From ccc40d3a0bcf5a6daad5784cb6d996c1faf41d80 Mon Sep 17 00:00:00 2001
From: Adam Wulkiewicz <adam.wulkiewicz@gmail.com>
Date: Wed, 9 Apr 2014 21:53:12 +0200
Subject: [PATCH] [relate] cleanup, increase the readability of relate()
 dispatching, remove unneeded code

---
 include/boost/geometry/algorithms/crosses.hpp |  51 +----
 .../algorithms/detail/relate/areal_areal.hpp  |  66 +++---
 .../algorithms/detail/relate/relate.hpp       | 207 +++++++-----------
 .../algorithms/detail/relate/turns.hpp        |  80 -------
 4 files changed, 112 insertions(+), 292 deletions(-)

diff --git a/include/boost/geometry/algorithms/crosses.hpp b/include/boost/geometry/algorithms/crosses.hpp
index 8effd3b59..caf380753 100644
--- a/include/boost/geometry/algorithms/crosses.hpp
+++ b/include/boost/geometry/algorithms/crosses.hpp
@@ -23,8 +23,6 @@
 
 #include <boost/geometry/core/access.hpp>
 
-#include <boost/geometry/algorithms/not_implemented.hpp>
-
 #include <boost/geometry/geometries/concepts/check.hpp>
 
 #include <boost/geometry/algorithms/detail/relate/relate.hpp>
@@ -32,46 +30,6 @@
 namespace boost { namespace geometry
 {
 
-#ifndef DOXYGEN_NO_DETAIL
-namespace detail { namespace crosses
-{
-
-struct use_relate
-{
-    template <typename Geometry1, typename Geometry2>
-    static inline bool apply(Geometry1 const& g1, Geometry2 const& g2)
-    {
-        typedef typename detail::relate::
-            static_mask_crosses_type<Geometry1, Geometry2>::type static_mask;
-
-        return detail::relate::relate<static_mask>(g1, g2);
-    }
-};
-
-}} // namespace detail::crosses
-#endif // DOXYGEN_NO_DETAIL
-
-#ifndef DOXYGEN_NO_DISPATCH
-namespace dispatch
-{
-
-
-template
-<
-    typename Geometry1,
-    typename Geometry2,
-    typename Tag1 = typename tag<Geometry1>::type,
-    typename Tag2 = typename tag<Geometry2>::type
->
-struct crosses
-    : detail::crosses::use_relate
-{};
-
-
-} // namespace dispatch
-#endif // DOXYGEN_NO_DISPATCH
-
-
 /*!
 \brief \brief_check2{crosses}
 \ingroup crosses
@@ -89,11 +47,10 @@ inline bool crosses(Geometry1 const& geometry1, Geometry2 const& geometry2)
     concept::check<Geometry1 const>();
     concept::check<Geometry2 const>();
 
-    return dispatch::crosses
-        <
-            Geometry1,
-            Geometry2
-        >::apply(geometry1, geometry2);
+    typedef typename detail::relate::
+        static_mask_crosses_type<Geometry1, Geometry2>::type static_mask;
+
+    return detail::relate::relate<static_mask>(geometry1, geometry2);
 }
 
 }} // namespace boost::geometry
diff --git a/include/boost/geometry/algorithms/detail/relate/areal_areal.hpp b/include/boost/geometry/algorithms/detail/relate/areal_areal.hpp
index e44c008a7..bc5b619a7 100644
--- a/include/boost/geometry/algorithms/detail/relate/areal_areal.hpp
+++ b/include/boost/geometry/algorithms/detail/relate/areal_areal.hpp
@@ -100,8 +100,9 @@ public:
 
             // Check if any interior ring is outside
             ring_identifier ring_id(0, -1, 0);
-            for ( ; ring_id.ring_index < boost::numeric_cast<int>(geometry::num_interior_rings(areal)) ;
-                    ++ring_id.ring_index )
+            int const irings_count = boost::numeric_cast<int>(
+                                        geometry::num_interior_rings(areal) );
+            for ( ; ring_id.ring_index < irings_count ; ++ring_id.ring_index )
             {
                 typename detail::sub_range_return_type<Areal const>::type
                     range_ref = detail::sub_range(areal, ring_id);
@@ -135,8 +136,9 @@ public:
 
