OpenMesh中如何利用CGAL提供的API定位距离给定点最近的面(不使用AABB tree)

关键代码核心逻辑

step 1 - 将OpenMesh:TriMesh的mesh转化为CGAL:Surface_mesh<Point_3>的mesh

step 2 - 将三个轴上的坐标转化成CGAL:Point

step 3 - 调用PMP::locate()

step 4 - CGAL:Face_location转化为OpenMesh:faceHandle

remark : 输入的是OpenMesh类型的mesh，输出的是OpenMesh类型的FaceHandle，在过程中用到了CGAL的mesh。

locateVertexInFace.cpp

#include <string>
#include <fstream>
#include <OpenMesh/Core/Mesh/DefaultTriMesh.hh>
#include <OpenMesh/Core/Mesh/PolyConnectivity.hh>
#include <CGAL/Exact_predicates_inexact_constructions_kernel.h>
#include <CGAL/Polyhedron_3.h>
#include <CGAL/Polygon_mesh_processing/locate.h>
#include <CGAL/boost/graph/copy_face_graph.h>
#include <CGAL/Surface_mesh.h>
#include "locateVertexInFace.h"

boost::unordered_map<tm_vertex_descriptor, pm_vertex_descriptor>        v2v;
boost::unordered_map<tm_halfedge_descriptor, pm_halfedge_descriptor>    h2h;
boost::unordered_map< tm_face_descriptor, pm_face_descriptor>           f2f;

FaceHandle locateVertexInFace(TriMesh& _OM_mesh, const double& _x, const double& _y, const double& _z) {

	

	//1. OpenMesh:TriMesh的mesh转化为CGAL:Surface_mesh<Point_3>的mesh
	PolyMesh CGAL_mesh;

	CGAL::copy_face_graph(_OM_mesh, CGAL_mesh,
		CGAL::parameters::vertex_to_vertex_map(boost::make_assoc_property_map(v2v)).
		halfedge_to_halfedge_output_iterator(std::inserter(h2h,h2h.end())).
		face_to_face_map(boost::make_assoc_property_map(f2f))
		);

	//2. 将三个轴上的坐标转化成CGAL:Point
	const Point_3 query(_x, _y, _z);

	//3. 调用PMP::locate()
	Face_location query_location = PMP::locate(query, CGAL_mesh);

	//4. CGAL:Face_location转化为OpenMesh:faceHandle
	FaceHandle faceHandle_(query_location.first);
	//std::clog << faceHandle_ << std::endl;

	return faceHandle_;
}

locateVertexInFace.h

#ifndef LOCATEVERTEXINFACE_H
#define LOCATEVERTEXINFACE_H

#include <OpenMesh/Core/Mesh/DefaultTriMesh.hh>
#include <OpenMesh/Core/Mesh/PolyConnectivity.hh>
#include <CGAL/Exact_predicates_inexact_constructions_kernel.h>
#include <CGAL/Polyhedron_3.h>
#include <CGAL/Polygon_mesh_processing/locate.h>
#include <CGAL/boost/graph/copy_face_graph.h>
#include <boost/unordered_map.hpp>
#include <CGAL/Surface_mesh.h>
#include <CGAL/boost/graph/graph_traits_TriMesh_ArrayKernelT.h>
#include <CGAL/boost/graph/graph_traits_PolyMesh_ArrayKernelT.h>

typedef OpenMesh::TriMesh TriMesh;
typedef TriMesh::FaceHandle FaceHandle;
typedef TriMesh::Point Point;

typedef CGAL::Exact_predicates_inexact_constructions_kernel  Kernel;
typedef Kernel::Point_3                                      Point_3;
typedef CGAL::Surface_mesh<Point_3>                          PolyMesh;

namespace PMP = CGAL::Polygon_mesh_processing;
typedef PMP::Face_location<PolyMesh, Kernel::FT>             Face_location;

typedef boost::graph_traits<TriMesh>::vertex_descriptor      tm_vertex_descriptor;
typedef boost::graph_traits<TriMesh>::halfedge_descriptor    tm_halfedge_descriptor;
typedef boost::graph_traits<TriMesh>::face_descriptor        tm_face_descriptor;

typedef boost::graph_traits<PolyMesh>::vertex_descriptor      pm_vertex_descriptor;
typedef boost::graph_traits<PolyMesh>::halfedge_descriptor    pm_halfedge_descriptor;
typedef boost::graph_traits<PolyMesh>::face_descriptor        pm_face_descriptor;



FaceHandle locateVertexInFace(TriMesh& mesh, const double& _x, const double& _y, const double& _z);

#endif

main.cpp

#include <iostream>
#include <OpenMesh/Core/IO/MeshIO.hh>
#include <OpenMesh/Core/Mesh/DefaultTriMesh.hh>
#include <OpenMesh/Core/Mesh/PolyConnectivity.hh>
#include "locateVertexInFace.h"

int main() {

	TriMesh mesh;

	//读入文件
	OpenMesh::IO::read_mesh(mesh, "E:\\3d_model_files\\1160382.off");

	locateVertexInFace(mesh, 289, 302, 98);


	return 0;
}