Path: utzoo!utgpu!news-server.csri.toronto.edu!rutgers!apple!claris!outpost.UUCP!peirce
From: peirce@outpost.UUCP (Michael Peirce)
Newsgroups: comp.sys.mac.misc
Subject: Re: 24-bit color
Message-ID: <b.APBIWW@outpost.UUCP>
Date: 5 Dec 90 16:36:35 GMT
Reply-To: peirce@outpost.UUCP
Organization: Peirce Software
Lines: 22
X-Mailer: uMail - Mac Release: 0.1.4


In article <6110@crash.cts.com>, bill@pro-gateway.cts.com (Bill Long, SysOp) writes:
> 
> I'm an Apple II user and try to somewhat keep up with the Mac world, and I
> have a couple of questions about 24-bit graphics.
> 
> 1) Why is 24-bit better than 32-bit?

24-bit isn't better than 32-bit.  32-bit color is 24-bit color plus 8-bits 
for an alpha channel.  Since Apple hasn't defined what the alpha channel
is suppose to do (though some third parties have), this extra 8-bits
of data isn't used by video cards.  Often these two terms are used 
interchangeably.  

 
> 2) How many of the 16 million colors can be on-screen at once?

With 24-bit color each pixel can fully specify a color (8 bits of
red, blue, & green) so you can display as many colors on the screen
as you have pixels.

-- michael


--  Michael Peirce         --   {apple,decwrl}!claris!outpost!peirce
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