view docs/html/guidetimeexamples.html @ 3164:c5b2884c26b4

Added an ifdef so that if you #define SDL_NO_COMPAT before you include SDL.h then SDL_compat.h will never be included in your code. This is useful for making sure that your code uses only SDL 1.3 features. It is also handy for finding things that are in SDL_compat.h that belong elsewhere.
author Bob Pendleton <bob@pendleton.com>
date Thu, 04 Jun 2009 21:00:45 +0000
parents 355632dca928
children
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>Time Examples</H1
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>Time based game loop</H2
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>#define TICK_INTERVAL    30

static Uint32 next_time;

Uint32 time_left(void)
{
    Uint32 now;

    now = SDL_GetTicks();
    if(next_time &#60;= now)
        return 0;
    else
        return next_time - now;
}


/* main game loop */

    next_time = SDL_GetTicks() + TICK_INTERVAL;
    while ( game_running ) {
        update_game_state();
        SDL_Delay(time_left());
        next_time += TICK_INTERVAL;
    }&#13;</PRE
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