CGAL点云区域生长代码

以下是一个使用CGAL库的点云区域生长算法的示例代码：

#include <iostream>
#include <vector>
#include <CGAL/Exact_predicates_inexact_constructions_kernel.h>
#include <CGAL/Point_set_3.h>
#include <CGAL/property_map.h>
#include <CGAL/Point_set_3/Point_set_processing_3.h>

typedef CGAL::Exact_predicates_inexact_constructions_kernel Kernel;
typedef Kernel::FT FT;
typedef Kernel::Point_3 Point;
typedef CGAL::Point_set_3<Point> Point_set;

int main()
{
    // 读取点云数据
    Point_set points;
    std::ifstream stream("point_cloud.xyz");
    if (!stream ||
        !CGAL::read_xyz_points(stream, std::back_inserter(points))) {
        std::cerr << "Error: cannot read file point_cloud.xyz" << std::endl;
        return 1;
    }

    // 定义区域生长算法参数
    std::vector<std::size_t> region;
    std::vector<Point> seeds;
    CGAL::parameters::PointPmap<Point_set> point_pmap(points);
    CGAL::parameters::NormalPmap<Point_set> normal_pmap(points);
    CGAL::parameters::SeedMap<std::vector<Point>::const_iterator> seed_map(seeds.begin(), seeds.end());
    CGAL::parameters::KsearchParams k_params(10);
    CGAL::parameters::RegionGrowing::Parameters<Kernel> parameters(0.1 /*angle threshold*/,
                                                                   0.5 /*radius threshold*/,
                                                                   100 /*minimum cluster size*/,
                                                                   10000 /*maximum number of neighbors to consider*/,
                                                                   10 /*number of threads*/,
                                                                   point_pmap /*point property map*/,
                                                                   normal_pmap /*normal property map*/,
                                                                   seed_map /*seed property map*/,
                                                                   k_params /*k search parameters*/);

    // 执行区域生长算法
    CGAL::cpp11::result_of<CGAL::Point_set_processing_3::Region_growing<Point_set>::type>::type
        region_growing = CGAL::region_growing<Point_set>(points, parameters);

    // 输出结果
    std::cout << "Number of clusters: " << region_growing.size() << std::endl;
    for (std::size_t i = 0; i < region_growing.size(); ++i) {
        std::cout << "Cluster " << i << " size: " << region_growing[i].size() << std::endl;
    }

    return 0;
}

这里的输入点云数据需要以 .xyz 格式存储，每行包含一个点的 x、y、z 坐标。区域生长算法的具体参数可以根据需要进行调整。