\( \newcommand{\E}{\mathrm{E}} \) \( \newcommand{\A}{\mathrm{A}} \) \( \newcommand{\R}{\mathrm{R}} \) \( \newcommand{\N}{\mathrm{N}} \) \( \newcommand{\Q}{\mathrm{Q}} \) \( \newcommand{\Z}{\mathrm{Z}} \) \( \def\ccSum #1#2#3{ \sum_{#1}^{#2}{#3} } \def\ccProd #1#2#3{ \sum_{#1}^{#2}{#3} }\)
CGAL 5.0.3 - 2D Convex Hulls and Extreme Points
Convex_hull_2/convex_hull_indices_2.cpp
#include <CGAL/Exact_predicates_inexact_constructions_kernel.h>
#include <CGAL/convex_hull_2.h>
#include <CGAL/Convex_hull_traits_adapter_2.h>
#include <CGAL/property_map.h>
#include <vector>
#include <numeric>
typedef K::Point_2 Point_2;
CGAL::Pointer_property_map<Point_2>::type > Convex_hull_traits_2;
int main()
{
std::vector<Point_2> points = { Point_2(10,0),
Point_2(10,0),
Point_2(0,10),
Point_2(1,1),
Point_2(3,4),
Point_2(0,0),
Point_2(10,10),
Point_2(2,6) };
std::vector<std::size_t> indices(points.size()), out;
std::iota(indices.begin(), indices.end(),0);
CGAL::convex_hull_2(indices.begin(), indices.end(), std::back_inserter(out),
Convex_hull_traits_2(CGAL::make_property_map(points)));
for( std::size_t i : out){
std::cout << "points[" << i << "] = " << points[i] << std::endl;
}
return 0;
}