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Subject: [Boost-commit] svn:boost r84720 - in trunk/boost/geometry/index: . detail detail/rtree
From: adam.wulkiewicz_at_[hidden]
Date: 2013-06-09 23:43:10


Author: awulkiew
Date: 2013-06-09 23:43:10 EDT (Sun, 09 Jun 2013)
New Revision: 84720
URL: http://svn.boost.org/trac/boost/changeset/84720

Log:
geometry.index: added experimental packing algorithm, some varray warnings fixed.

Added:
   trunk/boost/geometry/index/detail/rtree/pack_create.hpp (contents, props changed)
Text files modified:
   trunk/boost/geometry/index/detail/rtree/pack_create.hpp | 328 ++++++++++++++++++++++++++++++++++++++++
   trunk/boost/geometry/index/detail/varray.hpp | 7
   trunk/boost/geometry/index/rtree.hpp | 19 ++
   3 files changed, 353 insertions(+), 1 deletions(-)

Added: trunk/boost/geometry/index/detail/rtree/pack_create.hpp
==============================================================================
--- /dev/null 00:00:00 1970 (empty, because file is newly added)
+++ trunk/boost/geometry/index/detail/rtree/pack_create.hpp 2013-06-09 23:43:10 EDT (Sun, 09 Jun 2013) (r84720)
@@ -0,0 +1,328 @@
+// Boost.Geometry Index
+//
+// R-tree initial packing
+//
+// Copyright (c) 2011-2013 Adam Wulkiewicz, Lodz, Poland.
+//
+// Use, modification and distribution is subject to the Boost Software License,
+// Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
+// http://www.boost.org/LICENSE_1_0.txt)
+
+#ifndef BOOST_GEOMETRY_INDEX_DETAIL_RTREE_PACK_CREATE_HPP
+#define BOOST_GEOMETRY_INDEX_DETAIL_RTREE_PACK_CREATE_HPP
+
+namespace boost { namespace geometry { namespace index { namespace detail { namespace rtree {
+
+// STR leafs number are calculated as rcount/max
+// and the number of splitting planes for each dimension as (count/max)^(1/dimension)
+// <-> for dimension==2 -> sqrt(count/max)
+//
+// The main flaw of this algorithm is that the resulting tree will have bad structure for:
+// 1. non-uniformly distributed elements
+// Statistic check could be performed, e.g. based on variance of lengths of elements edges for each dimension
+// 2. elements distributed mainly along one axis
+// Calculate bounding box of all elements and then number of dividing planes for a dimension
+// from the length of BB edge for this dimension (more or less assuming that elements are uniformly-distributed squares)
+//
+// Another thing is that the last node may have less elements than Max or even Min.
+// The number of splitting planes must be chosen more carefully than count/max
+//
+// This algorithm is something between STR and TGS
+// it is more similar to the top-down recursive kd-tree creation algorithm
+// using object median split and split axis of greatest BB edge
+// BB is only used as a hint (assuming objects are distributed uniformly)
+
+template <typename Value, typename Options, typename Translator, typename Box, typename Allocators>
+class packer
+{
+ typedef typename rtree::node<Value, typename Options::parameters_type, Box, Allocators, typename Options::node_tag>::type node;
+ typedef typename rtree::internal_node<Value, typename Options::parameters_type, Box, Allocators, typename Options::node_tag>::type internal_node;
+ typedef typename rtree::leaf<Value, typename Options::parameters_type, Box, Allocators, typename Options::node_tag>::type leaf;
+
+ typedef typename Allocators::node_pointer node_pointer;
+
+ typedef typename traits::point_type<Box>::type point_type;
+ typedef typename traits::coordinate_type<point_type>::type coordinate_type;
+ typedef typename detail::default_content_result<Box>::type content_type;
+ typedef typename Options::parameters_type parameters_type;
+ static const std::size_t dimension = traits::dimension<point_type>::value;
+
+ typedef typename rtree::container_from_elements_type<
+ typename rtree::elements_type<leaf>::type,
+ std::size_t
+ >::type values_counts_container;
+
+ typedef typename rtree::elements_type<internal_node>::type internal_elements;
+ typedef typename internal_elements::value_type internal_element;
+
+public:
+ packer(parameters_type const& p, Translator const& tr, Allocators & al) : m_parameters(p), m_translator(tr), m_allocators(al) {}
+
+ // Arbitrary iterators
+ template <typename InIt>
+ node_pointer pack(InIt first, InIt last)
+ {
