Imported Upstream version 1.49.0upstream/1.49.0

1 files changed, 167 insertions, 0 deletions

diff --git a/boost/geometry/algorithms/buffer.hpp b/boost/geometry/algorithms/buffer.hpp
new file mode 100644
index 0000000000..e22e36addc
--- /dev/null
+++ b/boost/geometry/algorithms/buffer.hpp
@@ -0,0 +1,167 @@
+// Boost.Geometry (aka GGL, Generic Geometry Library)
+
+// Copyright (c) 2007-2012 Barend Gehrels, Amsterdam, the Netherlands.
+// Copyright (c) 2008-2012 Bruno Lalande, Paris, France.
+// Copyright (c) 2009-2012 Mateusz Loskot, London, UK.
+
+// Parts of Boost.Geometry are redesigned from Geodan's Geographic Library
+// (geolib/GGL), copyright (c) 1995-2010 Geodan, 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_BUFFER_HPP
+#define BOOST_GEOMETRY_ALGORITHMS_BUFFER_HPP
+
+#include <cstddef>
+
+#include <boost/numeric/conversion/cast.hpp>
+
+
+#include <boost/geometry/algorithms/clear.hpp>
+#include <boost/geometry/algorithms/detail/disjoint.hpp>
+#include <boost/geometry/arithmetic/arithmetic.hpp>
+#include <boost/geometry/geometries/concepts/check.hpp>
+#include <boost/geometry/geometries/segment.hpp>
+#include <boost/geometry/util/math.hpp>
+
+
+namespace boost { namespace geometry
+{
+
+
+#ifndef DOXYGEN_NO_DETAIL
+namespace detail { namespace buffer
+{
+
+template <typename BoxIn, typename BoxOut, typename T, std::size_t C, std::size_t D, std::size_t N>
+struct box_loop
+{
+    typedef typename coordinate_type<BoxOut>::type coordinate_type;
+
+    static inline void apply(BoxIn const& box_in, T const& distance, BoxOut& box_out)
+    {
+        coordinate_type d = distance;
+        set<C, D>(box_out, get<C, D>(box_in) + d);
+        box_loop<BoxIn, BoxOut, T, C, D + 1, N>::apply(box_in, distance, box_out);
+    }
+};
+
+template <typename BoxIn, typename BoxOut, typename T, std::size_t C, std::size_t N>
+struct box_loop<BoxIn, BoxOut, T, C, N, N>
+{
+    static inline void apply(BoxIn const&, T const&, BoxOut&) {}
+};
+
+// Extends a box with the same amount in all directions
+template<typename BoxIn, typename BoxOut, typename T>
+inline void buffer_box(BoxIn const& box_in, T const& distance, BoxOut& box_out)
+{
+    assert_dimension_equal<BoxIn, BoxOut>();
+
+    static const std::size_t N = dimension<BoxIn>::value;
+
+    box_loop<BoxIn, BoxOut, T, min_corner, 0, N>::apply(box_in, -distance, box_out);
+    box_loop<BoxIn, BoxOut, T, max_corner, 0, N>::apply(box_in, distance, box_out);
+}
+
+
+
+}} // namespace detail::buffer
+#endif // DOXYGEN_NO_DETAIL
+
+#ifndef DOXYGEN_NO_DISPATCH
+namespace dispatch
+{
+
+template <typename TagIn, typename TagOut, typename Input, typename T, typename Output>
+struct buffer {};
+
+
+template <typename BoxIn, typename T, typename BoxOut>
+struct buffer<box_tag, box_tag, BoxIn, T, BoxOut>
+{
+    static inline void apply(BoxIn const& box_in, T const& distance,
+                T const& , BoxIn& box_out)
+    {
+        detail::buffer::buffer_box(box_in, distance, box_out);
+    }
+};
+
+// Many things to do. Point is easy, other geometries require self intersections
+// For point, note that it should output as a polygon (like the rest). Buffers
+// of a set of geometries are often lateron combined using a "dissolve" operation.
+// Two points close to each other get a combined kidney shaped buffer then.
+
+} // namespace dispatch
+#endif // DOXYGEN_NO_DISPATCH
+
+
+/*!
+\brief \brief_calc{buffer}
+\ingroup buffer
+\details \details_calc{buffer, \det_buffer}.
+\tparam Input \tparam_geometry
+\tparam Output \tparam_geometry
+\tparam Distance \tparam_numeric
+\param geometry_in \param_geometry
+\param geometry_out \param_geometry
+\param distance The distance to be used for the buffer
+\param chord_length (optional) The length of the chord's in the generated arcs around points or bends
+\note Currently only implemented for box, the trivial case, but still useful
+
+\qbk{[include reference/algorithms/buffer.qbk]}
+ */
+template <typename Input, typename Output, typename Distance>
+inline void buffer(Input const& geometry_in, Output& geometry_out,
+            Distance const& distance, Distance const& chord_length = -1)
+{
+    concept::check<Input const>();
+    concept::check<Output>();
+
+    dispatch::buffer
+        <
+            typename tag<Input>::type,
+            typename tag<Output>::type,
+            Input,
+            Distance,
+            Output
+        >::apply(geometry_in, distance, chord_length, geometry_out);
+}
+
+/*!
+\brief \brief_calc{buffer}
+\ingroup buffer
+\details \details_calc{return_buffer, \det_buffer}. \details_return{buffer}.
+\tparam Input \tparam_geometry
+\tparam Output \tparam_geometry
+\tparam Distance \tparam_numeric
+\param geometry \param_geometry
+\param distance The distance to be used for the buffer
+\param chord_length (optional) The length of the chord's in the generated arcs around points or bends
+\return \return_calc{buffer}
+ */
+template <typename Output, typename Input, typename T>
+Output return_buffer(Input const& geometry, T const& distance, T const& chord_length = -1)
+{
+    concept::check<Input const>();
+    concept::check<Output>();
+
+    Output geometry_out;
+
+    dispatch::buffer
+        <
+            typename tag<Input>::type,
+            typename tag<Output>::type,
+            Input,
+            T,
+            Output
+        >::apply(geometry, distance, chord_length, geometry_out);
+
+    return geometry_out;
+}
+
+}} // namespace boost::geometry
+
+#endif // BOOST_GEOMETRY_ALGORITHMS_BUFFER_HPP