To:	djgpp AT sun DOT soe DOT clarkson DOT edu, csaba AT vuse DOT vanderbilt DOT edu (Csaba A. Biegl)
Cc:	dridge AT MIT DOT EDU
Subject:	Re: Mach32 driver, Diamond Stealth
Date:	Tue, 22 Feb 94 10:12:06 EST
From:	Matthew Eldridge <dridge AT MIT DOT EDU>

>	Subject: Mach32 driver, Diamond Stealth
>	I'm going to start using DJGPP for simulating some 3D-graphics stuff.
>	I'm interested in getting high resolution/bit depth,
>	and want to be able to do at least 24bit color at 640x480,
>	preferably at 800x600.

>GO32 1.11's built-in VESA driver works with the Stealth. The only ATI ULTRA I
>have experience with is the original ULTRA from '92. At that time I was
>not very impressed with the VESA support in the ATI BIOS-es. (Their
>so-called VESA BIOS did not know about the higher resolution modes of
>the card.) The GRX drivers which use these cards in accelerated modes can
>only support 256 colors, for higher color depth you have to use 
>a "dumb frame" approach. The current GRX release only supports 16 bit
>color depth, but you >can use Gregory's VESA library for 24 bit color.
okay.... what/where is this 24 bit color stuff?  This is the only reference
I've seen to it since getting onto this list.

>If you want the best performance, you probably should not use any of the
>graphics libraries in your rendering code. Calling 'GrPlot' 1024x768 (or so)
>times can add quite a bit of overhead. Using GO32's linear VGA memory
>mapping you can quite easily inline your pixel set routine. (Of course
right, that is my intent.  What I am concerned about is whether GO32
will even be able to do a linear mapping on a ATI Ultra Pro in 24bit
mode.  I have a oddball Cirrus chipset in a notebook that it can't handle,
I'd just as soon not repeat that fiasco.

So, 2 questions:

1) what/where is the 24-bit library for doing DJGPP graphics
2) will DJGPP/GO32 be able to drive an ATI Ultra Pro in these great 24bit
   modes?

Feedback from anybody who has done what I'm getting ready to tackle will
be greatly appreciated.

-Matthew

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