| // Boost.Geometry (aka GGL, Generic Geometry Library) |
| |
| // Copyright (c) 2007-2012 Barend Gehrels, Amsterdam, the Netherlands. |
| |
| // Use, modification and distribution is subject to the Boost Software License, |
| // Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at |
| // http://www.boost.org/LICENSE_1_0.txt) |
| |
| #ifndef BOOST_GEOMETRY_ALGORITHMS_DETAIL_OVERLAY_ASSIGN_PARENTS_HPP |
| #define BOOST_GEOMETRY_ALGORITHMS_DETAIL_OVERLAY_ASSIGN_PARENTS_HPP |
| |
| #include <boost/geometry/algorithms/area.hpp> |
| #include <boost/geometry/algorithms/envelope.hpp> |
| #include <boost/geometry/algorithms/expand.hpp> |
| #include <boost/geometry/algorithms/detail/partition.hpp> |
| #include <boost/geometry/algorithms/detail/overlay/get_ring.hpp> |
| #include <boost/geometry/algorithms/within.hpp> |
| |
| #include <boost/geometry/geometries/box.hpp> |
| |
| namespace boost { namespace geometry |
| { |
| |
| |
| #ifndef DOXYGEN_NO_DETAIL |
| namespace detail { namespace overlay |
| { |
| |
| |
| |
| template |
| < |
| typename Item, |
| typename Geometry1, typename Geometry2, |
| typename RingCollection |
| > |
| static inline bool within_selected_input(Item const& item2, ring_identifier const& ring_id, |
| Geometry1 const& geometry1, Geometry2 const& geometry2, |
| RingCollection const& collection) |
| { |
| typedef typename geometry::tag<Geometry1>::type tag1; |
| typedef typename geometry::tag<Geometry2>::type tag2; |
| |
| switch (ring_id.source_index) |
| { |
| case 0 : |
| return geometry::within(item2.point, |
| get_ring<tag1>::apply(ring_id, geometry1)); |
| break; |
| case 1 : |
| return geometry::within(item2.point, |
| get_ring<tag2>::apply(ring_id, geometry2)); |
| break; |
| case 2 : |
| return geometry::within(item2.point, |
| get_ring<void>::apply(ring_id, collection)); |
| break; |
| } |
| return false; |
| } |
| |
| |
| template <typename Point> |
| struct ring_info_helper |
| { |
| typedef typename geometry::default_area_result<Point>::type area_type; |
| |
| ring_identifier id; |
| area_type real_area; |
| area_type abs_area; |
| model::box<Point> envelope; |
| |
| inline ring_info_helper() |
| : real_area(0), abs_area(0) |
| {} |
| |
| inline ring_info_helper(ring_identifier i, area_type a) |
| : id(i), real_area(a), abs_area(geometry::math::abs(a)) |
| {} |
| }; |
| |
| |
| struct ring_info_helper_get_box |
| { |
| template <typename Box, typename InputItem> |
| static inline void apply(Box& total, InputItem const& item) |
| { |
| geometry::expand(total, item.envelope); |
| } |
| }; |
| |
| struct ring_info_helper_ovelaps_box |
| { |
| template <typename Box, typename InputItem> |
| static inline bool apply(Box const& box, InputItem const& item) |
| { |
| return ! geometry::detail::disjoint::disjoint_box_box(box, item.envelope); |
| } |
| }; |
| |
| template <typename Geometry1, typename Geometry2, typename Collection, typename RingMap> |
| struct assign_visitor |
| { |
| typedef typename RingMap::mapped_type ring_info_type; |
| |
| Geometry1 const& m_geometry1; |
| Geometry2 const& m_geometry2; |
| Collection const& m_collection; |
| RingMap& m_ring_map; |
| bool m_check_for_orientation; |
| |
| |
| inline assign_visitor(Geometry1 const& g1, Geometry2 const& g2, Collection const& c, |
| RingMap& map, bool check) |
| : m_geometry1(g1) |
| , m_geometry2(g2) |
| , m_collection(c) |
| , m_ring_map(map) |
| , m_check_for_orientation(check) |
| {} |
| |
| template <typename Item> |
| inline void apply(Item const& outer, Item const& inner, bool first = true) |
| { |
| if (first && outer.abs_area < inner.abs_area) |
| { |
| // Apply with reversed arguments |
| apply(inner, outer, false); |
| return; |
| } |
| |
| if (m_check_for_orientation |
| || (math::larger(outer.real_area, 0) |
| && math::smaller(inner.real_area, 0))) |
| { |
| ring_info_type& inner_in_map = m_ring_map[inner.id]; |
| |
| if (geometry::within(inner_in_map.point, outer.envelope) |
| && within_selected_input(inner_in_map, outer.id, m_geometry1, m_geometry2, m_collection) |
| ) |
| { |
| // Assign a parent if there was no earlier parent, or the newly |
| // found parent is smaller than the previous one |
| if (inner_in_map.parent.source_index == -1 |
| || outer.abs_area < inner_in_map.parent_area) |
| { |
| inner_in_map.parent = outer.id; |
| inner_in_map.parent_area = outer.abs_area; |
| } |
| } |
| } |
| } |
| }; |
| |
| |
| |
| |
| template |
| < |
| typename Geometry1, typename Geometry2, |
| typename RingCollection, |
| typename RingMap |
| > |
| inline void assign_parents(Geometry1 const& geometry1, |
| Geometry2 const& geometry2, |
| RingCollection const& collection, |
| RingMap& ring_map, |
