Path: utzoo!attcan!uunet!lll-winken!lll-tis!helios.ee.lbl.gov!pasteur!ucbvax!decwrl!labrea!polya!kaufman
From: kaufman@polya.Stanford.EDU (Marc T. Kaufman)
Newsgroups: comp.sys.mac.programmer
Subject: Re: 24bit QuickDraw
Keywords: QuickDraw
Message-ID: <3069@polya.Stanford.EDU>
Date: 17 Jun 88 15:58:06 GMT
References: <2183@munnari.oz>
Reply-To: kaufman@polya.Stanford.EDU (Marc T. Kaufman)
Organization: Stanford University
Lines: 20

In article <2183@munnari.oz> castan@munnari.oz (Jason Castan) writes:

>	What does the 24 bit QuickDraw mean?
>	Does that mean it uses 24 bits per R/G/B? 

Yes, actually 32 bits per pixel, with 8 bits each of R/G/B and 8 bits spare
for your use (Alpha, etc.).  There are two variations of 24-bit R/G/B defined
by Apple:  8-bits per pixel in separate R,G,B planes (chunky-planar), and
32-bits per pixel with R/G/B packed in (chunky).  Apple has announced that they
will ONLY support chunky format.  This has the side effect of restricting such
PixMaps to a maximum of 2047 pixel elements per row.

>	How does that differ from a 32bit graphics coprocessors which are soon
>	to be here.

a coprocessor just manipulates graphics data.  24-bit QuickDraw IS the data
format.  I don't know which coprocessors, if any, will be conformant to 24-bit
QD.

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Marc Kaufman (kaufman@polya.stanford.edu)