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+// Boost.Geometry (aka GGL, Generic Geometry Library)
+
+// Copyright (c) 2012-2014 Barend Gehrels, Amsterdam, the Netherlands.
+
+// 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_STRATEGIES_CARTESIAN_BUFFER_JOIN_MITER_HPP
+#define BOOST_GEOMETRY_STRATEGIES_CARTESIAN_BUFFER_JOIN_MITER_HPP
+
+#include <boost/assert.hpp>
+#include <boost/geometry/core/cs.hpp>
+#include <boost/geometry/policies/compare.hpp>
+#include <boost/geometry/util/math.hpp>
+#include <boost/geometry/util/select_most_precise.hpp>
+
+#include <boost/geometry/strategies/buffer.hpp>
+
+
+namespace boost { namespace geometry
+{
+
+namespace strategy { namespace buffer
+{
+
+/*!
+\brief Let the buffer create sharp corners
+\ingroup strategies
+\details This strategy can be used as JoinStrategy for the buffer algorithm.
+    It creates a sharp corners around each convex vertex. It can be applied
+    for (multi)linestrings and (multi)polygons.
+    If corners are sharp by themselves, the miters might become very long. Therefore
+    there is a limit (miter_limit), in terms of the used distance, which limits
+    their length. The miter is not changed to a bevel form (as done in some
+    other software), it is just adapted to the specified miter_limit but keeps
+    its miter form.
+    This strategy is only applicable for Cartesian coordinate systems.
+
+\qbk{
+[heading Example]
+[buffer_join_miter]
+[heading Output]
+[$img/strategies/buffer_join_miter.png]
+[heading See also]
+\* [link geometry.reference.algorithms.buffer.buffer_7_with_strategies buffer (with strategies)]
+\* [link geometry.reference.strategies.strategy_buffer_join_round join_round]
+}
+ */
+class join_miter
+{
+public:
+
+    //! \brief Constructs the strategy
+    //! \param miter_limit The miter limit, to avoid excessively long miters around sharp corners
+    explicit inline join_miter(double miter_limit = 5.0)
+        : m_miter_limit(valid_limit(miter_limit))
+    {}
+
+#ifndef DOXYGEN_SHOULD_SKIP_THIS
+    //! Fills output_range with a sharp shape around a vertex
+    template <typename Point, typename DistanceType, typename RangeOut>
+    inline bool apply(Point const& ip, Point const& vertex,
+                Point const& perp1, Point const& perp2,
+                DistanceType const& buffer_distance,
+                RangeOut& range_out) const
+    {
+        geometry::equal_to<Point> equals;
+        if (equals(ip, vertex))
+        {
+            return false;
+        }
+        if (equals(perp1, perp2))
+        {
+            return false;
+        }
+
+        typedef typename coordinate_type<Point>::type coordinate_type;
+        typedef typename geometry::select_most_precise
+        <
+            coordinate_type,
+            double
+        >::type promoted_type;
+
+        Point p = ip;
+
+        // Check the distance ip-vertex (= miter distance)
+        // (We calculate it manually (not using Pythagoras strategy) to reuse
+        //  dx and dy)
+        coordinate_type const dx = get<0>(p) - get<0>(vertex);
+        coordinate_type const dy = get<1>(p) - get<1>(vertex);
+
+        promoted_type const distance = geometry::math::sqrt(dx * dx + dy * dy);
+
+        promoted_type const max_distance
+            = m_miter_limit * geometry::math::abs(buffer_distance);
+
+        if (distance > max_distance)
+        {
+            BOOST_ASSERT(distance != 0.0);
+
+            promoted_type const proportion = max_distance / distance;
+            set<0>(p, get<0>(vertex) + dx * proportion);
+            set<1>(p, get<1>(vertex) + dy * proportion);
+        }
+
+        range_out.push_back(perp1);
+        range_out.push_back(p);
+        range_out.push_back(perp2);
+        return true;
+    }
+
+    template <typename NumericType>
+    inline NumericType max_distance(NumericType const& distance) const
+    {
+        return distance * m_miter_limit;
+    }
+
+#endif // DOXYGEN_SHOULD_SKIP_THIS
+
+private :
+    double valid_limit(double miter_limit) const
+    {
+        if (miter_limit < 1.0)
+        {
+            // It should always exceed the buffer distance
+            miter_limit = 1.0;
+        }
+        return miter_limit;
+    }
+
+    double m_miter_limit;
+};
+
+}} // namespace strategy::buffer
+
+
+}} // namespace boost::geometry
+
+#endif // BOOST_GEOMETRY_STRATEGIES_CARTESIAN_BUFFER_JOIN_MITER_HPP