: Commodore, West Chester, PA
Lines: 41

In article <5975@tekig5.PEN.TEK.COM> wayneck@tekig5.PEN.TEK.COM (Wayne C Knapp) writes:
>In article <10581@cbmvax.commodore.com>, mks@cbmvax.commodore.com (Michael Sinz - CATS) writes:

>It wouldn't be for everyone, that's for sure.  However, I think that the
>fact that it isn't easy to do on the Amiga does hurt the Amiga's image.
>Having a card like the Hercules card that ran with the Amiga wouldn't 
>hurt Amiga sales.  Plus, if it didn't require a bridge board and supported
>intuition it would be economical and very attractive to Amiga developers. 

The problem isn't the hardware; such a card would at least as easy to design
for the Amiga bus.  The problem is the software, and the question of where the
software display intelligence resides.  In most of the MS-DOS world today (of
course I know this is changing, however slowly, with things like Windows and
TIGA) the intelligence for driving a particular graphics card is contained in 
each application program.  Each program must implement it's own graphics, 
window, etc. drivers.  That's kind of evil, but it does make the choice of 
support for graphics cards up to the program designer.	It's also why most of 
the cool graphics hardware contains hardware or firmware emulations of some
of the lesser graphics systems on the market.  

The Amiga, on the other hand, implements a graphics library which contains 
most of the display intelligence for any application program.  Ideally, all
the device dependent graphics operations would go through graphics, and I
suppose at some point they will.  There are a considerable number of calls
in the graphics library, far more than any simple MS-DOS based application
would use it its program-resident graphics driver.  Which currently makes 
it a real piece of work for any company to build a graphics board that can
run the average Amiga program.  Nothing's stoping anyone from taking the
MS-DOS approach (board-specific program knowledge) or the Mac approach
(a new graphics kernel replacement for add-on boards).  It's just alot of
work, and apparently things like Intuition aren't completely pure; on
occasion they do things on their own, instead of going through graphics
library.

>                                         Wayne Knapp


-- 
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