Imported Upstream version 1.57.0upstream/1.57.0

1 files changed, 95 insertions, 0 deletions

diff --git a/boost/geometry/algorithms/detail/single_geometry.hpp b/boost/geometry/algorithms/detail/single_geometry.hpp
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+++ b/boost/geometry/algorithms/detail/single_geometry.hpp
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+// Boost.Geometry (aka GGL, Generic Geometry Library)
+
+// Copyright (c) 2007-2012 Barend Gehrels, Amsterdam, the Netherlands.
+
+// This file was modified by Oracle on 2013, 2014.
+// Modifications copyright (c) 2013-2014, Oracle and/or its affiliates.
+
+// 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)
+
+// Contributed and/or modified by Adam Wulkiewicz, on behalf of Oracle
+
+#ifndef BOOST_GEOMETRY_ALGORITHMS_DETAIL_SINGLE_GEOMETRY_HPP
+#define BOOST_GEOMETRY_ALGORITHMS_DETAIL_SINGLE_GEOMETRY_HPP
+
+#include <boost/type_traits/is_base_of.hpp>
+#include <boost/geometry/core/tag.hpp>
+#include <boost/geometry/util/range.hpp>
+
+namespace boost { namespace geometry {
+
+#ifndef DOXYGEN_NO_DISPATCH
+namespace detail_dispatch {
+
+// Returns single geometry by Id
+// for single geometries returns the geometry itself
+template <typename Geometry,
+          bool IsMulti = boost::is_base_of
+                            <
+                                multi_tag,
+                                typename geometry::tag<Geometry>::type
+                            >::value
+>
+struct single_geometry
+{
+    typedef Geometry & return_type;
+
+    template <typename Id>
+    static inline return_type apply(Geometry & g, Id const& ) { return g; }
+};
+
+// for multi geometries returns one of the stored single geometries
+template <typename Geometry>
+struct single_geometry<Geometry, true>
+{
+    typedef typename boost::mpl::if_c
+        <
+            boost::is_const<Geometry>::value,
+            typename boost::range_value<Geometry>::type const&,
+            typename boost::range_value<Geometry>::type
+        >::type return_type;
+
+    template <typename Id>
+    static inline return_type apply(Geometry & g, Id const& id)
+    {
+        BOOST_ASSERT(id.multi_index >= 0);
+        return range::at(g, id.multi_index);
+    }
+};
+
+} // namespace detail_dispatch
+#endif // DOXYGEN_NO_DISPATCH
+
+#ifndef DOXYGEN_NO_DETAIL
+namespace detail {
+
+template <typename Geometry>
+struct single_geometry_return_type
+{
+    typedef typename detail_dispatch::single_geometry<Geometry>::return_type type;
+};
+
+template <typename Geometry, typename Id>
+inline
+typename single_geometry_return_type<Geometry>::type
+single_geometry(Geometry & geometry, Id const& id)
+{
+    return detail_dispatch::single_geometry<Geometry>::apply(geometry, id);
+}
+
+template <typename Geometry, typename Id>
+inline
+typename single_geometry_return_type<Geometry const>::type
+single_geometry(Geometry const& geometry, Id const& id)
+{
+    return detail_dispatch::single_geometry<Geometry const>::apply(geometry, id);
+}
+
+} // namespace detail
+#endif // DOXYGEN_NO_DETAIL
+
+}} // namespace boost::geometry
+
+#endif // BOOST_GEOMETRY_ALGORITHMS_DETAIL_SINGLE_GEOMETRY_HPP