Added boost header

test/external/boost/geometry/multi/algorithms/centroid.hpp

@@ -0,0 +1,178 @@
+// Boost.Geometry (aka GGL, Generic Geometry Library)
+
+// Copyright (c) 2007-2011 Barend Gehrels, Amsterdam, the Netherlands.
+// Copyright (c) 2008-2011 Bruno Lalande, Paris, France.
+// Copyright (c) 2009-2011 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_MULTI_ALGORITHMS_CENTROID_HPP
+#define BOOST_GEOMETRY_MULTI_ALGORITHMS_CENTROID_HPP
+
+
+#include <boost/range.hpp>
+
+#include <boost/geometry/algorithms/centroid.hpp>
+#include <boost/geometry/algorithms/num_points.hpp>
+#include <boost/geometry/multi/core/point_type.hpp>
+#include <boost/geometry/multi/algorithms/detail/multi_sum.hpp>
+#include <boost/geometry/multi/algorithms/num_points.hpp>
+
+
+namespace boost { namespace geometry
+{
+
+
+#ifndef DOXYGEN_NO_DETAIL
+namespace detail { namespace centroid
+{
+
+
+/*!
+    \brief Building block of a multi-point, to be used as Policy in the
+        more generec centroid_multi
+*/
+template
+<
+    typename Point,
+    typename Strategy
+>
+struct centroid_multi_point_state
+{
+    static inline void apply(Point const& point,
+            Strategy const& strategy, typename Strategy::state_type& state)
+    {
+        strategy.apply(point, state);
+    }
+};
+
+
+
+/*!
+    \brief Generic implementation which calls a policy to calculate the
+        centroid of the total of its single-geometries
+    \details The Policy is, in general, the single-version, with state. So
+        detail::centroid::centroid_polygon_state is used as a policy for this
+        detail::centroid::centroid_multi
+
+*/
+template
+<
+    typename Multi,
+    typename Point,
+    typename Strategy,
+    typename Policy
+>
+struct centroid_multi
+{
+    static inline void apply(Multi const& multi, Point& centroid,
+            Strategy const& strategy)
+    {
+        // If there is nothing in any of the ranges, it is not possible
+        // to calculate the centroid
+        if (geometry::num_points(multi) == 0)
+        {
+            throw centroid_exception();
+        }
+
+        typename Strategy::state_type state;
+
+        for (typename boost::range_iterator<Multi const>::type
+                it = boost::begin(multi);
+            it != boost::end(multi);
+            ++it)
+        {
+            Policy::apply(*it, strategy, state);
+        }
+        Strategy::result(state, centroid);
+    }
+};
+
+
+
+}} // namespace detail::centroid
+#endif // DOXYGEN_NO_DETAIL
+
+
+
+#ifndef DOXYGEN_NO_DISPATCH
+namespace dispatch
+{
+
+template
+<
+    typename MultiLinestring,
+    typename Point,
+    typename Strategy
+>
+struct centroid<multi_linestring_tag, MultiLinestring, Point,  Strategy>
+    : detail::centroid::centroid_multi
+        <
+            MultiLinestring,
+            Point,
+            Strategy,
+            detail::centroid::centroid_range_state
+                <
+                    typename boost::range_value<MultiLinestring>::type,
+                    closed,
+                    Strategy
+                >
+        >
+{};
+
+template
+<
+    typename MultiPolygon,
+    typename Point,
+    typename Strategy
+>
+struct centroid<multi_polygon_tag, MultiPolygon, Point,  Strategy>
+    : detail::centroid::centroid_multi
+        <
+            MultiPolygon,
+            Point,
+            Strategy,
+            detail::centroid::centroid_polygon_state
+                <
+                    typename boost::range_value<MultiPolygon>::type,
+                    Strategy
+                >
+        >
+{};
+
+
+template
+<
+    typename MultiPoint,
+    typename Point,
+    typename Strategy
+>
+struct centroid<multi_point_tag, MultiPoint, Point,  Strategy>
+    : detail::centroid::centroid_multi
+        <
+            MultiPoint,
+            Point,
+            Strategy,
+            detail::centroid::centroid_multi_point_state
+                <
+                    typename boost::range_value<MultiPoint>::type,
+                    Strategy
+                >
+        >
+{};
+
+
+} // namespace dispatch
+#endif
+
+
+}} // namespace boost::geometry
+
+
+#endif // BOOST_GEOMETRY_MULTI_ALGORITHMS_CENTROID_HPP
+