用vc实现点云文件的加载和显示后，（dxf格式） 如何实现其中一些点的选取和删除的功能， 有没有类似的原代码发我一个，谢谢！-with vc achieve Cloud document loading and after the show, (dxf format) how to achieve some point select and delete functions, there are similar to the original code, I made a, th