1 files changed, 49 insertions, 27 deletions

diff --git a/boost/geometry/algorithms/detail/point_is_spike_or_equal.hpp b/boost/geometry/algorithms/detail/point_is_spike_or_equal.hpp
index 607ba81531..b8ea5e30e6 100644
--- a/boost/geometry/algorithms/detail/point_is_spike_or_equal.hpp
+++ b/boost/geometry/algorithms/detail/point_is_spike_or_equal.hpp
@@ -5,10 +5,11 @@
 // Copyright (c) 2009-2015 Mateusz Loskot, London, UK.
 // Copyright (c) 2013-2015 Adam Wulkiewicz, Lodz, Poland.
 
-// This file was modified by Oracle on 2015.
-// Modifications copyright (c) 2015 Oracle and/or its affiliates.
+// This file was modified by Oracle on 2015, 2017.
+// Modifications copyright (c) 2015-2017 Oracle and/or its affiliates.
 
 // Contributed and/or modified by Menelaos Karavelas, on behalf of Oracle
+// Contributed and/or modified by Adam Wulkiewicz, on behalf of Oracle
 
 // Use, modification and distribution is subject to the Boost Software License,
 // Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
@@ -19,11 +20,13 @@
 
 #include <boost/geometry/algorithms/detail/direction_code.hpp>
 #include <boost/geometry/algorithms/detail/recalculate.hpp>
+#include <boost/geometry/core/cs.hpp>
 #include <boost/geometry/policies/robustness/robust_point_type.hpp>
 #include <boost/geometry/strategies/side.hpp>
 #include <boost/geometry/util/condition.hpp>
 #include <boost/geometry/util/math.hpp>
 
+
 namespace boost { namespace geometry
 {
 
@@ -32,6 +35,26 @@ namespace boost { namespace geometry
 namespace detail
 {
 
+template <typename Point1, typename Point2, typename Point3>
+inline bool collinear_point_is_spike_or_equal(Point1 const& last_point,
+                                                Point2 const& segment_a,
+                                                Point3 const& segment_b)
+{
+    // Check if segment is equal
+    int const sgn_x1 = sign_of_difference<0>(last_point, segment_b);
+    int const sgn_y1 = sign_of_difference<1>(last_point, segment_b);
+    if (sgn_x1 == 0 && sgn_y1 == 0)
+    {
+        return true;
+    }
+
+    // Check if segment moves forward
+    int const sgn_x2 = sign_of_difference<0>(segment_b, segment_a);
+    int const sgn_y2 = sign_of_difference<1>(segment_b, segment_a);
+
+    return sgn_x1 != sgn_x2 || sgn_y1 != sgn_y2;
+}
+
 // Checks if a point ("last_point") causes a spike w.r.t.
 // the specified two other points (segment_a, segment_b)
 //
@@ -42,33 +65,29 @@ namespace detail
 // So specify last point first, then (a,b)
 // The segment's orientation does matter: if lp is to the right of b
 // no spike is reported
-template <typename Point1, typename Point2, typename Point3>
-static inline bool point_is_spike_or_equal(Point1 const& last_point,
-            Point2 const& segment_a,
-            Point3 const& segment_b)
+template
+<
+    typename Point1, typename Point2, typename Point3,
+    typename SideStrategy
+>
+static inline bool point_is_spike_or_equal(Point1 const& last_point, // prev | back
+                                           Point2 const& segment_a,  // next | back - 2
+                                           Point3 const& segment_b,  // curr | back - 1 | spike's vertex
+                                           SideStrategy const& strategy)
 {
-    typedef typename strategy::side::services::default_strategy
-    <
-        typename cs_tag<Point1>::type
-    >::type side_strategy;
-
-    int const side = side_strategy::apply(last_point, segment_a, segment_b);
+    int const side = strategy.apply(segment_a, segment_b, last_point);
     if (side == 0)
     {
         // Last point is collinear w.r.t previous segment.
-        // Check if it is equal
-        int const sgn_x1 = sign_of_difference<0>(last_point, segment_b);
-        int const sgn_y1 = sign_of_difference<1>(last_point, segment_b);
-        if (sgn_x1 == 0 && sgn_y1 == 0)
-        {
-            return true;
-        }
-
-        // Check if it moves forward
-        int const sgn_x2 = sign_of_difference<0>(segment_b, segment_a);
-        int const sgn_y2 = sign_of_difference<1>(segment_b, segment_a);
-
-        return sgn_x1 != sgn_x2 || sgn_y1 != sgn_y2;
+#ifdef BOOST_GEOMETRY_ENABLE_POINT_IS_SPIKE_OR_EQUAL_TEST
+        bool r1 = collinear_point_is_spike_or_equal(last_point, segment_a, segment_b);
+        bool r2 = direction_code(segment_a, segment_b, last_point) < 1;
+        if (r1 != r2)
+            std::cout << "spike detection failure with: " << r1 << " " << r2 << std::endl;
+        return r2;
+#else
+        return direction_code(segment_a, segment_b, last_point) < 1;
+#endif
     }
     return false;
 }
@@ -78,14 +97,16 @@ template
     typename Point1,
     typename Point2,
     typename Point3,
+    typename SideStrategy,
     typename RobustPolicy
 >
 static inline bool point_is_spike_or_equal(Point1 const& last_point,
             Point2 const& segment_a,
             Point3 const& segment_b,
+            SideStrategy const& strategy,
             RobustPolicy const& robust_policy)
 {
-    if (point_is_spike_or_equal(last_point, segment_a, segment_b))
+    if (point_is_spike_or_equal(last_point, segment_a, segment_b, strategy))
     {
         return true;
     }
@@ -111,7 +132,8 @@ static inline bool point_is_spike_or_equal(Point1 const& last_point,
         (
             last_point_rob,
             segment_a_rob,
-            segment_b_rob
+            segment_b_rob,
+            strategy
         );
 }