CGAL 5.2.1 - 2D Minkowski Sums
Minkowski_sum_2/approx_offset.cpp
// Computing the approximated offset of a polygon.
#include <fstream>
#include <CGAL/Timer.h>
#include <CGAL/approximated_offset_2.h>
#include "bops_circular.h"
typedef CGAL::Polygon_2<Kernel> Linear_polygon;
int main(int argc, char* argv[])
{
// Open the input file and read a polygon.
const char* filename = (argc > 1) ? argv[1] : "spiked.dat";
std::ifstream in_file(filename);
if (! in_file.is_open()) {
std::cerr << "Failed to open the input file." << std::endl;
return -1;
}
Linear_polygon P;
in_file >> P;
in_file.close();
std::cout << "Read an input polygon with " << P.size() << " vertices."
<< std::endl;
// Approximate the offset polygon with radius 5 and error bound 0.00001.
CGAL::Timer timer;
timer.start();
Polygon_with_holes_2 offset = CGAL::approximated_offset_2(P, 5, 0.00001);
double secs = timer.time();
std::cout << "The offset polygon has " << offset.outer_boundary().size()
<< " vertices, " << offset.number_of_holes() << " holes."
<< std::endl;
std::cout << "Offset computation took " << secs << " seconds." << std::endl;
return 0;
}