\( \newcommand{\E}{\mathrm{E}} \) \( \newcommand{\A}{\mathrm{A}} \) \( \newcommand{\R}{\mathrm{R}} \) \( \newcommand{\N}{\mathrm{N}} \) \( \newcommand{\Q}{\mathrm{Q}} \) \( \newcommand{\Z}{\mathrm{Z}} \) \( \def\ccSum #1#2#3{ \sum_{#1}^{#2}{#3} } \def\ccProd #1#2#3{ \sum_{#1}^{#2}{#3} }\)
CGAL 4.14 - Polygon Mesh Processing
Polygon_mesh_processing/refine_fair_example.cpp
#include <CGAL/Exact_predicates_inexact_constructions_kernel.h>
#include <CGAL/Polyhedron_3.h>
#include <CGAL/Polygon_mesh_processing/refine.h>
#include <CGAL/Polygon_mesh_processing/fair.h>
#include <fstream>
#include <map>
typedef CGAL::Polyhedron_3<Kernel> Polyhedron;
typedef Polyhedron::Vertex_handle Vertex_handle;
// extract vertices which are at most k (inclusive)
// far from vertex v in the graph of edges
void extract_k_ring(Vertex_handle v,
int k,
std::vector<Vertex_handle>& qv)
{
std::map<Vertex_handle, int> D;
qv.push_back(v);
D[v] = 0;
std::size_t current_index = 0;
int dist_v;
while (current_index < qv.size() && (dist_v = D[qv[current_index]]) < k)
{
v = qv[current_index++];
Polyhedron::Halfedge_around_vertex_circulator e(v->vertex_begin()), e_end(e);
do {
Vertex_handle new_v = e->opposite()->vertex();
if (D.insert(std::make_pair(new_v, dist_v + 1)).second) {
qv.push_back(new_v);
}
} while (++e != e_end);
}
}
int main(int argc, char* argv[])
{
const char* filename = (argc > 1) ? argv[1] : "data/blobby.off";
std::ifstream input(filename);
Polyhedron poly;
if ( !input || !(input >> poly) || poly.empty()
std::cerr << "Not a valid input file." << std::endl;
return 1;
}
std::vector<Polyhedron::Facet_handle> new_facets;
std::vector<Vertex_handle> new_vertices;
faces(poly),
std::back_inserter(new_facets),
std::back_inserter(new_vertices),
CGAL::Polygon_mesh_processing::parameters::density_control_factor(2.));
std::ofstream refined_off("refined.off");
refined_off << poly;
refined_off.close();
std::cout << "Refinement added " << new_vertices.size() << " vertices." << std::endl;
Polyhedron::Vertex_iterator v = poly.vertices_begin();
std::advance(v, 82/*e.g.*/);
std::vector<Vertex_handle> region;
extract_k_ring(v, 12/*e.g.*/, region);
bool success = CGAL::Polygon_mesh_processing::fair(poly, region);
std::cout << "Fairing : " << (success ? "succeeded" : "failed") << std::endl;
std::ofstream faired_off("faired.off");
faired_off << poly;
faired_off.close();
return 0;
}