+ typedef std::pair<point_type, InIt> entry_type;
+ std::vector<entry_type> entries;
+
+ // TODO if RandomAccess
+ // count = distance(first, last);
+ // reserve(count);
+
+ Box hint_box;
+ geometry::assign_inverse(hint_box);
+
+ std::size_t count = 0;
+ for ( ; first != last ; ++first, ++count )
+ {
+ geometry::expand(hint_box, m_translator(*first));
+
+ point_type pt;
+ geometry::centroid(m_translator(*first), pt);
+ entries.push_back(std::make_pair(pt, first));
+ }
+
+ std::pair<std::size_t, std::size_t> subtree_counts = subtree_elements_counts(count);
+ internal_element el = per_level(entries.begin(), entries.end(), hint_box, count, subtree_counts);
+ return el.second;
+ }
+
+private:
+ template <typename EIt>
+ internal_element per_level(EIt first, EIt last, Box const& hint_box, std::size_t count, std::pair<std::size_t, std::size_t> const& subtree_counts)
+ {
+ // remove it later
+ BOOST_ASSERT(first <= last); BOOST_ASSERT(last - first == count);
+
+ if ( subtree_counts.first <= 1 )
+ {
+ // ROOT or LEAF
+ BOOST_ASSERT(count <= m_parameters.get_max_elements());
+ // if !root check m_parameters.get_min_elements() <= count
+
+ // create new leaf node
+ node_pointer n = rtree::create_node<Allocators, leaf>::apply(m_allocators); // MAY THROW (A)
+ leaf & l = rtree::get<leaf>(*n);
+ // reserve space for values
+ rtree::elements(l).reserve(count); // MAY THROW (A)
+ // calculate values box and copy values
+ Box elements_box;
+ geometry::assign_inverse(elements_box);
+ for ( ; first != last ; ++first )
+ {
+ rtree::elements(l).push_back(*(first->second)); // MAY THROW (C)
+ geometry::expand(elements_box, m_translator(*(first->second)));
+ }
+ return internal_element(elements_box, n);
+ }
+
+ // calculate numbers of values in subtrees
+ values_counts_container values_counts;
+ calculate_nodes_counts(values_counts, count, subtree_counts); // MAY THROW (A)
+ BOOST_ASSERT(are_nodes_counts_ok(values_counts, count, subtree_counts));
+
+ // calculate next max and min subtree counts
+ std::pair<std::size_t, std::size_t> next_subtree_counts = subtree_counts;
+ next_subtree_counts.first /= m_parameters.get_max_elements();
+ next_subtree_counts.second /= m_parameters.get_max_elements();
+
+ // create new internal node
+ node_pointer n = rtree::create_node<Allocators, internal_node>::apply(m_allocators); // MAY THROW (A)
+ internal_node & in = rtree::get<internal_node>(*n);
+ // reserve space for values
+ rtree::elements(in).reserve(values_counts.size()); // MAY THROW (A)
+ // calculate values box and copy values
+ Box elements_box;
+ geometry::assign_inverse(elements_box);
+
+ per_level_packets(first, last, values_counts.begin(), values_counts.end(),
+ hint_box, next_subtree_counts,
+ rtree::elements(in), elements_box);
+
+ return internal_element(elements_box, n);
+ }
+
+ template <typename EIt, typename CIt>
+ void per_level_packets(EIt first, EIt last, CIt counts_first, CIt counts_last,
+ Box const& hint_box,
+ std::pair<std::size_t, std::size_t> const& next_subtree_counts,
+ internal_elements & elements, Box & elements_box)
+ {
+ std::size_t packets_count = counts_last - counts_first;
+
+ BOOST_ASSERT( 0 < packets_count );
+
+ if ( 1 == packets_count )
+ {
+ // the end, move to the next level
+ internal_element el = per_level(first, last, hint_box, *counts_first, next_subtree_counts);
+ elements.push_back(el); // SHOULDN'T THROW (C)
+ geometry::expand(elements_box, el.first);
+ return;
+ }
+
+ CIt counts_median = counts_first + packets_count / 2;
+ std::size_t left_sum = 0;
+ for ( CIt it = counts_first ; it != counts_median ; ++it )
+ left_sum += *it;
+
+ EIt median = first + left_sum;
+
+ coordinate_type greatest_length;
+ std::size_t greatest_dim_index = 0;
+ biggest_edge<dimension>::apply(hint_box, greatest_length, greatest_dim_index);
+ partial_sort_for_dimension<0, dimension>::apply(first, median, last, greatest_dim_index);
+ Box left, right;
+ half_boxes_for_dimension<0, dimension>::apply(hint_box, left, right, greatest_dim_index);
+
+ per_level_packets(first, median, counts_first, counts_median, left, next_subtree_counts, elements, elements_box);
+ per_level_packets(median, last, counts_median, counts_last, right, next_subtree_counts, elements, elements_box);
+ }
+
+ std::pair<std::size_t, std::size_t> subtree_elements_counts(std::size_t elements_count)
