PCL学习Day6

法向量计算

// 表面法向量
#include<pcl/io/pcd_io.h>
#include<pcl/point_types.h>
// 包含相关头文件
#include<pcl/features/normal_3d.h>
#include<pcl/visualization/pcl_visualizer.h>

typedef pcl::PointXYZ PointT;
typedef pcl::PointNormal PointNT;

int main() {
    
    
	// 读取点云
	pcl::PointCloud<PointT>::Ptr cloud(new pcl::PointCloud<PointT>);
	pcl::io::loadPCDFile("rabbit.pcd", *cloud);
	// 计算法向量
	pcl::NormalEstimation<PointT, PointNT> nest;
	nest.setKSearch(50);//设置拟合时采用的点数
	nest.setInputCloud(cloud);
	pcl::PointCloud<PointNT>::Ptr normals(new pcl::PointCloud<PointNT>);
	nest.compute(*normals);
	for (size_t i = 0; i < cloud->size(); i++)
	{
    
    
		// 生成时只生成了法向量，没有将原始点云信息拷贝，为了显示需要复制原信息
		normals->points[i].x = cloud->points[i].x;
		normals->points[i].y = cloud->points[i].y;
		normals->points[i].z = cloud->points[i].z;
	}
	//显示
	pcl::visualization::PCLVisualizer viewer;
	viewer.setBackgroundColor(0, 0, 0);

	viewer.addPointCloud(cloud, "cloud");
	int level = 100; // 多少条法向量集合显示成一条
	float scale = 1; // 法向量长度
	//pcl::visualization::PointCloudColorHandlerGenericField<pcl::PointXYZ> fildColor(cloud, "z");

	viewer.addPointCloudNormals<PointNT>(normals, level, scale, "normals");

	pcl::visualization::PointCloudColorHandlerGenericField<pcl::PointXYZ> fildColor(cloud, "z");//按照z字段进行渲染
	viewer.addPointCloud<pcl::PointXYZ>(cloud, fildColor, "sample");//显示点云，其中fildColor为颜色显示
	viewer.setPointCloudRenderingProperties(pcl::visualization::PCL_VISUALIZER_POINT_SIZE, 3, "sample");//设置点云大小
	viewer.spin();

	system("pause");
	return 0;
}

参考链接：https://github.com/MNewBie/PCL-Notes/blob/master/chapter2.md

https://zhuanlan.zhihu.com/p/268524083