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  78 >Time Examples</H1
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  88 >Time based game loop</H2
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  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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