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diff --git a/boost/geometry/algorithms/detail/direction_code.hpp b/boost/geometry/algorithms/detail/direction_code.hpp
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+++ b/boost/geometry/algorithms/detail/direction_code.hpp
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+// Boost.Geometry (aka GGL, Generic Geometry Library)
+
+// Copyright (c) 2015 Barend Gehrels, Amsterdam, the Netherlands.
+
+// This file was modified by Oracle on 2015.
+// Modifications copyright (c) 2015 Oracle and/or its affiliates.
+
+// Contributed and/or modified by Menelaos Karavelas, 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
+// http://www.boost.org/LICENSE_1_0.txt)
+
+#ifndef BOOST_GEOMETRY_ALGORITHMS_DETAIL_DIRECITON_CODE_HPP
+#define BOOST_GEOMETRY_ALGORITHMS_DETAIL_DIRECITON_CODE_HPP
+
+
+#include <boost/geometry/core/access.hpp>
+#include <boost/geometry/util/math.hpp>
+
+namespace boost { namespace geometry
+{
+
+#ifndef DOXYGEN_NO_DETAIL
+namespace detail
+{
+
+template <std::size_t Index, typename Point1, typename Point2>
+inline int sign_of_difference(Point1 const& point1, Point2 const& point2)
+{
+    return
+        math::equals(geometry::get<Index>(point1), geometry::get<Index>(point2))
+        ?
+        0
+        :
+        (geometry::get<Index>(point1) > geometry::get<Index>(point2) ? 1 : -1);
+}
+
+
+// Gives sense of direction for point p, collinear w.r.t. segment (a,b)
+// Returns -1 if p goes backward w.r.t (a,b), so goes from b in direction of a
+// Returns 1 if p goes forward, so extends (a,b)
+// Returns 0 if p is equal with b, or if (a,b) is degenerate
+// Note that it does not do any collinearity test, that should be done before
+template <typename Point1, typename Point2>
+inline int direction_code(Point1 const& segment_a, Point1 const& segment_b,
+                          const Point2& p)
+{
+    // Suppose segment = (4 3,4 4) and p =(4 2)
+    // Then sign_a1 = 1 and sign_p1 = 1 -> goes backward -> return -1
+
+    int const sign_a0 = sign_of_difference<0>(segment_b, segment_a);
+    int const sign_a1 = sign_of_difference<1>(segment_b, segment_a);
+
+    if (sign_a0 == 0 && sign_a1 == 0)
+    {
+        return 0;
+    }
+
+    int const sign_p0 = sign_of_difference<0>(segment_b, p);
+    int const sign_p1 = sign_of_difference<1>(segment_b, p);
+
+    if (sign_p0 == 0 && sign_p1 == 0)
+    {
+        return 0;
+    }
+
+    return sign_a0 == sign_p0 && sign_a1 == sign_p1 ? -1 : 1;
+}
+
+
+} // namespace detail
+#endif //DOXYGEN_NO_DETAIL
+
+
+
+}} // namespace boost::geometry
+
+#endif // BOOST_GEOMETRY_ALGORITHMS_DETAIL_DIRECITON_CODE_HPP