在3D空间选择感兴趣的空间点，以便后期处理，如seed 点。-Choice in the 3D space of the spatial point of interest in order to deal with the latter, such as seed points.

设三个已知点，通过目标点到已知点的距离，求目标点在已知点所在的空间坐标系中的坐标值，用来定义一个任意空间中所有兴趣点的空间关系-Have three known points a known point by point to the target, find the target point coordinates at a known point where the spatial coordinate system used to define a spatial relationshi