detail/is_valid/has_duplicates.hpp

0001 // Boost.Geometry (aka GGL, Generic Geometry Library)
0002
0003 // Copyright (c) 2014-2021, Oracle and/or its affiliates.
0004
0005 // Contributed and/or modified by Menelaos Karavelas, on behalf of Oracle
0006 // Contributed and/or modified by Adam Wulkiewicz, on behalf of Oracle
0007
0008 // Licensed under the Boost Software License version 1.0.
0009 // http://www.boost.org/users/license.html
0010
0011 #ifndef BOOST_GEOMETRY_ALGORITHMS_DETAIL_IS_VALID_HAS_DUPLICATES_HPP
0012 #define BOOST_GEOMETRY_ALGORITHMS_DETAIL_IS_VALID_HAS_DUPLICATES_HPP
0013
0014 #include <boost/core/ignore_unused.hpp>
0015 #include <boost/range/begin.hpp>
0016 #include <boost/range/end.hpp>
0017 #include <boost/range/size.hpp>
0018
0019 #include <boost/geometry/core/closure.hpp>
0020
0021 #include <boost/geometry/policies/compare.hpp>
0022 #include <boost/geometry/policies/is_valid/default_policy.hpp>
0023
0024 #include <boost/geometry/views/closeable_view.hpp>
0025 #include <boost/geometry/algorithms/validity_failure_type.hpp>
0026
0027
0028 namespace boost { namespace geometry
0029 {
0030
0031
0032 #ifndef DOXYGEN_NO_DETAIL
0033 namespace detail { namespace is_valid
0034 {
0035
0036 template <typename Range>
0037 struct has_duplicates
0038 {
0039     template <typename VisitPolicy, typename Strategy>
0040     static inline bool apply(Range const& range, VisitPolicy& visitor,
0041                              Strategy const& )
0042     {
0043         boost::ignore_unused(visitor);
0044
0045         detail::closed_view<Range const> const view(range);
0046
0047         if ( boost::size(view) < 2 )
0048         {
0049             return ! visitor.template apply<no_failure>();
0050         }
0051
0052         geometry::equal_to
0053             <
0054                 typename boost::range_value<Range>::type,
0055                 -1,
0056                 typename Strategy::cs_tag
0057             > equal;
0058
0059         auto it = boost::begin(view);
0060         auto const end = boost::end(view);
0061         auto next = it;
0062         for (++next; next != end; ++it, ++next)
0063         {
0064             if ( equal(*it, *next) )
0065             {
0066                 return ! visitor.template apply<failure_duplicate_points>(*it);
0067             }
0068         }
0069         return ! visitor.template apply<no_failure>();
0070     }
0071 };
0072
0073
0074
0075 }} // namespace detail::is_valid
0076 #endif // DOXYGEN_NO_DETAIL
0077
0078
0079 }} // namespace boost::geometry
0080
0081
0082
0083 #endif // BOOST_GEOMETRY_ALGORITHMS_DETAIL_IS_VALID_HAS_DUPLICATES_HPP