CGAL 5.6.1 - Polygon Mesh Processing
Polygon_mesh_processing/corefinement_difference_remeshed.cpp
#include <CGAL/Exact_predicates_inexact_constructions_kernel.h>
#include <CGAL/Surface_mesh.h>
#include <CGAL/Polygon_mesh_processing/corefinement.h>
#include <CGAL/Polygon_mesh_processing/IO/polygon_mesh_io.h>
#include <CGAL/Polygon_mesh_processing/remesh.h>
#include <CGAL/boost/graph/selection.h>
#include <fstream>
#include <iostream>
#include <iterator>
#include <vector>
typedef boost::graph_traits<Mesh>::halfedge_descriptor halfedge_descriptor;
typedef boost::graph_traits<Mesh>::edge_descriptor edge_descriptor;
typedef boost::graph_traits<Mesh>::face_descriptor face_descriptor;
namespace params = CGAL::parameters;
struct Vector_pmap_wrapper
{
std::vector<bool>& vect;
Vector_pmap_wrapper(std::vector<bool>& v) : vect(v) {}
friend bool get(const Vector_pmap_wrapper& m, face_descriptor f)
{
return m.vect[f];
}
friend void put(const Vector_pmap_wrapper& m, face_descriptor f, bool b)
{
m.vect[f]=b;
}
};
int main(int argc, char* argv[])
{
const std::string filename1 = (argc > 1) ? argv[1] : CGAL::data_file_path("meshes/blobby.off");
const std::string filename2 = (argc > 2) ? argv[2] : CGAL::data_file_path("meshes/eight.off");
Mesh mesh1, mesh2;
if(!PMP::IO::read_polygon_mesh(filename1, mesh1) || !PMP::IO::read_polygon_mesh(filename2, mesh2))
{
std::cerr << "Invalid input." << std::endl;
return 1;
}
//create a property on edges to indicate whether they are constrained
Mesh::Property_map<edge_descriptor,bool> is_constrained_map =
mesh1.add_property_map<edge_descriptor,bool>("e:is_constrained", false).first;
// update mesh1 to contain the mesh bounding the difference
// of the two input volumes.
bool valid_difference =
mesh2,
mesh1,
params::default_values(), // default parameters for mesh1
params::default_values(), // default parameters for mesh2
params::edge_is_constrained_map(is_constrained_map));
if (valid_difference)
{
std::cout << "Difference was successfully computed\n";
CGAL::IO::write_polygon_mesh("difference.off", mesh1, CGAL::parameters::stream_precision(17));
}
else
{
std::cout << "Difference could not be computed\n";
return 1;
}
// collect faces incident to a constrained edge
std::vector<face_descriptor> selected_faces;
std::vector<bool> is_selected(num_faces(mesh1), false);
for(edge_descriptor e : edges(mesh1))
if (is_constrained_map[e])
{
// insert all faces incident to the target vertex
for(halfedge_descriptor h : halfedges_around_target(halfedge(e,mesh1),mesh1))
{
if (!is_border(h, mesh1) )
{
face_descriptor f=face(h, mesh1);
if ( !is_selected[f] )
{
selected_faces.push_back(f);
is_selected[f]=true;
}
}
}
}
// increase the face selection
CGAL::expand_face_selection(selected_faces, mesh1, 2,
Vector_pmap_wrapper(is_selected), std::back_inserter(selected_faces));
std::cout << selected_faces.size()
<< " faces were selected for the remeshing step\n";
// remesh the region around the intersection polylines
PMP::isotropic_remeshing(selected_faces, 0.02, mesh1,
params::edge_is_constrained_map(is_constrained_map));
CGAL::IO::write_polygon_mesh("difference_remeshed.off", mesh1, CGAL::parameters::stream_precision(17));
return 0;
}