From: Shawn Hargreaves <Shawn AT talula DOT demon DOT co DOT uk>
Newsgroups: comp.os.msdos.djgpp
Subject: Re: Allegro --> virtual framerate
Date: Mon, 4 Aug 1997 19:18:35 +0100
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Marcus D. Brenneman writes:
>I think this revolves around a concept I call virtual framerate; the 
>engine updates the positions of everything, etc. at the same rate of 
>the highest possible framerate but only draws the frames it can. I want 
>to do this with my game and I'm not sure how to approach it.

You are thinking along the right lines here. Using Allegro, set up a
timer handler going at your fixed framerate, say 60 fps, and use it to
increment a global variable (eg. mycounter), which you initialise to
zero. Then write a control loop like:

    do {
        while (mycounter > 0) {
            move_objects(); 
            mycounter--;
        }

        redraw_screen();

    } while (!game_over);

It's that easy!


--
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.