view docs/html/guidetimeexamples.html @ 1795:398ac0f88e4d

Fixed bug #220 The AltiVec blitters don't compile, since they require __VEC__ to be enabled in order for the compiler to understand "vector" and friends (i.e. do AltiVec) But you don't want to turn AltiVec on globally, since then the code would only run on a G4 (there are already runtime tests, before using the AltiVec variants) The solution here is to enable AltiVec locally, for the actual AltiVec code.
author Sam Lantinga <slouken@libsdl.org>
date Tue, 09 May 2006 15:09:47 +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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