id	summary	reporter	owner	description	type	status	milestone	component	version	severity	resolution	keywords	cc
11789	Boost 1.59.0: geometry::intersection() asserts for spherical_equatorial coordinate system	Dave Stacey <drstacey@…>	Barend Gehrels	"For disjoint polygons, geometry::intersection() assert()s when used with the spherical_equatorial coordinate system. assert() comes from geometry::math::detail::normalize_spheroidal_coordinates<>::apply(), as shown by the following code:

{{{
#include <iostream>
#include <deque>

#include <boost/geometry.hpp>
#include <boost/geometry/geometries/point_xy.hpp>
#include <boost/geometry/geometries/polygon.hpp>
#include <boost/geometry/geometries/adapted/c_array.hpp>
#include <boost/foreach.hpp>

typedef boost::geometry::cs::spherical_equatorial<boost::geometry::degree> coordinate_system;
BOOST_GEOMETRY_REGISTER_C_ARRAY_CS(coordinate_system)

int main()
{
    typedef boost::geometry::model::point<double, 2, coordinate_system> point_t;
    typedef boost::geometry::model::polygon<point_t> polygon_t;

    double green_pts[][2] = {
        {-4.5726431789237223,52.142932977753595},
        {-4.5743166242433153,52.143359442355219},
        {-4.5739141406075410,52.143957260988416},
        {-4.5722406991324354,52.143530796430468},
        {-4.5726431789237223,52.142932977753595}};
    polygon_t green;
    boost::geometry::append(green, green_pts);

    double blue_pts[][2] = {
        {-4.5714644516017975,52.143819810922480},
        {-4.5670821923630358,52.143819810922480},
        {-4.5670821923630358,52.143649055226163},
        {-4.5714644516017975,52.143649055226163},
        {-4.5714644516017975,52.143819810922480}};
    polygon_t blue;
    boost::geometry::append(blue, green_pts);

    std::deque<polygon_t> output;
    // assert() comes from the following call...
    boost::geometry::intersection(green, blue, output);

    int i = 0;
    std::cout << ""green && blue:"" << std::endl;
    BOOST_FOREACH(polygon_t const& p, output)
    {
        std::cout << i++ << "": "" << boost::geometry::area(p) << std::endl;
    }

    return 0;
}
}}}

assert() is generated in the call to geometry::intersection(). Tested with both g++-4.9.3 and MSVC 2005 SP1. This is a regression on Boost 1.57.0, where the assert() is not produced.

assert() is only generated when using the cs::spherical_equatorial coordinate system; if cs::cartesian is used instead then the assert() is not generated.

Many thanks for your work on Boost and for looking at this ticket."	Bugs	closed	Boost 1.61.0	geometry	Boost 1.59.0	Problem	fixed