1 files changed, 139 insertions, 0 deletions
diff --git a/boost/geometry/algorithms/detail/is_valid/has_spikes.hpp b/boost/geometry/algorithms/detail/is_valid/has_spikes.hpp
new file mode 100644
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+++ b/boost/geometry/algorithms/detail/is_valid/has_spikes.hpp
@@ -0,0 +1,139 @@
+// 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_IS_VALID_HAS_SPIKES_HPP
+#define BOOST_GEOMETRY_ALGORITHMS_DETAIL_IS_VALID_HAS_SPIKES_HPP
+
+#include <algorithm>
+
+#include <boost/range.hpp>
+
+#include <boost/geometry/core/point_type.hpp>
+
+#include <boost/geometry/util/range.hpp>
+
+#include <boost/geometry/views/closeable_view.hpp>
+
+#include <boost/geometry/algorithms/equals.hpp>
+#include <boost/geometry/algorithms/detail/point_is_spike_or_equal.hpp>
+
+
+namespace boost { namespace geometry
+{
+
+
+#ifndef DOXYGEN_NO_DETAIL
+namespace detail { namespace is_valid
+{
+
+template <typename Point>
+struct equal_to
+{
+    Point const& m_point;
+
+    equal_to(Point const& point)
+        : m_point(point)
+    {}
+
+    template <typename OtherPoint>
+    inline bool operator()(OtherPoint const& other) const
+    {
+        return geometry::equals(m_point, other);
+    }
+};
+
+template <typename Point>
+struct not_equal_to
+{
+    Point const& m_point;
+
+    not_equal_to(Point const& point)
+        : m_point(point)
+    {}
+
+    template <typename OtherPoint>
+    inline bool operator()(OtherPoint const& other) const
+    {
+        return !geometry::equals(other, m_point);
+    }
+};
+
+
+
+template <typename Range, closure_selector Closure>
+struct has_spikes
+{
+    static inline bool apply(Range const& range)
+    {
+        typedef not_equal_to<typename point_type<Range>::type> not_equal;
+
+        typedef typename closeable_view<Range const, Closure>::type view_type;
+        typedef typename boost::range_iterator<view_type const>::type iterator; 
+
+        view_type const view(range);
+
+        iterator prev = boost::begin(view);
+
+        iterator cur = std::find_if(prev, boost::end(view), not_equal(*prev));
+        if ( cur == boost::end(view) )
+        {
+            // the range has only one distinct point, so it
+            // cannot have a spike
+            return false;
+        }
+
+        iterator next = std::find_if(cur, boost::end(view), not_equal(*cur));
+        if ( next == boost::end(view) )
+        {
+            // the range has only two distinct points, so it
+            // cannot have a spike
+            return false;
+        }
+
+        while ( next != boost::end(view) )
+        {
+            if ( geometry::detail::point_is_spike_or_equal(*prev,
+                                                           *next,
+                                                           *cur) )
+            {
+                return true;
+            }
+            prev = cur;
+            cur = next;
+            next = std::find_if(cur, boost::end(view), not_equal(*cur));
+        }
+
+        if ( geometry::equals(range::front(view), range::back(view)) )
+        {
+            iterator cur = boost::begin(view);
+            typename boost::range_reverse_iterator
+                <
+                    view_type const
+                >::type prev = std::find_if(boost::rbegin(view),
+                                            boost::rend(view),
+                                            not_equal(range::back(view)));
+            iterator next =
+                std::find_if(cur, boost::end(view), not_equal(*cur));
+            return detail::point_is_spike_or_equal(*prev, *next, *cur);
+        }
+
+        return false;
+    }
+};
+
+
+
+}} // namespace detail::is_valid
+#endif // DOXYGEN_NO_DETAIL
+
+
+}} // namespace boost::geometry
+
+
+#endif // BOOST_GEOMETRY_ALGORITHMS_DETAIL_IS_VALID_HAS_SPIKES_HPP