Ticket #10398: main_boost_geometry_polygon_offset_problem.cpp

#include <iostream>

#include <boost/geometry/geometry.hpp>

#include <boost/geometry/geometries/point_xy.hpp>
#include <boost/geometry/geometries/polygon.hpp>
#include <boost/geometry/geometries/multi_polygon.hpp>

#include <boost/geometry/algorithms/buffer.hpp>

#include <boost/geometry/strategies/cartesian/buffer_join_miter.hpp>
#include <boost/geometry/strategies/cartesian/buffer_end_flat.hpp>
#include <boost/geometry/strategies/cartesian/buffer_point_square.hpp>
#include <boost/geometry/strategies/cartesian/buffer_side_straight.hpp>

#include <boost/geometry/io/wkt/read.hpp>
#include <boost/geometry/io/wkt/write.hpp>

using namespace std;

int main(int argc, char** argv)
{
    typedef double coordinate_type;
    typedef boost::geometry::model::d2::point_xy<coordinate_type> point_xy_type;
    typedef boost::geometry::model::polygon<point_xy_type> polygon_type;
    boost::geometry::strategy::buffer::end_flat end_strategy;
    boost::geometry::strategy::buffer::point_square point_strategy;
    boost::geometry::strategy::buffer::side_straight side_strategy;

    vector<string> polygon_geometries;
    polygon_geometries.push_back("POLYGON((897866.5 6272518.7,897882.5 6272519.2,897882.6 6272519,897883.3 6272508.7,897883.5 6272505.5,897855 6272503.5,897852.4 6272505.6,897850.1 6272517.6,897860.8 6272518.5,897866.5 6272518.7))");
    polygon_geometries.push_back("POLYGON((898882.3 6271337.3,898895.7 6271339.9,898898 6271328.3,898881.6 6271325.1,898879.3 6271336.7,898882.3 6271337.3))");
    polygon_geometries.push_back("POLYGON((897558.7 6272055,897552.5 6272054.2,897552.5 6272053.7,897546.1 6272052.7,897545.6 6272057.7,897560.7 6272059.6,897560.9 6272055.3,897558.7 6272055))");
    polygon_geometries.push_back("POLYGON((898563.3 6272366.9,898554.7 6272379.2,898559.7 6272382.3,898561.6 6272379.4,898568.7 6272369.1,898563.8 6272366.2,898563.3 6272366.9))");

    for(unsigned int i=0;i<polygon_geometries.size();++i)
    {
        for(unsigned int j=0;j<100;++j)
        {
            double offset_distance = j/10.;

            boost::geometry::strategy::buffer::distance_symmetric<coordinate_type> distance_strategy(offset_distance);
            boost::geometry::strategy::buffer::join_miter join_strategy(offset_distance);

            polygon_type input;
            boost::geometry::model::multi_polygon<polygon_type> output;

            boost::geometry::read_wkt(polygon_geometries[i], input);
            // Just to give it a try, but does not change anything
            //boost::geometry::correct(input);

            /*
            for(unsigned int k=0;k<input.outer().size();++k)
                input.outer()[k] = point_xy_type(input.outer()[k].x() - input.outer()[0].x() , input.outer()[k].y() - input.outer()[0].y());
            */

            boost::geometry::buffer(input, output, distance_strategy, side_strategy, join_strategy, end_strategy, point_strategy);

            if(output.size() == 0)
                cout << "Unable to offset (" << offset_distance << ") input polygon with index " << i << endl;
        }
    }

        return 0;
}