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diff --git a/boost/geometry/algorithms/detail/buffer/line_line_intersection.hpp b/boost/geometry/algorithms/detail/buffer/line_line_intersection.hpp
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+++ b/boost/geometry/algorithms/detail/buffer/line_line_intersection.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_ALGORITHMS_DETAIL_BUFFER_LINE_LINE_INTERSECTION_HPP
+#define BOOST_GEOMETRY_ALGORITHMS_DETAIL_BUFFER_LINE_LINE_INTERSECTION_HPP
+
+
+#include <boost/geometry/arithmetic/determinant.hpp>
+#include <boost/geometry/util/math.hpp>
+#include <boost/geometry/strategies/buffer.hpp>
+#include <boost/geometry/algorithms/detail/buffer/parallel_continue.hpp>
+
+namespace boost { namespace geometry
+{
+
+
+#ifndef DOXYGEN_NO_DETAIL
+namespace detail { namespace buffer
+{
+
+
+// TODO: once change this to proper strategy
+// It is different from current segment intersection because these are not segments but lines
+// If we have the Line concept, we can create a strategy
+// Assumes a convex corner
+struct line_line_intersection
+{
+
+    template <typename Point>
+    static inline strategy::buffer::join_selector apply(Point const& pi, Point const& pj,
+        Point const& qi, Point const& qj, Point& ip)
+    {
+        // See http://mathworld.wolfram.com/Line-LineIntersection.html
+        typedef typename coordinate_type<Point>::type coordinate_type;
+
+        coordinate_type const denominator
+            = determinant<coordinate_type>(get<0>(pi) - get<0>(pj),
+                get<1>(pi) - get<1>(pj),
+                get<0>(qi) - get<0>(qj),
+                get<1>(qi) - get<1>(qj));
+
+        // Even if the corner was checked before (so it is convex now), that
+        // was done on the original geometry. This function runs on the buffered
+        // geometries, where sides are generated and might be slightly off. In
+        // Floating Point, that slightly might just exceed the limit and we have
+        // to check it again.
+
+        // For round joins, it will not be used at all.
+        // For miter joints, there is a miter limit
+        // If segments are parallel/collinear we must be distinguish two cases:
+        // they continue each other, or they form a spike
+        if (math::equals(denominator, coordinate_type()))
+        {
+            return parallel_continue(get<0>(qj) - get<0>(qi),
+                                get<1>(qj) - get<1>(qi),
+                                get<0>(pj) - get<0>(pi),
+                                get<1>(pj) - get<1>(pi))
+                ? strategy::buffer::join_continue
+                : strategy::buffer::join_spike
+                ;
+        }
+
+        coordinate_type d1 = determinant<coordinate_type>(get<0>(pi), get<1>(pi), get<0>(pj), get<1>(pj));
+        coordinate_type d2 = determinant<coordinate_type>(get<0>(qi), get<1>(qi), get<0>(qj), get<1>(qj));
+
+        double const multiplier = 1.0 / denominator;
+
+        set<0>(ip, determinant<coordinate_type>(d1, get<0>(pi) - get<0>(pj), d2, get<0>(qi) - get<0>(qj)) * multiplier);
+        set<1>(ip, determinant<coordinate_type>(d1, get<1>(pi) - get<1>(pj), d2, get<1>(qi) - get<1>(qj)) * multiplier);
+
+        return strategy::buffer::join_convex;
+    }
+};
+
+
+}} // namespace detail::buffer
+#endif // DOXYGEN_NO_DETAIL
+
+
+}} // namespace boost::geometry
+
+
+#endif // BOOST_GEOMETRY_ALGORITHMS_DETAIL_BUFFER_LINE_LINE_INTERSECTION_HPP