             // Check if any interior ring is inside
             ring_identifier ring_id(0, -1, 0);
-            for ( ; ring_id.ring_index < boost::numeric_cast<int>(geometry::num_interior_rings(areal)) ;
-                    ++ring_id.ring_index )
+            int const irings_count = boost::numeric_cast<int>(
+                                        geometry::num_interior_rings(areal) );
+            for ( ; ring_id.ring_index < irings_count ; ++ring_id.ring_index )
             {
                 typename detail::sub_range_return_type<Areal const>::type
                     range_ref = detail::sub_range(areal, ring_id);
@@ -237,9 +239,7 @@ struct areal_areal
             {
                 // analyse sorted turns
                 turns_analyser<turn_type, 0> analyser;
-                analyse_each_turn(result, analyser,
-                                  turns.begin(), turns.end(),
-                                  geometry1, geometry2);
+                analyse_each_turn(result, analyser, turns.begin(), turns.end());
 
                 if ( result.interrupt )
                     return;
@@ -278,9 +278,7 @@ struct areal_areal
             {
                 // analyse sorted turns
                 turns_analyser<turn_type, 1> analyser;
-                analyse_each_turn(result, analyser,
-                                  turns.begin(), turns.end(),
-                                  geometry2, geometry1);
+                analyse_each_turn(result, analyser, turns.begin(), turns.end());
 
                 if ( result.interrupt )
                     return;
@@ -401,13 +399,8 @@ struct areal_areal
         {}
 
         template <typename Result,
-                  typename TurnIt,
-                  typename Geometry,
-                  typename OtherGeometry>
-        void apply(Result & result,
-                   TurnIt first, TurnIt it, TurnIt last,
-                   Geometry const& geometry,
-                   OtherGeometry const& other_geometry)
+                  typename TurnIt>
+        void apply(Result & result, TurnIt it)
         {
             //BOOST_ASSERT( it != last );
 
@@ -499,14 +492,8 @@ struct areal_areal
         }
 
         // it == last
-        template <typename Result,
-                  typename TurnIt,
-                  typename Geometry,
-                  typename OtherGeometry>
-        void apply(Result & result,
-                   TurnIt first, TurnIt last,
-                   Geometry const& geometry,
-                   OtherGeometry const& other_geometry)
+        template <typename Result>
+        void apply(Result & result)
         {
             //BOOST_ASSERT( first != last );
 
@@ -548,30 +535,24 @@ struct areal_areal
     // call analyser.apply() for each turn in range
     // IMPORTANT! The analyser is also called for the end iterator - last
     template <typename Result,
-              typename TurnIt,
               typename Analyser,
-              typename Geometry,
-              typename OtherGeometry>
+              typename TurnIt>
     static inline void analyse_each_turn(Result & res,
                                          Analyser & analyser,
-                                         TurnIt first, TurnIt last,
-                                         Geometry const& geometry,
-                                         OtherGeometry const& other_geometry)
+                                         TurnIt first, TurnIt last)
     {
         if ( first == last )
             return;
 
         for ( TurnIt it = first ; it != last ; ++it )
         {
-            analyser.apply(res, first, it, last,
-                           geometry, other_geometry);
+            analyser.apply(res, it);
 
             if ( res.interrupt )
                 return;
         }
 
-        analyser.apply(res, first, last,
-                       geometry, other_geometry);
+        analyser.apply(res);
     }
 
     template <std::size_t OpId, typename Result, typename Geometry, typename OtherGeometry>
@@ -810,16 +791,21 @@ struct areal_areal
         template <typename Analyser, typename Turn>
         static inline void for_preceding_rings(Analyser & analyser, Turn const& turn)
         {
-            for_no_turns_rings(analyser, turn, -1, turn.operations[OpId].seg_id.ring_index);
+            segment_identifier const& seg_id = turn.operations[OpId].seg_id;
+
+            for_no_turns_rings(analyser, turn, -1, seg_id.ring_index);
         }
 
