Ticket #7462: boost_geometry_union_bug.cpp

#include <iostream>
#include <boost/geometry.hpp>
#include <boost/geometry/geometries/adapted/c_array.hpp>
BOOST_GEOMETRY_REGISTER_C_ARRAY_CS(cs::cartesian)
#include <boost/geometry/geometries/polygon.hpp>
#include <boost/geometry/algorithms/union.hpp>

typedef float real_t;
typedef boost::geometry::model::d2::point_xy<real_t> pnt_t;
typedef boost::geometry::model::polygon<pnt_t> polygon_t;

void print(std::ostream& os, const std::string& name, const polygon_t& poly) {
        os << name << "={";
        bool first = true;
        for(auto& p : boost::geometry::exterior_ring(poly)) {
                if(!first) {
                        std::cout << ",";
                }
                else {
                        first = false;
                }
                os << "{" << p.x() << "," << p.y() << "}";
        }
        os << "};" << std::endl;
}

int main(int argc, char** argv)
{
        std::cout.precision(10);

        real_t data1[][2] = {{0,0}, {-0.3681253195,0.9297761917}, {2.421203136,2.034152031}, {2.789328575,1.104375958}, {0,0}};
        real_t data2[][2] = {{2.76143527,1.093332171}, {2.076887131,1.822299719}, {4.263789177,3.875944376}, {4.948337555,3.146976948}, {2.76143527,1.093332171}};

        polygon_t p1, p2;
        boost::geometry::append(p1, data1);
        boost::geometry::append(p2, data2);

        std::vector<polygon_t> output;
        boost::geometry::union_(p1, p2, output);

        print(std::cout, "p1", p1);
        print(std::cout, "p2", p2);
        print(std::cout, "i", output.front());

        return 1;
}