1 files changed, 38 insertions, 18 deletions

diff --git a/boost/geometry/formulas/elliptic_arc_length.hpp b/boost/geometry/formulas/elliptic_arc_length.hpp
index 75881f3d0d..65c8f60226 100644
--- a/boost/geometry/formulas/elliptic_arc_length.hpp
+++ b/boost/geometry/formulas/elliptic_arc_length.hpp
@@ -14,7 +14,6 @@
 #include <boost/math/constants/constants.hpp>
 
 #include <boost/geometry/core/radius.hpp>
-#include <boost/geometry/core/srs.hpp>
 
 #include <boost/geometry/util/condition.hpp>
 #include <boost/geometry/util/math.hpp>
@@ -46,14 +45,45 @@ public :
         bool meridian;
     };
 
+    template <typename T>
+    static bool meridian_not_crossing_pole(T lat1, T lat2, CT diff)
+    {
+        CT half_pi = math::pi<CT>()/CT(2);
+        return math::equals(diff, CT(0)) ||
+                    (math::equals(lat2, half_pi) && math::equals(lat1, -half_pi));
+    }
+
+    static bool meridian_crossing_pole(CT diff)
+    {
+        return math::equals(math::abs(diff), math::pi<CT>());
+    }
+
+
+    template <typename T, typename Spheroid>
+    static CT meridian_not_crossing_pole_dist(T lat1, T lat2, Spheroid const& spheroid)
+    {
+        return math::abs(apply(lat2, spheroid) - apply(lat1, spheroid));
+    }
+
+    template <typename T, typename Spheroid>
+    static CT meridian_crossing_pole_dist(T lat1, T lat2, Spheroid const& spheroid)
+    {
+        CT c0 = 0;
+        CT half_pi = math::pi<CT>()/CT(2);
+        CT lat_sign = 1;
+        if (lat1+lat2 < c0)
+        {
+            lat_sign = CT(-1);
+        }
+        return math::abs(lat_sign * CT(2) * apply(half_pi, spheroid)
+                         - apply(lat1, spheroid) - apply(lat2, spheroid));
+    }
+
     template <typename T, typename Spheroid>
     static result apply(T lon1, T lat1, T lon2, T lat2, Spheroid const& spheroid)
     {
         result res;
 
-        CT c0 = 0;
-        CT pi = math::pi<CT>();
-        CT half_pi = pi/CT(2);
         CT diff = geometry::math::longitude_distance_signed<geometry::radian>(lon1, lon2);
 
         if (lat1 > lat2)
@@ -61,24 +91,14 @@ public :
             std::swap(lat1, lat2);
         }
 
-        if ( math::equals(diff, c0) ||
-            (math::equals(lat2, half_pi) && math::equals(lat1, -half_pi)) )
+        if ( meridian_not_crossing_pole(lat1, lat2, diff) )
         {
-            // single meridian not crossing pole
-            res.distance = apply(lat2, spheroid) - apply(lat1, spheroid);
+            res.distance = meridian_not_crossing_pole_dist(lat1, lat2, spheroid);
             res.meridian = true;
         }
-
-        if (math::equals(math::abs(diff), pi))
+        else if ( meridian_crossing_pole(diff) )
         {
-            // meridian crosses pole
-            CT lat_sign = 1;
-            if (lat1+lat2 < c0)
-            {
-                lat_sign = CT(-1);
-            }
-            res.distance = math::abs(lat_sign * CT(2) * apply(half_pi, spheroid)
-                               - apply(lat1, spheroid) - apply(lat2, spheroid));
+            res.distance = meridian_crossing_pole_dist(lat1, lat2, spheroid);
             res.meridian = true;
         }
         return res;