[Boost-commit] svn:boost r76003 - in trunk: boost/geometry/algorithms libs/geometry/doc/src/docutils/tools/support_status

Subject: [Boost-commit] svn:boost r76003 - in trunk: boost/geometry/algorithms libs/geometry/doc/src/docutils/tools/support_status
From: bruno.lalande_at_[hidden]
Date: 2011-12-16 18:16:23

Author: bruno.lalande
Date: 2011-12-16 18:16:22 EST (Fri, 16 Dec 2011)
New Revision: 76003
URL: http://svn.boost.org/trac/boost/changeset/76003

Log:
Had dispatch::distance take care of the default strategy retrieval/inversion.
Text files modified: 
   trunk/boost/geometry/algorithms/distance.hpp                                 |    86 +++++++++++++++++++++++++++------------ 
   trunk/libs/geometry/doc/src/docutils/tools/support_status/support_status.cpp |    11 ----                                    
   2 files changed, 60 insertions(+), 37 deletions(-)

Modified: trunk/boost/geometry/algorithms/distance.hpp
==============================================================================
--- trunk/boost/geometry/algorithms/distance.hpp	(original)
+++ trunk/boost/geometry/algorithms/distance.hpp	2011-12-16 18:16:22 EST (Fri, 16 Dec 2011)
@@ -234,6 +234,18 @@
 };
 
 
+// Helper metafunction for default strategy retrieval
+template <typename Geometry1, typename Geometry2>
+struct default_strategy
+    : strategy::distance::services::default_strategy
+          <
+              point_tag,
+              typename point_type<Geometry1>::type,
+              typename point_type<Geometry2>::type
+          >
+{};
+
+
 }} // namespace detail::distance
 #endif // DOXYGEN_NO_DETAIL
 
@@ -242,12 +254,14 @@
 namespace dispatch
 {
 
+
 using strategy::distance::services::return_type;
 
 
 template
 <
-    typename Geometry1, typename Geometry2, typename Strategy,
+    typename Geometry1, typename Geometry2,
+    typename Strategy = typename detail::distance::default_strategy<Geometry1, Geometry2>::type,
     typename Tag1 = typename tag_cast<typename tag<Geometry1>::type, multi_tag>::type,
     typename Tag2 = typename tag_cast<typename tag<Geometry2>::type, multi_tag>::type,
     typename StrategyTag = typename strategy::distance::services::tag<Strategy>::type,
@@ -280,7 +294,8 @@
     Geometry1, Geometry2, Strategy,
     Tag1, Tag2, StrategyTag,
     true
->: distance<Geometry2, Geometry1, Strategy, Tag2, Tag1, StrategyTag, false>
+>
+    : distance<Geometry2, Geometry1, Strategy, Tag2, Tag1, StrategyTag, false>
 {
     static inline typename return_type<Strategy>::type apply(
         Geometry1 const& g1,
@@ -296,6 +311,44 @@
     }
 };
 
+// If reversal is needed and we got the strategy by default, invert it before
+// proceeding to the reversal.
+template
+<
+    typename Geometry1, typename Geometry2,
+    typename Tag1, typename Tag2, typename StrategyTag
+>
+struct distance
+<
+    Geometry1, Geometry2,
+    typename detail::distance::default_strategy<Geometry1, Geometry2>::type,
+    Tag1, Tag2, StrategyTag,
+    true
+>
+    : distance
+          <
+              Geometry2, Geometry1,
+              typename detail::distance::default_strategy<Geometry2, Geometry1>::type,
+              Tag2, Tag1, StrategyTag,
+              false
+          >
+{
+    typedef typename detail::distance::default_strategy<Geometry2, Geometry1>::type Strategy;
+    
+    static inline typename return_type<Strategy>::type apply(
+        Geometry1 const& g1,
+        Geometry2 const& g2,
+        Strategy const& strategy)
+    {
+        return distance
+            <
+                Geometry2, Geometry1, Strategy,
+                Tag2, Tag1, StrategyTag,
+                false
+            >::apply(g2, g1, strategy);
+    }
+};
+
 
 // Point-line version 1, where point-point strategy is specified
 template <typename Point, typename Linestring, typename Strategy>
@@ -491,8 +544,8 @@
 */
 template <typename Geometry1, typename Geometry2, typename Strategy>
 inline typename strategy::distance::services::return_type<Strategy>::type distance(
-                Geometry1 const& geometry1,
-                Geometry2 const& geometry2, Strategy const& strategy)
+                Geometry1 const& geometry1, Geometry2 const& geometry2,
+                Strategy const& strategy)
 {
     concept::check<Geometry1 const>();
     concept::check<Geometry2 const>();
@@ -525,29 +578,8 @@
     concept::check<Geometry1 const>();
     concept::check<Geometry2 const>();
 
-    typedef typename point_type<Geometry1>::type point1_type;
-    typedef typename point_type<Geometry2>::type point2_type;
-
-    // Define a point-point-distance-strategy
-    // for either the normal case, either the reversed case
-    typedef typename boost::mpl::if_c
-        <
-            geometry::reverse_dispatch<Geometry1, Geometry2>::type::value,
-            typename strategy::distance::services::default_strategy
-                <
-                    point_tag,
-                    point2_type,
-                    point1_type
-                >::type,
-            typename strategy::distance::services::default_strategy
-                <
-                    point_tag,
-                    point1_type,
-                    point2_type
-                >::type
-        >::type strategy;
-
-    return distance(geometry1, geometry2, strategy());
+    return distance(geometry1, geometry2,
+                    typename detail::distance::default_strategy<Geometry1, Geometry2>::type());
 }
 
 }} // namespace boost::geometry

Modified: trunk/libs/geometry/doc/src/docutils/tools/support_status/support_status.cpp
==============================================================================
--- trunk/libs/geometry/doc/src/docutils/tools/support_status/support_status.cpp	(original)
+++ trunk/libs/geometry/doc/src/docutils/tools/support_status/support_status.cpp	2011-12-16 18:16:22 EST (Fri, 16 Dec 2011)
@@ -31,16 +31,7 @@
 
 
 template <typename G1, typename G2>
-struct check_distance
-  : boost::geometry::dispatch::distance<
-        G1,
-        G2,
-        typename boost::geometry::strategy::distance::services::default_strategy<
-            boost::geometry::point_tag,
-            G1,
-            G2
-        >::type
-    >
+struct check_distance: boost::geometry::dispatch::distance<G1, G2>
 {};
 
 template <typename G1, typename G2>