         template <typename Analyser, typename Turn>
         static inline void for_following_rings(Analyser & analyser, Turn const& turn)
         {
-            std::size_t count = geometry::num_interior_rings(
-                                    detail::single_geometry(analyser.geometry,
-                                                            turn.operations[OpId].seg_id));
-            for_no_turns_rings(analyser, turn, turn.operations[OpId].seg_id.ring_index + 1, count);
+            segment_identifier const& seg_id = turn.operations[OpId].seg_id;
+
+            int count = boost::numeric_cast<int>(
+                            geometry::num_interior_rings(
+                                detail::single_geometry(analyser.geometry, seg_id)));
+            
+            for_no_turns_rings(analyser, turn, seg_id.ring_index + 1, count);
         }
 
         template <typename Analyser, typename Turn>
diff --git a/include/boost/geometry/algorithms/detail/relate/relate.hpp b/include/boost/geometry/algorithms/detail/relate/relate.hpp
index e4253daa1..2b8d96988 100644
--- a/include/boost/geometry/algorithms/detail/relate/relate.hpp
+++ b/include/boost/geometry/algorithms/detail/relate/relate.hpp
@@ -53,180 +53,137 @@ namespace boost { namespace geometry
 {
 
 #ifndef DOXYGEN_NO_DETAIL
-namespace detail_dispatch { namespace relate {
+namespace detail { namespace relate {
+
+// Those are used only to allow dispatch::relate to produce compile-time error
+
+template <typename Geometry,
+          typename Tag = typename geometry::tag<Geometry>::type>
+struct is_supported_by_generic
+{
+    static const bool value
+        = boost::is_same<Tag, linestring_tag>::value
+       || boost::is_same<Tag, multi_linestring_tag>::value
+       || boost::is_same<Tag, ring_tag>::value
+       || boost::is_same<Tag, polygon_tag>::value
+       || boost::is_same<Tag, multi_polygon_tag>::value;
+};
 
 template <typename Geometry1,
           typename Geometry2,
           typename Tag1 = typename geometry::tag<Geometry1>::type,
           typename Tag2 = typename geometry::tag<Geometry2>::type>
+struct is_generic
+{
+    static const bool value = is_supported_by_generic<Geometry1>::value
+                           && is_supported_by_generic<Geometry2>::value;
+};
+
+
+template <typename Point, typename Geometry, typename Tag>
+struct is_generic<Point, Geometry, point_tag, Tag>
+{
+    static const bool value = is_supported_by_generic<Geometry>::value;
+};
+
+template <typename Geometry, typename Point, typename Tag>
+struct is_generic<Geometry, Point, Tag, point_tag>
+{
+    static const bool value = is_supported_by_generic<Geometry>::value;
+};
+
+template <typename Point1, typename Point2>
+struct is_generic<Point1, Point2, point_tag, point_tag>
+{
+    static const bool value = false;
+};
+
+
+}} // namespace detail::relate
+
+#ifndef DOXYGEN_NO_DISPATCH
+namespace detail_dispatch { namespace relate {
+
+
+template <typename Geometry1,
+          typename Geometry2,
+          typename Tag1 = typename geometry::tag<Geometry1>::type,
+          typename Tag2 = typename geometry::tag<Geometry2>::type,
+          int TopDim1 = geometry::topological_dimension<Geometry1>::value,
+          int TopDim2 = geometry::topological_dimension<Geometry2>::value,
+          bool IsGeneric = detail::relate::is_generic<Geometry1, Geometry2>::value
+>
 struct relate : not_implemented<Tag1, Tag2>
 {};
 
