CGAL 5.1.2 - Polygon Mesh Processing
Polygon_mesh_processing/hole_filling_example_SM.cpp
#include <CGAL/Exact_predicates_inexact_constructions_kernel.h>
#include <CGAL/Surface_mesh.h>
#include <CGAL/Polygon_mesh_processing/triangulate_hole.h>
#include <CGAL/Polygon_mesh_processing/border.h>
#include <boost/lexical_cast.hpp>
#include <iostream>
#include <fstream>
#include <vector>
#include <set>
typedef Kernel::Point_3 Point;
typedef boost::graph_traits<Mesh>::halfedge_descriptor halfedge_descriptor;
typedef boost::graph_traits<Mesh>::face_descriptor face_descriptor;
typedef boost::graph_traits<Mesh>::vertex_descriptor vertex_descriptor;
bool is_small_hole(halfedge_descriptor h, Mesh & mesh,
double max_hole_diam, int max_num_hole_edges)
{
int num_hole_edges = 0;
CGAL::Bbox_3 hole_bbox;
for (halfedge_descriptor hc : CGAL::halfedges_around_face(h, mesh))
{
const Point& p = mesh.point(target(hc, mesh));
hole_bbox += p.bbox();
++num_hole_edges;
// Exit early, to avoid unnecessary traversal of large holes
if (num_hole_edges > max_num_hole_edges) return false;
if (hole_bbox.xmax() - hole_bbox.xmin() > max_hole_diam) return false;
if (hole_bbox.ymax() - hole_bbox.ymin() > max_hole_diam) return false;
if (hole_bbox.zmax() - hole_bbox.zmin() > max_hole_diam) return false;
}
return true;
}
// Incrementally fill the holes that are no larger than given diameter
// and with no more than a given number of edges (if specified).
int main(int argc, char* argv[])
{
const char* filename = (argc > 1) ? argv[1] : "data/mech-holes-shark.off";
// Both of these must be positive in order to be considered
double max_hole_diam = (argc > 2) ? boost::lexical_cast<double>(argv[2]): -1.0;
int max_num_hole_edges = (argc > 3) ? boost::lexical_cast<int>(argv[3]) : -1;
std::ifstream input(filename);
Mesh mesh;
if ( !input || !(input >> mesh) ) {
std::cerr << "Not a valid off file." << std::endl;
return 1;
}
unsigned int nb_holes = 0;
std::vector<halfedge_descriptor> border_cycles;
// collect one halfedge per boundary cycle
CGAL::Polygon_mesh_processing::extract_boundary_cycles(mesh, std::back_inserter(border_cycles));
for(halfedge_descriptor h : border_cycles)
{
if(max_hole_diam > 0 && max_num_hole_edges > 0 &&
!is_small_hole(h, mesh, max_hole_diam, max_num_hole_edges))
continue;
std::vector<face_descriptor> patch_facets;
std::vector<vertex_descriptor> patch_vertices;
bool success = std::get<0>(
mesh,
h,
std::back_inserter(patch_facets),
std::back_inserter(patch_vertices)) );
std::cout << "* Number of facets in constructed patch: " << patch_facets.size() << std::endl;
std::cout << " Number of vertices in constructed patch: " << patch_vertices.size() << std::endl;
std::cout << " Is fairing successful: " << success << std::endl;
++nb_holes;
}
std::cout << std::endl;
std::cout << nb_holes << " holes have been filled" << std::endl;
std::string outfile = "filled_SM.off";
std::ofstream out(outfile.c_str());
std::cout << "Mesh written to: " << outfile << std::endl;
out.precision(17);
out << mesh << std::endl;
return 0;
}