实现环境：
pcl1.8.0+vs2015+win10
#include <vtkAutoInit.h>
VTK_MODULE_INIT(vtkRenderingOpenGL);
VTK_MODULE_INIT(vtkInteractionStyle);
VTK_MODULE_INIT(vtkRenderingFreeType);
#include <string>
#include <iostream>
#include <pcl/io/io.h>
#include <pcl/io/pcd_io.h>
#include <pcl/point_cloud.h>
#include <pcl/point_types.h>
#include <vector>
#include <pcl/visualization/pcl_visualizer.h>
#include <Eigen/Core>
#include <pcl/common/transforms.h>
using namespace std;
typedef pcl::PointXYZ PointType;
typedef pcl::Normal NormalType;
int main(int argc,char **argv)
{
pcl::PointCloud<PointType>::Ptr cloud(new pcl::PointCloud<PointType>());
pcl::PointCloud<NormalType>::Ptr cloud_normal(new pcl::PointCloud<NormalType>());
std::string fileName(argv[1]);
pcl::io::loadPCDFile(fileName, *cloud);
Eigen::Vector4f pcaCentroid;
pcl::compute3DCentroid(*cloud, pcaCentroid);
Eigen::Matrix3f covariance;
pcl::computeCovarianceMatrixNormalized(*cloud, pcaCentroid, covariance);
Eigen::SelfAdjointEigenSolver<Eigen::Matrix3f> eigen_solver(covariance, Eigen::ComputeEigenvectors);
Eigen::Matrix3f eigenVectorsPCA = eigen_solver.eigenvectors();
Eigen::Vector3f eigenValuesPCA = eigen_solver.eigenvalues();
//eigenVectorsPCA.col(2) = eigenVectorsPCA.col(0).cross(eigenVectorsPCA.col(1));
Eigen::Matrix4f transform(Eigen::Matrix4f::Identity());
transform.block<3, 3>(0, 0) = eigenVectorsPCA.transpose();
transform.block<3, 1>(0, 3) = -1.0f * (transform.block<3,3>(0,0)) * (pcaCentroid.head<3>());//
pcl::PointCloud<PointType>::Ptr transformedCloud(new pcl::PointCloud<PointType>);
pcl::transformPointCloud(*cloud, *transformedCloud, transform);
std::cout << eigenValuesPCA << std::endl;
std::cout << eigenVectorsPCA << std::endl;
//转换到原点时的主方向
PointType o;
o.x = 0.0;
o.y = 0.0;
o.z = 0.0;
Eigen::Affine3f tra_aff(transform);
Eigen::Vector3f pz = eigenVectorsPCA.col(0);
Eigen::Vector3f py = eigenVectorsPCA.col(1);
Eigen::Vector3f px = eigenVectorsPCA.col(2);
pcl::transformVector(pz, pz, tra_aff);
pcl::transformVector(py, py, tra_aff);
pcl::transformVector(px, px, tra_aff);
PointType pcaZ;
pcaZ.x = 1000 * pz(0);
pcaZ.y = 1000 * pz(1);
pcaZ.z = 1000 * pz(2);
PointType pcaY;
pcaY.x = 1000 * py(0);
pcaY.y = 1000 * py(1);
pcaY.z = 1000 * py(2);
PointType pcaX;
pcaX.x = 1000 * px(0);
pcaX.y = 1000 * px(1);
pcaX.z = 1000 * px(2);
//初始位置时的主方向
PointType c;
c.x = pcaCentroid(0);
c.y = pcaCentroid(1);
c.z = pcaCentroid(2);
PointType pcZ;
pcZ.x = 1000 * eigenVectorsPCA(0, 0) + c.x;
pcZ.y = 1000 * eigenVectorsPCA(1, 0) + c.y;
pcZ.z = 1000 * eigenVectorsPCA(2, 0) + c.z;
PointType pcY;
pcY.x = 1000 * eigenVectorsPCA(0, 1) + c.x;
pcY.y = 1000 * eigenVectorsPCA(1, 1) + c.y;
pcY.z = 1000 * eigenVectorsPCA(2, 1) + c.z;
PointType pcX;
pcX.x = 1000 * eigenVectorsPCA(0, 2) + c.x;
pcX.y = 1000 * eigenVectorsPCA(1, 2) + c.y;
pcX.z = 1000 * eigenVectorsPCA(2, 2) + c.z;
//visualization
pcl::visualization::PCLVisualizer viewer;
pcl::visualization::PointCloudColorHandlerCustom<PointType> color_handler(cloud,255, 0, 0);
pcl::visualization::PointCloudColorHandlerCustom<PointType> tc_handler(transformedCloud, 0, 255, 0);
viewer.addPointCloud(cloud,color_handler,"cloud");
viewer.addPointCloud(transformedCloud,tc_handler,"transformCloud");
viewer.addArrow(pcaZ, o, 0.0, 0.0, 1.0, false, "arrow_Z");
viewer.addArrow(pcaY, o, 0.0, 1.0, 0.0, false, "arrow_Y");
viewer.addArrow(pcaX, o, 1.0, 0.0, 0.0, false, "arrow_X");
viewer.addArrow(pcZ, c, 0.0, 0.0, 1.0, false, "arrow_z");
viewer.addArrow(pcY, c, 0.0, 1.0, 0.0, false, "arrow_y");
viewer.addArrow(pcX, c, 1.0, 0.0, 0.0, false, "arrow_x");
viewer.addCoordinateSystem(100);
viewer.setBackgroundColor(1.0, 1.0, 1.0);
while (!viewer.wasStopped())
{
viewer.spinOnce(100);
}
return 0;
}
