Open3D (C++) normal space sampling

I. Overview

  The main steps of normal space sampling are as follows:

1. Divide the point cloud according to the normal vector information of the point cloud bin;
2. Randomly uniform sampling is performed in each binuntil the number of sampling points meets the requirements. This article is a detailed process code reproduction using the C++ version of Open3D based on a
     full understanding of the PCL normal space sampling algorithm principle and source code.

2. Code implementation

#include <iostream>
#include<Open3D\Open3D.h>