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Diffstat (limited to 'boost/geometry/algorithms/detail/envelope/range.hpp')
| -rw-r--r-- | boost/geometry/algorithms/detail/envelope/range.hpp | 179 |
1 files changed, 179 insertions, 0 deletions
diff --git a/boost/geometry/algorithms/detail/envelope/range.hpp b/boost/geometry/algorithms/detail/envelope/range.hpp new file mode 100644 index 0000000000..63b518114b --- /dev/null +++ b/boost/geometry/algorithms/detail/envelope/range.hpp @@ -0,0 +1,179 @@ +// Boost.Geometry (aka GGL, Generic Geometry Library) + +// Copyright (c) 2007-2015 Barend Gehrels, Amsterdam, the Netherlands. +// Copyright (c) 2008-2015 Bruno Lalande, Paris, France. +// Copyright (c) 2009-2015 Mateusz Loskot, London, UK. + +// This file was modified by Oracle on 2015. +// Modifications copyright (c) 2015, Oracle and/or its affiliates. + +// Contributed and/or modified by Menelaos Karavelas, on behalf of Oracle + +// Parts of Boost.Geometry are redesigned from Geodan's Geographic Library +// (geolib/GGL), copyright (c) 1995-2010 Geodan, Amsterdam, the Netherlands. + +// Distributed under 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_ENVELOPE_RANGE_HPP +#define BOOST_GEOMETRY_ALGORITHMS_DETAIL_ENVELOPE_RANGE_HPP + +#include <iterator> +#include <vector> + +#include <boost/range.hpp> + +#include <boost/geometry/core/coordinate_dimension.hpp> + +#include <boost/geometry/util/range.hpp> + +#include <boost/geometry/algorithms/is_empty.hpp> + +#include <boost/geometry/algorithms/detail/envelope/initialize.hpp> +#include <boost/geometry/algorithms/detail/envelope/range_of_boxes.hpp> + +#include <boost/geometry/algorithms/detail/expand/box.hpp> +#include <boost/geometry/algorithms/detail/expand/point.hpp> +#include <boost/geometry/algorithms/detail/expand/segment.hpp> + +#include <boost/geometry/algorithms/dispatch/envelope.hpp> + + +namespace boost { namespace geometry +{ + +#ifndef DOXYGEN_NO_DETAIL +namespace detail { namespace envelope +{ + + +// implementation for simple ranges +struct envelope_range +{ + template <typename Iterator, typename Box> + static inline void apply(Iterator first, Iterator last, Box& mbr) + { + typedef typename std::iterator_traits<Iterator>::value_type value_type; + + // initialize MBR + initialize<Box, 0, dimension<Box>::value>::apply(mbr); + + Iterator it = first; + if (it != last) + { + // initialize box with first element in range + dispatch::envelope<value_type>::apply(*it, mbr); + + // consider now the remaining elements in the range (if any) + for (++it; it != last; ++it) + { + dispatch::expand<Box, value_type>::apply(mbr, *it); + } + } + } + + template <typename Range, typename Box> + static inline void apply(Range const& range, Box& mbr) + { + return apply(boost::begin(range), boost::end(range), mbr); + } +}; + + +// implementation for multi-ranges +template <typename EnvelopePolicy> +struct envelope_multi_range +{ + template <typename MultiRange, typename Box> + static inline void apply(MultiRange const& multirange, Box& mbr) + { + typedef typename boost::range_iterator + < + MultiRange const + >::type iterator_type; + + bool initialized = false; + for (iterator_type it = boost::begin(multirange); + it != boost::end(multirange); + ++it) + { + if (! geometry::is_empty(*it)) + { + if (initialized) + { + Box helper_mbr; + EnvelopePolicy::apply(*it, helper_mbr); + + dispatch::expand<Box, Box>::apply(mbr, helper_mbr); + } + else + { + // compute the initial envelope + EnvelopePolicy::apply(*it, mbr); + initialized = true; + } + } + } + + if (! initialized) + { + // if not already initialized, initialize MBR + initialize<Box, 0, dimension<Box>::value>::apply(mbr); + } + } +}; + + +// implementation for multi-range on a spheroid (longitude is periodic) +template <typename EnvelopePolicy> +struct envelope_multi_range_on_spheroid +{ + template <typename MultiRange, typename Box> + static inline void apply(MultiRange const& multirange, Box& mbr) + { + typedef typename boost::range_iterator + < + MultiRange const + >::type iterator_type; + + // due to the periodicity of longitudes we need to compute the boxes + // of all the single geometries and keep them in a container + std::vector<Box> boxes; + for (iterator_type it = boost::begin(multirange); + it != boost::end(multirange); + ++it) + { + if (! geometry::is_empty(*it)) + { + Box helper_box; + EnvelopePolicy::apply(*it, helper_box); + boxes.push_back(helper_box); + } + } + + // now we need to compute the envelope of the range of boxes + // (cannot be done in an incremental fashion as in the + // Cartesian coordinate system) + // if all single geometries are empty no boxes have been found + // and the MBR is simply initialized + if (! boxes.empty()) + { + envelope_range_of_boxes::apply(boxes, mbr); + } + else + { + initialize<Box, 0, dimension<Box>::value>::apply(mbr); + } + + } +}; + + +}} // namespace detail::envelope +#endif // DOXYGEN_NO_DETAIL + + +}} // namespace boost::geometry + +#endif // BOOST_GEOMETRY_ALGORITHMS_DETAIL_ENVELOPE_RANGE_HPP |