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#include <CGAL/Exact_predicates_inexact_constructions_kernel.h>
#include <CGAL/point_generators_3.h>
#include <CGAL/Real_timer.h>
#include <CGAL/compute_average_spacing.h>
#include <CGAL/grid_simplify_point_set.h>
#include <CGAL/jet_smooth_point_set.h>
#include <boost/lexical_cast.hpp>
#include <vector>
#include <fstream>
// Types
typedef CGAL::Exact_predicates_inexact_constructions_kernel Kernel;
typedef Kernel::FT FT;
typedef Kernel::Point_3 Point;
typedef CGAL::Random_points_on_sphere_3<Point> Generator;
// Concurrency
typedef CGAL::Parallel_if_available_tag Concurrency_tag;
// instance of std::function<bool(double)>
struct Progress_to_std_cerr_callback
{
mutable std::size_t nb;
CGAL::Real_timer timer;
double t_start;
mutable double t_latest;
const std::string name;
Progress_to_std_cerr_callback (const char* name)
: name (name)
{
timer.start();
t_start = timer.time();
t_latest = t_start;
}
bool operator()(double advancement) const
{
// Avoid calling time() at every single iteration, which could
// impact performances very badly
++ nb;
if (advancement != 1 && nb % 100 != 0)
return true;
double t = timer.time();
if (advancement == 1 || (t - t_latest) > 0.1) // Update every 1/10th of second
{
std::cerr << "\r" // Return at the beginning of same line and overwrite
<< name << ": " << int(advancement * 100) << "%";
if (advancement == 1)
std::cerr << std::endl;
t_latest = t;
}
return true;
}
};
int main (int argc, char* argv[])
{
int N = (argc > 1) ? boost::lexical_cast<int>(argv[1]) : 1000;
// Generate N points on a sphere of radius 100.
std::vector<Point> points;
points.reserve(N);
Generator generator(100.);
std::copy_n(generator, N, std::back_inserter(points));
// Compute average spacing
FT average_spacing = CGAL::compute_average_spacing<Concurrency_tag>
(points, 6,
CGAL::parameters::callback(Progress_to_std_cerr_callback("Computing average spacing")));
// Simplify on a grid with a size of twice the average spacing
points.erase(CGAL::grid_simplify_point_set(points, 2. * average_spacing,
CGAL::parameters::callback(Progress_to_std_cerr_callback("Grid simplification"))),
points.end());
// Smooth simplified point set
CGAL::jet_smooth_point_set<Concurrency_tag>(points, 6,
CGAL::parameters::callback(Progress_to_std_cerr_callback("Jet smoothing")));
return EXIT_SUCCESS;
}
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