From:	Shawn Hargreaves <Shawn AT talula DOT demon DOT co DOT uk>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: When you know Nothing!
Date:	Wed, 11 Jun 1997 20:16:42 +0100
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To:	djgpp AT delorie DOT com
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Guilherme Silveira writes:
>- When I use the page flipping with Allegro, can I use only Horizontal
>  flipping?

You can scroll in any direction, as long as your virtual screen is large
enough to allow it. The virtual screen size is specified as the last two
parameters to set_gfx_mode(), although it is obviously limited by the
amount of video memory, and on many VESA systems the width must be a
power of two. Also, many SVGA cards can only horizontally scroll in
increments of four or sometimes even eight pixels. 

Allegro considers page flipping to be a special case of scrolling, where
you are moving by the entire size of the screen, so it is entirely up to
you how you want to organise your video RAM.

>- Does anyone have some source code with page flipping that can send 
>  me?

Look at examples/ex9.c and demo.c for regular page flipping, and
examples/ex20.c for triple buffering.


--
Shawn Hargreaves - shawn AT talula DOT demon DOT co DOT uk - http://www.talula.demon.co.uk/
Beauty is a French phonetic corruption of a short cloth neck ornament.

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