1 files changed, 78 insertions, 0 deletions
diff --git a/boost/geometry/algorithms/detail/turns/filter_continue_turns.hpp b/boost/geometry/algorithms/detail/turns/filter_continue_turns.hpp
new file mode 100644
index 0000000000..17fbd65ddc
--- /dev/null
+++ b/boost/geometry/algorithms/detail/turns/filter_continue_turns.hpp
@@ -0,0 +1,78 @@
+// 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_FILTER_CONTINUE_TURNS_HPP
+#define BOOST_GEOMETRY_ALGORITHMS_DETAIL_TURNS_FILTER_CONTINUE_TURNS_HPP
+
+#include <algorithm>
+#include <boost/geometry/algorithms/detail/overlay/turn_info.hpp>
+
+namespace boost { namespace geometry
+{
+
+namespace detail { namespace turns
+{
+
+
+template <typename Turns, bool Enable>
+struct filter_continue_turns
+{
+    static inline void apply(Turns&) {}
+};
+
+
+template <typename Turns>
+class filter_continue_turns<Turns, true>
+{
+private:
+    class IsContinueTurn
+    {
+    private:
+        template <typename Operation>
+        inline bool is_continue_or_opposite(Operation const& operation) const
+        {
+            return operation == detail::overlay::operation_continue
+                || operation == detail::overlay::operation_opposite;
+        }
+
+    public:
+        template <typename Turn>
+        bool operator()(Turn const& turn) const
+        {
+            if ( turn.method != detail::overlay::method_collinear
+                 && turn.method != detail::overlay::method_equal )
+            {
+                return false;
+            }
+
+            return is_continue_or_opposite(turn.operations[0].operation)
+                && is_continue_or_opposite(turn.operations[1].operation);
+        }
+    };
+
+
+public:
+    static inline void apply(Turns& turns)
+    {
+        turns.erase( std::remove_if(turns.begin(), turns.end(),
+                                    IsContinueTurn()),
+                     turns.end()
+                     );
+    }
+};
+
+
+}} // namespace detail::turns
+
+}} // namespect boost::geometry
+
+
+
+#endif // BOOST_GEOMETRY_ALGORITHMS_DETAIL_TURNS_FILTER_CONTINUE_TURNS_HPP