From: castroto AT remus DOT rutgers DOT edu (Fabrizio Castrotorres)
Newsgroups: comp.os.msdos.djgpp
Subject: Re: sprites and ALLEGRO'S draw_sprite();
Date: 27 Jan 1998 14:28:28 -0500
Organization: Rutgers University LCSR
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Message-ID: <6alcgs$suh$1@remus.rutgers.edu>
References: <19980123161800 DOT LAA01145 AT ladder01 DOT news DOT aol DOT com>
NNTP-Posting-Host: remus.rutgers.edu
To: djgpp AT delorie DOT com
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pitel AT aol DOT com (Pitel) writes:

>Hello 

>Can someone help me, i am trying to display
>a sprite animation on a screen that i have place 
>a background bitmap image, but as i move the sprite
>the sprite destroyes the background (erases it).

>how can i save the background image and restore it 
>when the sprite has moved off that area.

>Thanks 

>Pitel AT aol DOT com
>Eric  

Or you can use double buffering,

1.- save the background that will be written over by the sprite to a buffer
    before you put the sprite on the screen.
2.- Blit sprite to screen
3.- restore previous background
4.- save new background....
5.- Blit sprite ...etc

All drawsprite does is make a certain pixels in your sprite transparent
so that that you can see background around the sprite, it does not do 
double buffering for you.

hope that helps