Message-ID: <377AB6AA.3F73B59D@unb.ca>
From: Endlisnis <s257m AT unb DOT ca>
Organization: Nortel Networks
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Newsgroups: comp.os.msdos.djgpp
Subject: Re: Scrolling in SVGA
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Date: Thu, 01 Jul 1999 00:29:53 GMT
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To: djgpp AT delorie DOT com
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Reply-To: djgpp AT delorie DOT com

Sahab Yazdani wrote:

> I needs lot of help with this one.  Even with Assembly functions for
> Drawing stuff, my scrolling routine is slow in 640X480.  it works fine
> in 320X200 (although hardware scrolling in mode X is still faster).  but
> with SVGA modes it just bombs out!  Can anybody help me with some SVGA
> scrolling routines?  Possibly a site or tutorial that references these
> things??

    Well, if you have enough ram, you can do hardware scrolling in SVGA.
Also, something I've observed, in SVGA modes, it is usually MUCH faster to
redraw the entire screen from a memory buffer than to do real scrolling
because reading from video ram is sometimes up to 10 times slower than
writing.


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