\( \newcommand{\E}{\mathrm{E}} \) \( \newcommand{\A}{\mathrm{A}} \) \( \newcommand{\R}{\mathrm{R}} \) \( \newcommand{\N}{\mathrm{N}} \) \( \newcommand{\Q}{\mathrm{Q}} \) \( \newcommand{\Z}{\mathrm{Z}} \) \( \def\ccSum #1#2#3{ \sum_{#1}^{#2}{#3} } \def\ccProd #1#2#3{ \sum_{#1}^{#2}{#3} }\)
CGAL 5.0.1 - Polygon Mesh Processing
Polygon_mesh_processing/repair_polygon_soup_example.cpp
#include <CGAL/Exact_predicates_inexact_constructions_kernel.h>
#include <CGAL/Surface_mesh.h>
#include <CGAL/Polygon_mesh_processing/repair_polygon_soup.h>
#include <CGAL/Polygon_mesh_processing/orient_polygon_soup.h>
#include <CGAL/Polygon_mesh_processing/polygon_soup_to_polygon_mesh.h>
#include <iostream>
#include <vector>
typedef K::Point_3 Point_3;
typedef std::vector<std::size_t> Polygon;
int main(int, char**)
{
// First, construct a polygon soup with some problems
std::vector<Point_3> points;
std::vector<Polygon> polygons;
points.push_back(Point_3(0,0,0));
points.push_back(Point_3(1,0,0));
points.push_back(Point_3(0,1,0));
points.push_back(Point_3(-1,0,0));
points.push_back(Point_3(0,-1,0));
points.push_back(Point_3(0,1,0)); // duplicate point
points.push_back(Point_3(0,-2,0)); // unused point
Polygon p;
p.push_back(0); p.push_back(1); p.push_back(2);
polygons.push_back(p);
// degenerate face
p.clear();
p.push_back(0); p.push_back(0); p.push_back(0);
polygons.push_back(p);
p.clear();
p.push_back(0); p.push_back(1); p.push_back(4);
polygons.push_back(p);
// duplicate face with different orientation
p.clear();
p.push_back(0); p.push_back(4); p.push_back(1);
polygons.push_back(p);
p.clear();
p.push_back(0); p.push_back(3); p.push_back(5);
polygons.push_back(p);
// degenerate face
p.clear();
p.push_back(0); p.push_back(3); p.push_back(0);
polygons.push_back(p);
p.clear();
p.push_back(0); p.push_back(3); p.push_back(4);
polygons.push_back(p);
// pinched and degenerate face
p.clear();
p.push_back(0); p.push_back(1); p.push_back(2); p.push_back(3);
p.push_back(4); p.push_back(3); p.push_back(2); p.push_back(1);
polygons.push_back(p);
PMP::repair_polygon_soup(points, polygons);
PMP::orient_polygon_soup(points, polygons);
Mesh mesh;
PMP::polygon_soup_to_polygon_mesh(points, polygons, mesh);
std::cout << "Mesh has " << num_vertices(mesh) << " vertices and " << num_faces(mesh) << " faces" << std::endl;
assert(num_vertices(mesh) == 5);
assert(num_faces(mesh) == 4);
return 0;
}