> For the complete documentation index, see [llms.txt](https://pcl.gitbook.io/tutorial/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://pcl.gitbook.io/tutorial/part-2/part02-chapter06/part02-chapter06-triangulation-pcl-cpp.md).

# Triangulation-PCL-Cpp  (70%)

> 코드는 [\[이곳\]](https://github.com/adioshun/gitBook_Tutorial_PCL/blob/master/Intermediate/Part02-Chapter06-Triangulation-PCL-Cpp.cpp)에서 다운로드 가능합니다. 샘플파일은 [\[bunny.pcd\]](https://raw.githubusercontent.com/adioshun/gitBook_Tutorial_PCL/master/Intermediate/sample/bunny.pcd)을 사용하였습니다.

```cpp
#include <pcl/io/pcd_io.h>
#include <pcl/features/normal_3d.h>
#include <pcl/surface/gp3.h>
#include <pcl/io/vtk_io.h>

int
main(int argc, char** argv)
{
    // Object for storing the point cloud.
    pcl::PointCloud<pcl::PointXYZ>::Ptr cloud(new pcl::PointCloud<pcl::PointXYZ>);
    // Object for storing the normals.
    pcl::PointCloud<pcl::Normal>::Ptr normals(new pcl::PointCloud<pcl::Normal>);
    // Object for storing both the points and the normals.
    pcl::PointCloud<pcl::PointNormal>::Ptr cloudNormals(new pcl::PointCloud<pcl::PointNormal>);

    // Read a PCD file from disk.
    pcl::io::loadPCDFile<pcl::PointXYZ>("bunny.pcd", *cloud);


    // Normal estimation.
    pcl::NormalEstimation<pcl::PointXYZ, pcl::Normal> normalEstimation;
    normalEstimation.setInputCloud(cloud);
    normalEstimation.setRadiusSearch(0.03);
    pcl::search::KdTree<pcl::PointXYZ>::Ptr kdtree(new pcl::search::KdTree<pcl::PointXYZ>);
    normalEstimation.setSearchMethod(kdtree);
    normalEstimation.compute(*normals);

    // The triangulation object requires the points and normals to be stored in the same structure.
    pcl::concatenateFields(*cloud, *normals, *cloudNormals);
    // Tree object for searches in this new object.
    pcl::search::KdTree<pcl::PointNormal>::Ptr kdtree2(new pcl::search::KdTree<pcl::PointNormal>);
    kdtree2->setInputCloud(cloudNormals);

    // Triangulation object.
    pcl::GreedyProjectionTriangulation<pcl::PointNormal> triangulation;
    // Output object, containing the mesh.
    pcl::PolygonMesh triangles;
    // Maximum distance between connected points (maximum edge length).
    triangulation.setSearchRadius(0.025);
    // Maximum acceptable distance for a point to be considered,
    // relative to the distance of the nearest point.
    triangulation.setMu(2.5);
    // How many neighbors are searched for.
    triangulation.setMaximumNearestNeighbors(100);
    // Points will not be connected to the current point
    // if their normals deviate more than the specified angle.
    triangulation.setMaximumSurfaceAngle(M_PI / 4); // 45 degrees.
    // If false, the direction of normals will not be taken into account
    // when computing the angle between them.
    triangulation.setNormalConsistency(false);
    // Minimum and maximum angle there can be in a triangle.
    // The first is not guaranteed, the second is.
    triangulation.setMinimumAngle(M_PI / 18); // 10 degrees.
    triangulation.setMaximumAngle(2 * M_PI / 3); // 120 degrees.

    // Triangulate the cloud.
    triangulation.setInputCloud(cloudNormals);
    triangulation.setSearchMethod(kdtree2);
    triangulation.reconstruct(triangles);

    // Save to disk.
    pcl::io::saveVTKFile("bunny-mesh.vtk", triangles);
}
```

| ![](https://i.imgur.com/WPJsXa7.png) | ![](https://i.imgur.com/sWcWPMW.png) |
| ------------------------------------ | ------------------------------------ |
| 원본                                   | 결                                    |