| bool check_for_orientation = false) |
| { |
| typedef typename geometry::tag<Geometry1>::type tag1; |
| typedef typename geometry::tag<Geometry2>::type tag2; |
| |
| typedef typename RingMap::mapped_type ring_info_type; |
| typedef typename ring_info_type::point_type point_type; |
| typedef model::box<point_type> box_type; |
| |
| typedef typename RingMap::iterator map_iterator_type; |
| |
| { |
| typedef ring_info_helper<point_type> helper; |
| typedef std::vector<helper> vector_type; |
| typedef typename boost::range_iterator<vector_type const>::type vector_iterator_type; |
| |
| std::size_t count_total = ring_map.size(); |
| std::size_t count_positive = 0; |
| std::size_t index_positive = 0; // only used if count_positive>0 |
| std::size_t index = 0; |
| |
| // Copy to vector (with new approach this might be obsolete as well, using the map directly) |
| vector_type vector(count_total); |
| |
| for (map_iterator_type it = boost::begin(ring_map); |
| it != boost::end(ring_map); ++it, ++index) |
| { |
| vector[index] = helper(it->first, it->second.get_area()); |
| helper& item = vector[index]; |
| switch(it->first.source_index) |
| { |
| case 0 : |
| geometry::envelope(get_ring<tag1>::apply(it->first, geometry1), |
| item.envelope); |
| break; |
| case 1 : |
| geometry::envelope(get_ring<tag2>::apply(it->first, geometry2), |
| item.envelope); |
| break; |
| case 2 : |
| geometry::envelope(get_ring<void>::apply(it->first, collection), |
| item.envelope); |
| break; |
| } |
| if (item.real_area > 0) |
| { |
| count_positive++; |
| index_positive = index; |
| } |
| } |
| |
| if (! check_for_orientation) |
| { |
| if (count_positive == count_total) |
| { |
| // Optimization for only positive rings |
| // -> no assignment of parents or reversal necessary, ready here. |
| return; |
| } |
| |
| if (count_positive == 1) |
| { |
| // Optimization for one outer ring |
| // -> assign this as parent to all others (all interior rings) |
| // In unions, this is probably the most occuring case and gives |
| // a dramatic improvement (factor 5 for star_comb testcase) |
| ring_identifier id_of_positive = vector[index_positive].id; |
| ring_info_type& outer = ring_map[id_of_positive]; |
| index = 0; |
| for (vector_iterator_type it = boost::begin(vector); |
| it != boost::end(vector); ++it, ++index) |
| { |
| if (index != index_positive) |
| { |
| ring_info_type& inner = ring_map[it->id]; |
| inner.parent = id_of_positive; |
| outer.children.push_back(it->id); |
| } |
| } |
| return; |
| } |
| } |
| |
| assign_visitor |
| < |
| Geometry1, Geometry2, |
| RingCollection, RingMap |
| > visitor(geometry1, geometry2, collection, ring_map, check_for_orientation); |
| |
| geometry::partition |
| < |
| box_type, ring_info_helper_get_box, ring_info_helper_ovelaps_box |
| >::apply(vector, visitor); |
| } |
| |
| if (check_for_orientation) |
| { |
| for (map_iterator_type it = boost::begin(ring_map); |
| it != boost::end(ring_map); ++it) |
| { |
| if (geometry::math::equals(it->second.get_area(), 0)) |
| { |
| it->second.discarded = true; |
| } |
| else if (it->second.parent.source_index >= 0 |
| && math::larger(it->second.get_area(), 0)) |
| { |
| const ring_info_type& parent = ring_map[it->second.parent]; |
| |
| if (math::larger(parent.area, 0)) |
| { |
| // Discard positive inner ring with positive parent |
| it->second.discarded = true; |
| } |
| // Remove parent ID from any positive inner ring |
| it->second.parent.source_index = -1; |
| } |
| else if (it->second.parent.source_index < 0 |
| && math::smaller(it->second.get_area(), 0)) |
| { |
| // Reverse negative ring without parent |
| it->second.reversed = true; |
| } |
| } |
| } |
| |
| // Assign childlist |
| for (map_iterator_type it = boost::begin(ring_map); |
| it != boost::end(ring_map); ++it) |
| { |
| if (it->second.parent.source_index >= 0) |
| { |
| ring_map[it->second.parent].children.push_back(it->first); |
| } |
| } |
| } |
| |
| |
| // Version for one geometry (called by buffer) |
| template |
| < |
| typename Geometry, |
| typename RingCollection, |
| typename RingMap |
| > |
| inline void assign_parents(Geometry const& geometry, |
| RingCollection const& collection, |
| RingMap& ring_map, |
| bool check_for_orientation) |
| { |
| // Call it with an empty geometry as second geometry (source_id == 1) |
| // (ring_map should be empty for source_id==1) |
| |
| Geometry empty; |
| assign_parents(geometry, empty, collection, ring_map, check_for_orientation); |
| } |
| |
| |
| }} // namespace detail::overlay |
| #endif // DOXYGEN_NO_DETAIL |
| |
| |
| }} // namespace geometry |
| |
| |
| #endif // BOOST_GEOMETRY_ALGORITHMS_DETAIL_OVERLAY_ASSIGN_PARENTS_HPP |