CGAL 5.1.2 - 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/remesh.h>
#include <CGAL/boost/graph/selection.h>
#include <fstream>
typedef boost::graph_traits<Mesh>::edge_descriptor edge_descriptor;
typedef boost::graph_traits<Mesh>::face_descriptor face_descriptor;
typedef boost::graph_traits<Mesh>::halfedge_descriptor halfedge_descriptor;
namespace params = PMP::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 char* filename1 = (argc > 1) ? argv[1] : "data/blobby.off";
const char* filename2 = (argc > 2) ? argv[2] : "data/eight.off";
std::ifstream input(filename1);
Mesh mesh1, mesh2;
if (!input || !(input >> mesh1))
{
std::cerr << "First mesh is not a valid off file." << std::endl;
return 1;
}
input.close();
input.open(filename2);
if (!input || !(input >> mesh2))
{
std::cerr << "Second mesh is not a valid off file." << 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::all_default(), // default parameters for mesh1
params::all_default(), // default parameters for mesh2
params::edge_is_constrained_map(is_constrained_map));
if (valid_difference)
{
std::cout << "Difference was successfully computed\n";
std::ofstream output("difference.off");
output.precision(17);
output << mesh1;
}
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
selected_faces,
0.02,
mesh1,
params::edge_is_constrained_map(is_constrained_map) );
std::ofstream output("difference_remeshed.off");
output.precision(17);
output << mesh1;
return 0;
}