+
 template <typename Point1, typename Point2>
-struct relate<Point1, Point2, point_tag, point_tag>
+struct relate<Point1, Point2, point_tag, point_tag, 0, 0, false>
     : detail::relate::point_point<Point1, Point2>
 {};
 
 template <typename Point, typename MultiPoint>
-struct relate<Point, MultiPoint, point_tag, multi_point_tag>
+struct relate<Point, MultiPoint, point_tag, multi_point_tag, 0, 0, false>
     : detail::relate::point_multipoint<Point, MultiPoint>
 {};
 
 template <typename MultiPoint, typename Point>
-struct relate<MultiPoint, Point, multi_point_tag, point_tag>
+struct relate<MultiPoint, Point, multi_point_tag, point_tag, 0, 0, false>
     : detail::relate::multipoint_point<MultiPoint, Point>
 {};
 
 template <typename MultiPoint1, typename MultiPoint2>
-struct relate<MultiPoint1, MultiPoint2, multi_point_tag, multi_point_tag>
+struct relate<MultiPoint1, MultiPoint2, multi_point_tag, multi_point_tag, 0, 0, false>
     : detail::relate::multipoint_multipoint<MultiPoint1, MultiPoint2>
 {};
 
-//template <typename Point, typename Box>
-//struct relate<Point, Box, point_tag, box_tag>
+//template <typename Point, typename Box, int TopDim2>
+//struct relate<Point, Box, point_tag, box_tag, 0, TopDim2, false>
 //    : detail::relate::point_box<Point, Box>
 //{};
 //
-//template <typename Box, typename Point>
-//struct relate<Box, Point, box_tag, point_tag>
+//template <typename Box, typename Point, int TopDim1>
+//struct relate<Box, Point, box_tag, point_tag, TopDim1, 0, false>
 //    : detail::relate::box_point<Box, Point>
 //{};
 
-template <typename Point, typename Geometry, typename Tag2>
-struct relate<Point, Geometry, point_tag, Tag2>
+
+template <typename Point, typename Geometry, typename Tag2, int TopDim2>
+struct relate<Point, Geometry, point_tag, Tag2, 0, TopDim2, true>
     : detail::relate::point_geometry<Point, Geometry>
 {};
 
-template <typename Geometry, typename Point, typename Tag1>
-struct relate<Geometry, Point, Tag1, point_tag>
+template <typename Geometry, typename Point, typename Tag1, int TopDim1>
+struct relate<Geometry, Point, Tag1, point_tag, TopDim1, 0, true>
     : detail::relate::geometry_point<Geometry, Point>
 {};
 
 
-template <typename Linestring1, typename Linestring2>
-struct relate<Linestring1, Linestring2, linestring_tag, linestring_tag>
-    : detail::relate::linear_linear<Linestring1, Linestring2>
-{};
-
-template <typename Linestring, typename MultiLinestring>
-struct relate<Linestring, MultiLinestring, linestring_tag, multi_linestring_tag>
-    : detail::relate::linear_linear<Linestring, MultiLinestring>
-{};
-
-template <typename MultiLinestring, typename Linestring>
-struct relate<MultiLinestring, Linestring, multi_linestring_tag, linestring_tag>
-    : detail::relate::linear_linear<MultiLinestring, Linestring>
-{};
-
-template <typename MultiLinestring1, typename MultiLinestring2>
-struct relate<MultiLinestring1, MultiLinestring2, multi_linestring_tag, multi_linestring_tag>
-    : detail::relate::linear_linear<MultiLinestring1, MultiLinestring2>
+template <typename Linear1, typename Linear2, typename Tag1, typename Tag2>
+struct relate<Linear1, Linear2, Tag1, Tag2, 1, 1, true>
+    : detail::relate::linear_linear<Linear1, Linear2>
 {};
 
 
-template <typename Linestring, typename Polygon>
-struct relate<Linestring, Polygon, linestring_tag, polygon_tag>
-    : detail::relate::linear_areal<Linestring, Polygon>
-{};
-template <typename Linestring, typename Ring>
-struct relate<Linestring, Ring, linestring_tag, ring_tag>
-    : detail::relate::linear_areal<Linestring, Ring>
+template <typename Linear, typename Areal, typename Tag1, typename Tag2>
+struct relate<Linear, Areal, Tag1, Tag2, 1, 2, true>
+    : detail::relate::linear_areal<Linear, Areal>
 {};
 
