view docs/html/guidetimeexamples.html @ 4249:429c8dd3175d SDL-1.2

Fixed bug #713 Don't clamp the mouse coordinates to the video surface size, instead clamp them to the last known window size. This allows users to get the correct mouse coordinates even if they don't call SDL_SetVideoMode() in response to an SDL_VIDEORESIZE event (used as a hack to retain the OpenGL context on Windows and Linux after a window resize)
author Sam Lantinga <slouken@libsdl.org>
date Sun, 27 Sep 2009 05:18:43 +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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