// Boost.Geometry (aka GGL, Generic Geometry Library)
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// Copyright (c) 2014-2020, Oracle and/or its affiliates.
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// Contributed and/or modified by Menelaos Karavelas, on behalf of Oracle
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// Contributed and/or modified by Adam Wulkiewicz, on behalf of Oracle
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// Licensed under the Boost Software License version 1.0.
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// http://www.boost.org/users/license.html
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#ifndef BOOST_GEOMETRY_ALGORITHMS_DETAIL_NUM_DISTINCT_CONSECUTIVE_POINTS_HPP
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#define BOOST_GEOMETRY_ALGORITHMS_DETAIL_NUM_DISTINCT_CONSECUTIVE_POINTS_HPP
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#include <algorithm>
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#include <cstddef>
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#include <boost/range/begin.hpp>
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#include <boost/range/end.hpp>
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#include <boost/range/size.hpp>
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namespace boost { namespace geometry
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{
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#ifndef DOXYGEN_NO_DETAIL
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namespace detail
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{
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// returns the number of distinct values in the range;
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// return values are 0u through MaximumNumber, where MaximumNumber
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// corresponds to MaximumNumber or more distinct values
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//
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// FUTURE: take into account topologically closed ranges;
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// add appropriate template parameter(s) to control whether
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// the closing point for topologically closed ranges is to be
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// accounted for separately or not
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template
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<
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typename Range,
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std::size_t MaximumNumber,
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bool AllowDuplicates /* true */,
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typename NotEqualTo
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>
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struct num_distinct_consecutive_points
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{
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static inline std::size_t apply(Range const& range)
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{
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typedef typename boost::range_iterator<Range const>::type iterator;
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std::size_t const size = boost::size(range);
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if ( size < 2u )
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{
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return (size < MaximumNumber) ? size : MaximumNumber;
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}
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iterator current = boost::begin(range);
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std::size_t counter(0);
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do
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{
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++counter;
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iterator next = std::find_if(current,
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boost::end(range),
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NotEqualTo(*current));
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current = next;
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}
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while ( current != boost::end(range) && counter <= MaximumNumber );
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return counter;
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}
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};
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template <typename Range, std::size_t MaximumNumber, typename NotEqualTo>
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struct num_distinct_consecutive_points<Range, MaximumNumber, false, NotEqualTo>
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{
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static inline std::size_t apply(Range const& range)
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{
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std::size_t const size = boost::size(range);
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return (size < MaximumNumber) ? size : MaximumNumber;
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}
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};
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} // namespace detail
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#endif // DOXYGEN_NO_DETAIL
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}} // namespace boost::geometry
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#endif // BOOST_GEOMETRY_ALGORITHMS_DETAIL_NUM_DISTINCT_CONSECUTIVE_POINTS_HPP
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