private static int currentFPS = 0;
   public static int Fps; //Actual frames per second
   private static long start = 0;
   public static int levelTime = 120; //120 seconds = 2 minutes

   public static void updateFps() {
      currentFPS++;
      if (System.currentTimeMillis() - start >= 1000) { 
         levelTime -= 1; //We deduct 1 second, every second.
         Fps = currentFPS;
         currentFPS = 0;
         start = System.currentTimeMillis();
      }
   }