From:	Hartmut Schirmer <hsc AT techfak DOT uni-kiel DOT de>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: Can I use 256 grayscale colors?
Date:	Mon, 16 Jun 1997 08:55:28 +0200
Organization:	Technische Fakultaet, University of Kiel, Germany
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Paul Szuch wrote:
> VGA limits you to 6bits/color so you can't get more than 2^6=64 shades
> of gray with VGA. If you want more you'll have to go to true-color
> which allows 8bits/color=24bits/pixel. Allegro is on the virge of
> allowing these modes as I recall. GRX20 only allows
> high-color(5-6bits/color) so I'm not sure about accessing a true-color
> mode. In any event it is very difficult to visually tell the
> difference between 64 levels of gray anyway.

Some cards have 8bit dacs. With VESA 2.0 there is a programming
interface to access these features.

Hartmut
-- 
Hartmut Schirmer                   | Phone: +49-431-77572-709  FAX:-703
Automatisierungs- & Regelungstech. | hsc AT techfak DOT uni-kiel DOT de
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