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     78 >Time Examples</H1
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     88 >Time based game loop</H2
     89 ><P
     90 ><PRE
     91 CLASS="PROGRAMLISTING"
     92 >#define TICK_INTERVAL    30
     93 
     94 static Uint32 next_time;
     95 
     96 Uint32 time_left(void)
     97 {
     98     Uint32 now;
     99 
    100     now = SDL_GetTicks();
    101     if(next_time &#60;= now)
    102         return 0;
    103     else
    104         return next_time - now;
    105 }
    106 
    107 
    108 /* main game loop */
    109 
    110     next_time = SDL_GetTicks() + TICK_INTERVAL;
    111     while ( game_running ) {
    112         update_game_state();
    113         SDL_Delay(time_left());
    114         next_time += TICK_INTERVAL;
    115     }&#13;</PRE
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