From:	Joseph Morris <jpm AT it-he DOT org>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: svga
Date:	Sun, 04 Jun 2000 18:56:55 +0100
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Message-ID:	<393A9867.8872DAEE@it-he.org>
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To:	djgpp AT delorie DOT com
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Martell wrote:
> 
> i already know how to get into svga mode (640x480x256 ... 5 banks) using
> DJGPP, but i want to know how to have a buffer for the screen (307,200
> bytes) so it would work like this:
> 1) i would draw to the 307,200 buffer
> 2) during retrace i would draw 64K to the first bank, switch banks, draw
> the next 64K, etc until the entire buffer had been transfered to the
> screen.
> 
> i tried to create a program that did this, using a near pointer to the
> screen, but after it finished drawing to the first bank, it restarted my
> computer.   any suggestions?

Yes.  Try either of these:

1. Use an intermediate library like Allegro to do the work for you.
It will save you time in the long run, and makes porting to Linux and
Windows easier.

2. If you must do it your way, try and use a linear framebuffer instead
of banking, it makes life so much easier.


-- 
JP Morris - aka DOUG the Eagle (Dragon) -=UDIC=-  doug AT it-he DOT org
Fun things to do with the Ultima games            (http://www.it-he.org)
Developing a U6/U7 clone                          (http://fly.to/ire)
d+++ e+ N+ T++ Om U1234!56!7'!S'!8!9!KA u++ uC+++ uF+++ uG---- uLB----
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