改成小写 ompl呢

那这个就只能都拓展了

@jasonchen 

ns存储：自然邻居

f1存储：会导致产生强制邻居的障碍物格子

f2存储：强制邻居

大家可以对应着这个注释

	// for each (dx,dy,dz) these contain:
	//    ns: neighbors that are always added
	//    f1: forced neighbors to check
	//    f2: neighbors to add if f1 is forced
	int ns[27][3][26];
	int f1[27][3][12];
	int f2[27][3][12];
	// nsz contains the number of neighbors for the four different types of moves:
	// no move (norm 0):        26 neighbors always added
	//                          0 forced neighbors to check (never happens)
	//                          0 neighbors to add if forced (never happens)
	// straight (norm 1):       1 neighbor always added
	//                          8 forced neighbors to check
	//                          8 neighbors to add if forced
	// diagonal (norm sqrt(2)): 3 neighbors always added
	//                          8 forced neighbors to check
	//                          12 neighbors to add if forced
	// diagonal (norm sqrt(3)): 7 neighbors always added
	//                          6 forced neighbors to check
	//                          12 neighbors to add if forced
	static constexpr int nsz[4][2] = {{26, 0}, {1, 8}, {3, 12}, {7, 12}};

至于这两个函数，就是具体指出哪一个格子是自然格子，哪一个是强制格子，哪一个格子出现障碍物会产生强制邻居

用来存储候选子节点到父节点的长度