view docs/html/guidetimeexamples.html @ 2197:2ff40f30af31

Merged r3261:3262 from branches/SDL-1.2: MMX/YUV with __OPTIMIZE__. "Mac OS X/x86 won't build the MMX/YUV inline assembly without optimizations enabled (not enough registers), so for now, we only build it if we see the __OPTIMIZE__ #define, which GCC provides when you build at -O1 or higher."
author Ryan C. Gordon <icculus@icculus.org>
date Sat, 14 Jul 2007 07:28:45 +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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