public GameDefine.DirectionType GetOpenedDoorway(ChunkNode node)
        {
            if(node.Left != null)
            {
                return GameDefine.DirectionType.Left;
            }
            if(node.Right != null)
            {
                return GameDefine.DirectionType.Right;
            }
            if(node.Top != null)
            {
                return GameDefine.DirectionType.Top;
            }
            if(node.Bottom != null)
            {
                return GameDefine.DirectionType.Bottom;
            }

            Assert.IsTrue(false, "不正な値です.");
            return GameDefine.DirectionType.Left;
        }
 public ChunkDoorway(ChunkNode node)
 {
     flag = GetOpenedDoorway(node);
 }