通过Eigen的矩阵运算，将点云进行Z轴旋转45°，再沿X轴平移2.5.
pcl::PointCloud<pcl::PointXYZ>::Ptr source_cloud(new pcl::PointCloud<pcl::PointXYZ>());
pcl::PointCloud<pcl::PointXYZ>::Ptr transformed_cloud(new pcl::PointCloud<pcl::PointXYZ>());
float theta = M_PI / 4; // The angle of rotation in radians
Eigen::Affine3f transform_2 = Eigen::Affine3f::Identity();
// Define a translation of 2.5 meters on the x axis.
transform_2.translation() << 2.5, 0.0, 0.0;
// The same rotation matrix as before; theta radians around Z axis
transform_2.rotate(Eigen::AngleAxisf(theta, Eigen::Vector3f::UnitZ()));
// Print the transformation
printf("\nMethod #2: using an Affine3f\n");
std::cout << transform_2.matrix() << std::endl;
// Executing the transformation
// You can either apply transform_1 or transform_2; they are the same
pcl::transformPointCloud(*source_cloud, *transformed_cloud, transform_2);