cgal/Orthtree/include/CGAL/Orthtree/Split_predicates.h

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// Copyright (c) 2007-2020 INRIA (France).
// All rights reserved.
//
// This file is part of CGAL (www.cgal.org).
//
// $URL$
// $Id$
// SPDX-License-Identifier: GPL-3.0-or-later OR LicenseRef-Commercial
//
// Author(s) : Jackson Campolattaro, Cédric Portaneri, Tong Zhao
#ifndef CGAL_ORTHTREE_SPLIT_PREDICATES_H
#define CGAL_ORTHTREE_SPLIT_PREDICATES_H
#include <CGAL/license/Orthtree.h>
#include <iostream>
namespace CGAL {
template <typename GeomTraits>
class Orthtree;
namespace Orthtrees {
/*!
\ingroup PkgOrthtreeSplitPredicates
\brief A class used to choose when a node should be split depending on the number of contained elements.
This is a bucket size predicate that considers a node should be
split if it contains more than a certain number of items.
\warning This split predicate is only appropriate for trees with traits classes which are models of `OrthtreeTraitsWithData`
and where `Node_data` is a model of `Range`. `RandomAccessRange` is suggested for performance.
*/
class Maximum_contained_elements {
std::size_t m_bucket_size;
public:
/*!
\brief creates a predicate based on the number of contained elements.
*/
Maximum_contained_elements(std::size_t bucket_size) :
m_bucket_size(bucket_size) {}
/*!
\brief returns `true` if the node with index `i` should be split, `false` otherwise.
*/
template<typename GeomTraits>
bool operator()(typename Orthtree<GeomTraits>::Node_index i, const Orthtree<GeomTraits> &tree) const {
return (tree.data(i).size() > m_bucket_size);
}
};
/*!
\ingroup PkgOrthtreeSplitPredicates
\brief A class used to choose when a node should be split depending on the depth.
This predicate makes a node be split if its depth is lower than a certain limit.
*/
class Maximum_depth {
std::size_t m_max_depth;
public:
/*!
\brief creates a maximum depth predicate.
*/
Maximum_depth(std::size_t max_depth) : m_max_depth(max_depth) {}
/*!
\brief returns `true` if the node with index `i` should be split, `false` otherwise.
*/
template<typename GeomTraits>
bool operator()(typename Orthtree<GeomTraits>::Node_index i, const Orthtree<GeomTraits> &tree) const {
return (tree.depth(i) < m_max_depth);
}
};
/*!
\ingroup PkgOrthtreeSplitPredicates
\brief A class used to choose when a node should be split depending on the depth and the number of contained elements.
This predicate makes a node split if it contains more than a
certain number of items and if its depth is lower than a certain
limit.
The refinement is stopped as soon as one of the conditions is
violated: if a node has more elements than `bucket_size` but is
already at `max_depth`, it is not split. Similarly, a node that is
at a depth smaller than `max_depth` but already has fewer elements
than `bucket_size`, it is not split.
\warning This split predicate is only appropriate for trees with traits classes which are models of `OrthtreeTraitsWithData`
and where `Node_data` is a model of `Range`. `RandomAccessRange` is suggested for performance.
*/
class Maximum_depth_and_maximum_contained_elements {
std::size_t m_max_depth, m_bucket_size;
public:
/*! \brief creates a predicate using maximum depth or bucket size.
*/
Maximum_depth_and_maximum_contained_elements(std::size_t max_depth, std::size_t bucket_size) :
m_max_depth(max_depth), m_bucket_size(bucket_size) {}
/*!
\brief returns `true` if the node with index `i` should be split, `false` otherwise.
*/
template<typename GeomTraits>
bool operator()(typename Orthtree<GeomTraits>::Node_index i, const Orthtree<GeomTraits> &tree) const {
std::size_t num_points = tree.data(i).size();
std::size_t depth = tree.depth(i);
return (num_points > m_bucket_size && depth < m_max_depth);
}
};
} // Orthtrees
} // CGAL
#endif //CGAL_ORTHTREE_SPLIT_PREDICATES_H