To: csaba AT vuse DOT vanderbilt DOT edu (Csaba A. Biegl)
Cc: dridge AT MIT DOT EDU, djgpp AT sun DOT soe DOT clarkson DOT edu
Subject: Re: Mach32 driver, Diamond Stealth 
Date: Thu, 17 Feb 94 23:09:17 EST
From: Matthew Eldridge <dridge AT MIT DOT EDU>

>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
hmmm.  I talked to Gateway (the company I am looking at dealing with for
a new machine) and they weren't able to tell me anything.  Anyone out
there have the straight info?  I don't really want the filtered version from
ATI.

>color depth, but you >can use Gregory's VESA library for 24 bit color.
I heard somebody mention it, where/what is this?

>If your 3D graphics goes beyond a simple wire-frame or flat polygon
>approach (i.e. Goraud shading, ray tracing, etc..) then you don't need
>an accelerated card. Your program will have to calculate and display
>every pixel individually. In this case what you are looking for is a
it's a simulator for a chipset, so it is definitely doing the pixels
one by one.

>card with the fastest bus interface. Many times accelerated cards are in
>fact slower than simple "dumb frame" SVGA cards (i.e. ET4000, etc..)
what kind of card has an ET4000, etc. in it?
I am primarily concerned with 24bit color, at up to at least 640x480,
very preferably up to 800x600.

>with regard to direct video memory access from the CPU. A few months ago
>DJ circulated a video RAM access speed benchmark program and asked the
>readers of the group to run it on their systems. Check the archives of
>the mail group for the results.
where are these available?

>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
>you cannot run >under DPMI.) If you want to use 24 bit color, you also
>may want to look for a card which pads the pixels to 32 bits. (It is
>much faster to write a single long than three bytes.) One way to find
Will I be able to drop the card into a 24-bit mode, hopefully with
all 3 bytes contiguous (or padded to 4 bytes), and just blast across?
Will DJGPP/GO32 be able to handle it, or will I have to write my own
drivers, etc.?

Matthew Eldridge
dridge AT athena DOT mit DOT edu