+ {
+ std::pair<std::size_t, std::size_t> res = std::make_pair(1, 1);
+
+ std::size_t smax = m_parameters.get_max_elements();
+ std::size_t smin = m_parameters.get_min_elements();
+
+ for ( ; smax < elements_count ; smax *= m_parameters.get_max_elements(), smin *= m_parameters.get_max_elements() )
+ {
+ res.first = smax;
+ res.second = smin;
+ }
+
+ return res;
+ }
+
+ void calculate_nodes_counts(values_counts_container & values_counts,
+ std::size_t count,
+ std::pair<std::size_t, std::size_t> const& subtree_counts)
+ {
+ // e.g. for max = 5, min = 2, count = 52, subtree_max = 25, subtree_min = 10
+
+ std::size_t n = count / subtree_counts.first; // e.g. 52 / 25 = 2
+ std::size_t r = count % subtree_counts.first; // e.g. 52 % 25 = 2
+ bool is_min_node = false;
+
+ if ( 0 < r && r < subtree_counts.second ) // 2 < 10
+ {
+ is_min_node = true;
+ std::size_t count_minus_min = count - subtree_counts.second; // e.g. 52 - 10 = 42
+ n = count_minus_min / subtree_counts.first; // e.g. 42 / 25 = 1
+ r = count_minus_min % subtree_counts.first; // e.g. 42 % 25 = 17
+ }
+
+ values_counts.resize(n, subtree_counts.first); // MAY THROW (A)
+ if ( 0 < r )
+ values_counts.push_back(r); // MAY THROW (A)
+ if ( is_min_node )
+ values_counts.push_back(subtree_counts.second); // MAY THROW (A)
+ }
+
+ bool are_nodes_counts_ok(values_counts_container const& values_counts,
+ std::size_t count,
+ std::pair<std::size_t, std::size_t> const& subtree_counts)
+ {
+ std::size_t sum = 0;
+
+ for(std::size_t i = 0 ; i < values_counts.size() ; ++i )
+ {
+ std::size_t c = values_counts[i];
+ sum += c;
+ if ( c < subtree_counts.second || subtree_counts.first < c )
+ return false;
+ }
+ if ( sum != count )
+ return false;
+ return true;
+ }
+
+ template <std::size_t Dimension>
+ struct biggest_edge
+ {
+ BOOST_STATIC_ASSERT(0 < Dimension);
+ static inline void apply(Box const& box, coordinate_type & length, std::size_t & dim_index)
+ {
+ biggest_edge<Dimension-1>::apply(box, length, dim_index);
+ coordinate_type curr = geometry::get<max_corner, Dimension-1>(box) - geometry::get<min_corner, Dimension-1>(box);
+ if ( length < curr )
+ {
+ dim_index = Dimension - 1;
+ length = curr;
+ }
+ }
+ };
+
+ template <>
+ struct biggest_edge<1>
+ {
+ static inline void apply(Box const& box, coordinate_type & length, std::size_t & dim_index)
+ {
+ dim_index = 0;
+ length = geometry::get<max_corner, 0>(box) - geometry::get<min_corner, 0>(box);
+ }
+ };
+
+ template <std::size_t I, std::size_t Dimension>
+ struct partial_sort_for_dimension
+ {
+ template <typename EIt>
+ static inline void apply(EIt first, EIt median, EIt last, std::size_t dim_index)
+ {
+ if ( I == dim_index )
+ std::partial_sort(first, median, last, point_entries_comparer<I>());
+ else
+ partial_sort_for_dimension<I+1, dimension>::apply(first, median, last, dim_index);
+ }
+ };
+
+ template <std::size_t Dimension>
+ struct partial_sort_for_dimension<Dimension, Dimension>
+ {
+ template <typename EIt>
+ static inline void apply(EIt , EIt , EIt , std::size_t ) {}
+ };
+
+ template <std::size_t I>
+ struct point_entries_comparer
+ {
+ template <typename typename PointEntry>
+ bool operator()(PointEntry const& e1, PointEntry const& e2) const
+ {
+ return geometry::get<I>(e1.first) < geometry::get<I>(e2.first);
+ }
+ };
+
+ template <std::size_t I, std::size_t Dimension>
+ struct half_boxes_for_dimension
+ {
+ static inline void apply(Box const& box, Box & left, Box & right, std::size_t dim_index)
+ {
+ if ( I == dim_index )
+ {
+ geometry::convert(box, left);
+ geometry::convert(box, right);
+ coordinate_type median = geometry::get<min_corner, I>(box) + (geometry::get<max_corner, I>(box) - geometry::get<min_corner, I>(box)) / 2;
+ geometry::set<max_corner, I>(left, median);
+ geometry::set<min_corner, I>(right, median);
+ }
+ else
+ half_boxes_for_dimension<I+1, dimension>::apply(box, left, right, dim_index);
+ }
+ };
+
+ template <std::size_t Dimension>
+ struct half_boxes_for_dimension<Dimension, Dimension>
+ {
+ static inline void apply(Box const& , Box & , Box & , std::size_t ) {}
+ };
+
+ parameters_type const& m_parameters;
+ Translator const& m_translator;
+ Allocators & m_allocators;
+};
+
+}}}}} // namespace boost::geometry::index::detail::rtree
+
+#endif // BOOST_GEOMETRY_INDEX_DETAIL_RTREE_PACK_CREATE_HPP

