private void setNewTarget() {
		if (mode == TEST) {
			// have the tank alternate between x=800 and x=200
			if (targetPlace == null)
				targetPlace = new Place(500, 500);
			else if (targetPlace.getX() < 500)
				targetPlace = new Place(800, 500);
			else
				targetPlace = new Place(200, 500);
		} else if (mode == RANDOM)
			targetPlace = heatMap.findRandomPlace();
		else if (mode == QUIET)
			targetPlace = heatMap.findQuietPlace();
		else
			targetPlace = heatMap.findMostCrowdedPlace();
	}