public class TestBlock {

        public Direction Facing {
            get {
                if (_facing[0] == false && _facing[1] == false)
                    return Direction.North;
                else if (_facing[0] == false && _facing[1] == true)
                    return Direction.East;
                else if (_facing[0] == true && _facing[1] == false)
                    return Direction.South;
                else
                    return Direction.West;
            }
        }

        BitArray _facing = new BitArray(2);
        BitArray _subType = new BitArray(4);
    }

    public enum Direction : byte {
        North = 0x00,
        East = 0x01,
        South = 0x02,
        West = 0x03
    }