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diff --git a/boost/geometry/strategies/cartesian/buffer_side_straight.hpp b/boost/geometry/strategies/cartesian/buffer_side_straight.hpp
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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_SIDE_STRAIGHT_HPP
+#define BOOST_GEOMETRY_STRATEGIES_CARTESIAN_BUFFER_SIDE_STRAIGHT_HPP
+
+#include <cstddef>
+
+#include <boost/geometry/core/coordinate_type.hpp>
+#include <boost/geometry/core/access.hpp>
+#include <boost/geometry/util/math.hpp>
+#include <boost/geometry/util/select_most_precise.hpp>
+
+#include <boost/geometry/strategies/buffer.hpp>
+#include <boost/geometry/strategies/side.hpp>
+
+
+
+namespace boost { namespace geometry
+{
+
+namespace strategy { namespace buffer
+{
+
+
+
+/*!
+\brief Let the buffer use straight sides along segments (the default)
+\ingroup strategies
+\details This strategy can be used as SideStrategy for the buffer algorithm.
+    It is currently the only provided strategy for this purpose
+
+\qbk{
+[heading Example]
+See the examples for other buffer strategies\, for example
+[link geometry.reference.strategies.strategy_buffer_join_round join_round]
+[heading See also]
+\* [link geometry.reference.algorithms.buffer.buffer_7_with_strategies buffer (with strategies)]
+}
+ */
+class side_straight
+{
+public :
+#ifndef DOXYGEN_SHOULD_SKIP_THIS
+    template
+    <
+        typename Point,
+        typename OutputRange,
+        typename DistanceStrategy
+    >
+    static inline void apply(
+                Point const& input_p1, Point const& input_p2,
+                strategy::buffer::buffer_side_selector side,
+                DistanceStrategy const& distance,
+                OutputRange& output_range)
+    {
+        typedef typename coordinate_type<Point>::type coordinate_type;
+        typedef typename geometry::select_most_precise
+        <
+            coordinate_type,
+            double
+        >::type promoted_type;
+
+        // Generate a block along (left or right of) the segment
+
+        // Simulate a vector d (dx,dy)
+        coordinate_type const dx = get<0>(input_p2) - get<0>(input_p1);
+        coordinate_type const dy = get<1>(input_p2) - get<1>(input_p1);
+
+        // For normalization [0,1] (=dot product d.d, sqrt)
+        promoted_type const length = geometry::math::sqrt(dx * dx + dy * dy);
+
+        if (geometry::math::equals(length, 0))
+        {
+            // Coordinates are simplified and therefore most often not equal.
+            // But if simplify is skipped, or for lines with two
+            // equal points, length is 0 and we cannot generate output.
+            return;
+        }
+
+        // Generate the normalized perpendicular p, to the left (ccw)
+        promoted_type const px = -dy / length;
+        promoted_type const py = dx / length;
+
+        promoted_type const d = distance.apply(input_p1, input_p2, side);
+
+        output_range.resize(2);
+
+        set<0>(output_range.front(), get<0>(input_p1) + px * d);
+        set<1>(output_range.front(), get<1>(input_p1) + py * d);
+        set<0>(output_range.back(), get<0>(input_p2) + px * d);
+        set<1>(output_range.back(), get<1>(input_p2) + py * d);
+    }
+#endif // DOXYGEN_SHOULD_SKIP_THIS
+};
+
+
+}} // namespace strategy::buffer
+
+}} // namespace boost::geometry
+
+#endif // BOOST_GEOMETRY_STRATEGIES_CARTESIAN_BUFFER_SIDE_STRAIGHT_HPP