diff options
Diffstat (limited to 'boost/geometry/algorithms/detail/overlay/get_ring.hpp')
| -rw-r--r-- | boost/geometry/algorithms/detail/overlay/get_ring.hpp | 15 |
1 files changed, 13 insertions, 2 deletions
diff --git a/boost/geometry/algorithms/detail/overlay/get_ring.hpp b/boost/geometry/algorithms/detail/overlay/get_ring.hpp index 460c30def3..07e984b194 100644 --- a/boost/geometry/algorithms/detail/overlay/get_ring.hpp +++ b/boost/geometry/algorithms/detail/overlay/get_ring.hpp @@ -18,6 +18,8 @@ #include <boost/geometry/core/ring_type.hpp> #include <boost/geometry/core/tags.hpp> #include <boost/geometry/algorithms/detail/ring_identifier.hpp> +#include <boost/geometry/algorithms/detail/overlay/segment_identifier.hpp> +#include <boost/geometry/algorithms/num_points.hpp> #include <boost/geometry/geometries/concepts/check.hpp> #include <boost/geometry/util/range.hpp> @@ -49,8 +51,6 @@ struct get_ring<void> }; - - template<> struct get_ring<ring_tag> { @@ -113,6 +113,17 @@ struct get_ring<multi_polygon_tag> }; +template <typename Geometry> +inline std::size_t segment_count_on_ring(Geometry const& geometry, + segment_identifier const& seg_id) +{ + typedef typename geometry::tag<Geometry>::type tag; + ring_identifier const rid(0, seg_id.multi_index, seg_id.ring_index); + // A closed polygon, a triangle of 4 points, including starting point, + // contains 3 segments. So handle as if closed and subtract one. + return geometry::num_points(detail::overlay::get_ring<tag>::apply(rid, geometry), true) - 1; +} + }} // namespace detail::overlay #endif // DOXYGEN_NO_DETAIL |