Lines: 29
X-Admin: news AT aol DOT com
From: forkazoo2 AT aol DOT com (Will R)
Newsgroups: comp.os.msdos.djgpp
Date: 17 Jun 2001 03:18:11 GMT
References: <3B2C0FEE DOT 670D5EE7 AT mailandnews DOT com>
Organization: AOL http://www.aol.com
Subject: Re: So lemme get this straight
Message-ID: <20010616231811.14936.00001926@ng-mk1.aol.com>
To: djgpp AT delorie DOT com
DJ-Gateway: from newsgroup comp.os.msdos.djgpp
Reply-To: djgpp AT delorie DOT com

>
>32-bit mode is the same as 24-bit mode, but supposedly also contains an
>Alpha byte.
>8:8:8:8
>R:G:B:A
>
>I say supposedly, because I think some cards just ignore the 4th byte. 
>Still nice to use, though, even if the 4th byte doesn't work... a lot
>easier to format :)
>
>j.weeks
>

Actually, It's not an alpha channel in the context of video cards.  (OTOH, it
almost always is alpha in the context of 32 bit image files)  It is just done
because it is easier to format (as you said), and moving data in four byte
chunks is easier to do in the video hardware, as compared to three byte chunks.
 Thus, on some hardware, 32 bpp is a lot faster.

essentially, it is R:G:B:Nothing

Also, some video modes, and image files,  are GBR, BGR, etc, as opposed to
RGB...
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"We can write Planck's constant using the bytes 08 5C 2F C6 (hex).  We can use
these bytes as a (quantized!) 32-bit color. Multiplying RGB by A gives us a
hunter green."    -Ernie W (edited for space)
------------------
I am Will R.