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From: grobbins@grad1.cis.upenn.edu (Grobbins)
Newsgroups: comp.sys.atari.st
Subject: Re: Atari's blitter vs. the Mac RISC graphics unit
Message-ID: <22073@netnews.upenn.edu>
Date: 23 Mar 90 06:48:35 GMT
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To clear up a couple of misconceptions:

- Apple's AMD 29K-based Quickdraw acceleration has been in development
  for years.  It was built not in response to market pressure, but
  because 24-bit graphics will soon be (more or less) standard on high-end
  Macs, and the performance of the machine is greatly degraded if the
  CPU has to do all of the drawing on 24 bit planes.

- Apple hasn't sped up Mac drawing with hardware before now because the
  Mac was never much of an animation engine to begin with.  With most
  Macs sporting a small monochrome display, there was little incentive
  to dedicate hardware to the task.

- The /real/ reason the Mac has lacked hardware graphics acceleration is
  that Quickdraw supports some unusual graphics primitives, mainly regions.
  No graphics chips exist which handle Quickdraw regions, so the benefit
  for the Mac would have been much less than for other computers whose OS's 
  used typical primitives like rectangles, ovals, and sprites.

Grobbins     grobbins@eniac.seas.upenn.edu