-template <typename Polygon, typename Linestring>
-struct relate<Polygon, Linestring, polygon_tag, linestring_tag>
-    : detail::relate::areal_linear<Polygon, Linestring>
-{};
-template <typename Ring, typename Linestring>
-struct relate<Ring, Linestring, ring_tag, linestring_tag>
-    : detail::relate::areal_linear<Ring, Linestring>
-{};
-
-template <typename Linestring, typename MultiPolygon>
-struct relate<Linestring, MultiPolygon, linestring_tag, multi_polygon_tag>
-    : detail::relate::linear_areal<Linestring, MultiPolygon>
-{};
-
-template <typename MultiPolygon, typename Linestring>
-struct relate<MultiPolygon, Linestring, multi_polygon_tag, linestring_tag>
-    : detail::relate::areal_linear<MultiPolygon, Linestring>
-{};
-
-template <typename MultiLinestring, typename Polygon>
-struct relate<MultiLinestring, Polygon, multi_linestring_tag, polygon_tag>
-    : detail::relate::linear_areal<MultiLinestring, Polygon>
-{};
-template <typename MultiLinestring, typename Ring>
-struct relate<MultiLinestring, Ring, multi_linestring_tag, ring_tag>
-    : detail::relate::linear_areal<MultiLinestring, Ring>
-{};
-
-template <typename Polygon, typename MultiLinestring>
-struct relate<Polygon, MultiLinestring, polygon_tag, multi_linestring_tag>
-    : detail::relate::areal_linear<Polygon, MultiLinestring>
-{};
-template <typename Ring, typename MultiLinestring>
-struct relate<Ring, MultiLinestring, ring_tag, multi_linestring_tag>
-    : detail::relate::areal_linear<Ring, MultiLinestring>
-{};
-
-template <typename MultiLinestring, typename MultiPolygon>
-struct relate<MultiLinestring, MultiPolygon, multi_linestring_tag, multi_polygon_tag>
-    : detail::relate::linear_areal<MultiLinestring, MultiPolygon>
-{};
-
-template <typename MultiPolygon, typename MultiLinestring>
-struct relate<MultiPolygon, MultiLinestring, multi_polygon_tag, multi_linestring_tag>
-    : detail::relate::areal_linear<MultiPolygon, MultiLinestring>
+template <typename Areal, typename Linear, typename Tag1, typename Tag2>
+struct relate<Areal, Linear, Tag1, Tag2, 2, 1, true>
+    : detail::relate::areal_linear<Areal, Linear>
 {};
 
 
-template <typename Polygon1, typename Polygon2>
-struct relate<Polygon1, Polygon2, polygon_tag, polygon_tag>
-    : detail::relate::areal_areal<Polygon1, Polygon2>
+template <typename Areal1, typename Areal2, typename Tag1, typename Tag2>
+struct relate<Areal1, Areal2, Tag1, Tag2, 2, 2, true>
+    : detail::relate::areal_areal<Areal1, Areal2>
 {};
 
-template <typename Ring, typename Polygon>
-struct relate<Ring, Polygon, ring_tag, polygon_tag>
-    : detail::relate::areal_areal<Ring, Polygon>
-{};
-
-template <typename Polygon, typename Ring>
-struct relate<Polygon, Ring, polygon_tag, ring_tag>
-    : detail::relate::areal_areal<Polygon, Ring>
-{};
-
-template <typename Ring1, typename Ring2>
-struct relate<Ring1, Ring2, ring_tag, ring_tag>
-    : detail::relate::areal_areal<Ring1, Ring2>
-{};
-
-template <typename Polygon, typename MultiPolygon>
-struct relate<Polygon, MultiPolygon, polygon_tag, multi_polygon_tag>
-    : detail::relate::areal_areal<Polygon, MultiPolygon>
-{};
-
-template <typename MultiPolygon, typename Polygon>
-struct relate<MultiPolygon, Polygon, multi_polygon_tag, polygon_tag>
-    : detail::relate::areal_areal<MultiPolygon, Polygon>
-{};
-
-template <typename Ring, typename MultiPolygon>
-struct relate<Ring, MultiPolygon, ring_tag, multi_polygon_tag>
-    : detail::relate::areal_areal<Ring, MultiPolygon>
-{};
-
-template <typename MultiPolygon, typename Ring>
-struct relate<MultiPolygon, Ring, multi_polygon_tag, ring_tag>
-    : detail::relate::areal_areal<MultiPolygon, Ring>
-{};
-
-template <typename MultiPolygon1, typename MultiPolygon2>
-struct relate<MultiPolygon1, MultiPolygon2, multi_polygon_tag, multi_polygon_tag>
-    : detail::relate::areal_areal<MultiPolygon1, MultiPolygon2>
-{};
 
