public void findNextPositions() {
	Position next = currentPosition.topLeft();
	while(next.valid()) {
	    addNextPosition(next);
	    next = next.topLeft();
	}
	next = currentPosition.topRight();
	while(next.valid()) {
	    addNextPosition(next);
	    next = next.topRight();
	}
	next = currentPosition.bottomRight();
	while(next.valid()) {
	    addNextPosition(next);
	    next = next.bottomRight();
	}	
	next = currentPosition.bottomLeft();
	while(next.valid()) {
	    addNextPosition(next);
	    next = next.bottomLeft();
	}
    }