Date: Tue, 14 Feb 1995 17:10:25 -0500 (CDT)
From: Aaron Ucko <UCKO AT VAX1 DOT ROCKHURST DOT EDU>
Subject: Re: Graphics and DPMI under Windoze
To: sandmann AT new-orleans DOT NeoSoft DOT com
Cc: djgpp AT sun DOT soe DOT clarkson DOT edu
Organization: Rockhurst College; Kansas City, MO

>so I can't enable the linear mode to even test it.  If your card and
>bus can agree on a linear address which is OK, then a linear buffer could
>be established and accessed via far pointers.  There are also tricks that
>can be used on *SOME* DPMI providers to access this with a simple 
>pointer, but it won't work everywhere.  So, this is the problem.  Some
>machines in some environments can get linear graphics, others can't.  If you 

Some graphics cards are frame buffers and others are accelerated.
Does that mean GRX shouldn't take advantage of acceleration if it
finds an accelerated card?  Then why can't it take advantage of
a linear buffer if it finds a card which supports one?

>In V2 do we want linear graphics bad enough to limit where the code to 
>run, or do you bite the bullet and deal with the page swapping and
>write code that will run under *ALL* environments?

Write the page swapping code as a backup; the driver tells the
library whether it can use linear addressing or has to resort
to page swapping.

--- Aaron Ucko (ucko AT vax1 DOT rockhurst DOT edu; finger for PGP public key) -=- httyp!
-=*=-Just because you're paranoid doesn't mean they aren't out to get you.-=*=-
Geek code 2.1 [finger hayden AT vax1 DOT mankato DOT msus DOT edu for explanation]: 
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