 }} // namespace detail_dispatch::relate
+#endif // DOXYGEN_NO_DISPATCH
 
 namespace detail { namespace relate {
 
diff --git a/include/boost/geometry/algorithms/detail/relate/turns.hpp b/include/boost/geometry/algorithms/detail/relate/turns.hpp
index 6664d4529..68eade8f0 100644
--- a/include/boost/geometry/algorithms/detail/relate/turns.hpp
+++ b/include/boost/geometry/algorithms/detail/relate/turns.hpp
@@ -227,86 +227,6 @@ struct less
     }
 };
 
-//template <typename Turn> inline
-//bool is_valid_method(Turn const& turn)
-//{
-//    return turn.method != detail::overlay::method_none
-//        && turn.method != detail::overlay::method_disjoint
-//        && turn.method != detail::overlay::method_error;
-//}
-//
-//template <typename Turn> inline
-//bool is_valid_operation(Turn const& turn)
-//{
-//    BOOST_ASSERT(!turn.has(detail::overlay::operation_opposite));
-//    return !turn.both(detail::overlay::operation_none);
-//}
-//
-//template <typename Turn> inline
-//bool is_valid_turn(Turn const& turn)
-//{
-//    return is_valid_method(turn) && is_valid_operation(turn);
-//}
-//
-//template <bool IsCyclic, typename TurnIt, typename Cond> inline
-//TurnIt find_next_if(TurnIt first, TurnIt current, TurnIt last, Cond cond)
-//{
-//    if ( first == last )
-//        return last;
-//
-//    if ( current != last )
-//    {
-//        TurnIt it = current;
-//        ++it;
-//
-//        for ( ; it != last ; ++it )
-//            if ( cond(*it) )
-//                return it;
-//    }
-//
-//    if ( IsCyclic )
-//    {
-//        for ( TurnIt it = first ; it != current ; ++it )
-//            if ( cond(*it) )
-//                return it;
-//    }
-//
-//    return last;
-//}
-//
-//template <bool IsCyclic, typename TurnIt, typename Cond> inline
-//TurnIt find_previous_if(TurnIt first, TurnIt current, TurnIt last, Cond cond)
-//{
-//    typedef std::reverse_iterator<TurnIt> Rit;
-//    Rit rlast = Rit(first);
-//    if ( current == last )
-//        return last;
-//    ++current;
-//    Rit res = find_next_if<IsCyclic>(Rit(last), Rit(current), rlast, cond);
-//    if ( res == rlast )
-//        return last;
-//    else
-//        return --res.base();
-//}
-//
-//template <typename TurnIt, typename Cond> inline
-//TurnIt find_first_if(TurnIt first, TurnIt last, Cond cond)
-//{
-//    return std::find_if(first, last, cond);
-//}
-//
-//template <typename TurnIt, typename Cond> inline
-//TurnIt find_last_if(TurnIt first, TurnIt last, Cond cond)
-//{
-//    typedef std::reverse_iterator<TurnIt> Rit;
-//    Rit rlast = Rit(first);
-//    Rit res = std::find_if(Rit(last), rlast, cond);
-//    if ( res == rlast )
-//        return last;
-//    else
-//        return --res.base();
-//}
-
 }}} // namespace detail::relate::turns
 #endif // DOXYGEN_NO_DETAIL