CGAL 5.1.2 - Polygon Mesh Processing
Polygon_mesh_processing/compute_normals_example.cpp
#include <CGAL/Exact_predicates_inexact_constructions_kernel.h>
#include <CGAL/Surface_mesh.h>
#include <CGAL/Polygon_mesh_processing/compute_normal.h>
#include <iostream>
#include <fstream>
typedef K::Point_3 Point;
typedef K::Vector_3 Vector;
typedef CGAL::Surface_mesh<Point> Surface_mesh;
typedef boost::graph_traits<Surface_mesh>::vertex_descriptor vertex_descriptor;
typedef boost::graph_traits<Surface_mesh>::face_descriptor face_descriptor;
int main(int argc, char* argv[])
{
const char* filename = (argc > 1) ? argv[1] : "data/eight.off";
std::ifstream input(filename);
Surface_mesh mesh;
if (!input || !(input >> mesh) || mesh.is_empty()) {
std::cerr << "Not a valid off file." << std::endl;
return 1;
}
auto vnormals = mesh.add_property_map<vertex_descriptor, Vector>("v:normals", CGAL::NULL_VECTOR).first;
auto fnormals = mesh.add_property_map<face_descriptor, Vector>("f:normals", CGAL::NULL_VECTOR).first;
PMP::compute_normals(mesh, vnormals, fnormals);
std::cout << "Vertex normals :" << std::endl;
for(vertex_descriptor vd: vertices(mesh))
std::cout << vnormals[vd] << std::endl;
std::cout << "Face normals :" << std::endl;
for(face_descriptor fd: faces(mesh))
std::cout << fnormals[fd] << std::endl;
return 0;
}