几何的本质就是运动.通常所说的所谓几何性质,其实质就是某个运动群的不变量.所以,利用运动——平移、旋转、反射等来解决几何问题,应该是本质的常用的方法.组合几何中的问题当然也不例外点的运动,生成点的轨迹(或者说是具有某种性质的点的集合),这是运动的结果.利用点运动做结果——点的轨迹(几何曲线、曲面)——作为工具解几何问题,也是我们处理组合几何问题的常用方法.运动事实上就是一个映射,例如平面上的运动就 The essence of geometry is motion. The so-called geometric properties are essentially the invariants of a motion group. Therefore, the use of motion—translation, rotation, reflection, etc. to solve geometric problems, should be a common and essential method. The problem in combinatorial geometry is of course no exception to the motion of the point, the trajectory of the generated point (or a collection of points of a certain nature), which is the result of the motion. Use the point motion to make the result - the trajectory of the point (geometric curve) , surface) - as a tool to solve geometric problems, is also a common method we deal with the problem of combinatorial geometry. Motion is in fact a map, such as the motion on the plane