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diff --git a/boost/geometry/algorithms/detail/turns/compare_turns.hpp b/boost/geometry/algorithms/detail/turns/compare_turns.hpp
new file mode 100644
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+++ b/boost/geometry/algorithms/detail/turns/compare_turns.hpp
@@ -0,0 +1,113 @@
+// Boost.Geometry (aka GGL, Generic Geometry Library)
+
+// Copyright (c) 2014, Oracle and/or its affiliates.
+
+// Licensed under the Boost Software License version 1.0.
+// http://www.boost.org/users/license.html
+
+// Contributed and/or modified by Menelaos Karavelas, on behalf of Oracle
+
+
+#ifndef BOOST_GEOMETRY_ALGORITHMS_DETAIL_TURNS_COMPARE_TURNS_HPP
+#define BOOST_GEOMETRY_ALGORITHMS_DETAIL_TURNS_COMPARE_TURNS_HPP
+
+#include <cstddef>
+#include <functional>
+
+#include <boost/geometry/util/math.hpp>
+#include <boost/geometry/algorithms/detail/overlay/turn_info.hpp>
+
+
+namespace boost { namespace geometry
+{
+
+namespace detail { namespace turns
+{
+
+// TURNS SORTING AND SEARCHING
+
+// sort turns by G1 - source_index == 0 by:
+// seg_id -> fraction -> other_id -> operation
+template
+<
+    typename IdLess = std::less<signed_index_type>,
+    int N = 0, int U = 1, int I = 2, int B = 3, int C = 4, int O = 0,
+    std::size_t OpId = 0
+>
+struct less_seg_fraction_other_op
+{
+    BOOST_STATIC_ASSERT(OpId < 2);
+    static const std::size_t other_op_id = (OpId + 1) % 2;
+
+    template <typename Op>
+    static inline int order_op(Op const& op)
+    {
+        switch (op.operation)
+        {
+        case detail::overlay::operation_none : return N;
+        case detail::overlay::operation_union : return U;
+        case detail::overlay::operation_intersection : return I;
+        case detail::overlay::operation_blocked : return B;
+        case detail::overlay::operation_continue : return C;
+        case detail::overlay::operation_opposite : return O;
+        }
+        return -1;
+    }
+
+    template <typename Op>
+    static inline bool use_operation(Op const& left, Op const& right)
+    {
+        return order_op(left) < order_op(right);
+    }
+
+    template <typename Turn>
+    static inline bool use_other_id(Turn const& left, Turn const& right)
+    {
+        segment_identifier const& left_other_seg_id = left.operations[other_op_id].seg_id;
+        segment_identifier const& right_other_seg_id = right.operations[other_op_id].seg_id;
+
+        if ( left_other_seg_id.multi_index != right_other_seg_id.multi_index )
+        {
+            return left_other_seg_id.multi_index < right_other_seg_id.multi_index;
+        }
+        if ( left_other_seg_id.ring_index != right_other_seg_id.ring_index )
+        {
+            return left_other_seg_id.ring_index != right_other_seg_id.ring_index;
+        }
+        if ( left_other_seg_id.segment_index != right_other_seg_id.segment_index )
+        {
+            return IdLess()(left_other_seg_id.segment_index,
+                            right_other_seg_id.segment_index);
+        }
+        return use_operation(left.operations[OpId], right.operations[OpId]);
+    }
+
+    template <typename Turn>
+    static inline bool use_fraction(Turn const& left, Turn const& right)
+    {
+        return left.operations[OpId].fraction < right.operations[OpId].fraction
+           || ( geometry::math::equals(left.operations[OpId].fraction, right.operations[OpId].fraction) 
+                && use_other_id(left, right)
+              );
+    }
+
+    template <typename Turn>
+    inline bool operator()(Turn const& left, Turn const& right) const
+    {
+        segment_identifier const& sl = left.operations[OpId].seg_id;
+        segment_identifier const& sr = right.operations[OpId].seg_id;
+
+        return sl < sr || ( sl == sr && use_fraction(left, right) );
+    }
+};
+
+
+
+
+
+}} // namespace detail::turns
+
+}} // namespace boost::geometry
+
+
+#endif // BOOST_GEOMETRY_ALGORITHMS_DETAIL_TURNS_COMPARE_TURNS_HPP