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Mail Archives: djgpp/1997/08/07/11:06:22

From: Jonathon Ralston <j DOT ralston AT cat DOT csiro DOT au>
Newsgroups: comp.os.msdos.djgpp
Subject: [Q]: Horizontal scrolling using Allegro
Date: Thu, 07 Aug 1997 13:58:17 +1000
Organization: CSIRO
Lines: 19
Message-ID: <33E947D9.28C0@cat.csiro.au>
Reply-To: j DOT ralston AT cat, csiro DOT au AT delorie DOT com
NNTP-Posting-Host: mcfly.cat.csiro.au
Mime-Version: 1.0
CC: ralston AT delorie DOT com
To: djgpp AT delorie DOT com
DJ-Gateway: from newsgroup comp.os.msdos.djgpp

Hello,

I wanted to write a horizontal scrolling program using allegro in 640 x
480 x 256 resolution. Using ex19.c as a base, I increased the screen
bitmap size and changed the other screen size variables accordingly. 
However, I found that *everything* on the screen was scrolled, including
the text line.

Is it possible to scroll only *part* of the screen while in an SVGA
mode, e.g., a 640 x 400 window?  I noticed that in ex19.c you used a
mode X modex_split function.  Does this mean that the split screen
text/scrolling only exists in mode X?  Is there a version of
scroll_screen() that scrolls only part of the screen, or a BITMAP
buffer?

Any pointers would be greatly appreciated.

Jonathon.
j DOT ralston AT cat DOT csiro DOT au

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