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