Modified: trunk/boost/geometry/index/detail/varray.hpp
==============================================================================
--- trunk/boost/geometry/index/detail/varray.hpp Sun Jun 9 17:41:00 2013 (r84719)
+++ trunk/boost/geometry/index/detail/varray.hpp 2013-06-09 23:43:10 EDT (Sun, 09 Jun 2013) (r84720)
@@ -70,7 +70,7 @@
     {
         BOOST_GEOMETRY_INDEX_ASSERT(s <= v.capacity(), "size too big");
         // unused params
- (void)v;
+ (void)v; (void)s;
     }
 
     static inline void throw_out_of_bounds(Varray const& v, size_type i)
@@ -81,26 +81,31 @@
 //#else // BOOST_NO_EXCEPTIONS
 // BOOST_GEOMETRY_INDEX_ASSERT(i < v.size(), "index out of bounds");
 //#endif // BOOST_NO_EXCEPTIONS
+ (void)v; (void)i;
     }
 
     static inline void check_index(Varray const& v, size_type i)
     {
         BOOST_GEOMETRY_INDEX_ASSERT(i < v.size(), "index out of bounds");
+ (void)v; (void)i;
     }
 
     static inline void check_not_empty(Varray const& v)
     {
         BOOST_GEOMETRY_INDEX_ASSERT(!v.empty(), "the container is empty");
+ (void)v;
     }
 
     static inline void check_iterator_end_neq(Varray const& v, const_iterator position)
     {
         BOOST_GEOMETRY_INDEX_ASSERT(v.begin() <= position && position < v.end(), "iterator out of bounds");
+ (void)v; (void)position;
     }
 
     static inline void check_iterator_end_eq(Varray const& v, const_iterator position)
     {
         BOOST_GEOMETRY_INDEX_ASSERT(v.begin() <= position && position <= v.end(), "iterator out of bounds");
+ (void)v; (void)position;
     }
 };
 

Modified: trunk/boost/geometry/index/rtree.hpp
==============================================================================
--- trunk/boost/geometry/index/rtree.hpp Sun Jun 9 17:41:00 2013 (r84719)
+++ trunk/boost/geometry/index/rtree.hpp 2013-06-09 23:43:10 EDT (Sun, 09 Jun 2013) (r84720)
@@ -56,6 +56,10 @@
 #include <boost/geometry/index/detail/rtree/rstar/rstar.hpp>
 //#include <boost/geometry/extensions/index/detail/rtree/kmeans/kmeans.hpp>
 
+#ifdef BOOST_GEOMETRY_INDEX_DETAIL_EXPERIMENTAL
+#include <boost/geometry/index/detail/rtree/pack_create.hpp>
+#endif
+
 #include <boost/geometry/index/inserter.hpp>
 
 #include <boost/geometry/index/detail/rtree/utilities/view.hpp>
@@ -235,6 +239,13 @@
                  allocator_type const& allocator = allocator_type())
         : m_members(getter, equal, parameters, allocator)
     {
+#ifdef BOOST_GEOMETRY_INDEX_DETAIL_EXPERIMENTAL
+ typedef detail::rtree::packer<value_type, options_type, translator_type, box_type, allocators_type> packer;
+
+ packer p(m_members.parameters(), m_members.translator(), m_members.allocators());
+ m_members.root = p.pack(first, last);
+#else
+
         BOOST_TRY
         {
             this->insert(first, last);
@@ -245,6 +256,7 @@
             BOOST_RETHROW
         }
         BOOST_CATCH_END
+#endif
     }
 
     /*!
@@ -269,6 +281,12 @@
                           allocator_type const& allocator = allocator_type())
         : m_members(getter, equal, parameters, allocator)
     {
+#ifdef BOOST_GEOMETRY_INDEX_DETAIL_EXPERIMENTAL
+ typedef detail::rtree::packer<value_type, options_type, translator_type, box_type, allocators_type> packer;
+
+ packer p(m_members.parameters(), m_members.translator(), m_members.allocators());
+ m_members.root = p.pack(::boost::begin(rng), ::boost::end(rng));
+#else
         BOOST_TRY
         {
             this->insert(rng);
@@ -279,6 +297,7 @@
             BOOST_RETHROW
         }
         BOOST_CATCH_END
+#endif
     }
 
     /*!


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