public PositionDirection next(int gap) {
			PositionDirection newPd = null;
			int v = getValue() + gap;
			if (v > 12) {
				v %= 12;
			}
			switch (v) {
			case 6:
				newPd = CLOCK6;
				break;
			case 9:
				newPd = CLOCK9;
				break;
			case 12:
				newPd = CLOCK12;
				break;
			case 3:
			default:
				newPd = CLOCK3;
				break;
			}
			return newPd;			
		}