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cpp-thirdparty/winx64/include/boost/geometry/algorithms/detail/overlay/traversal.hpp
Bassem Girgis 81b4b9e273 Initial commit
2018-12-20 17:34:07 -06:00

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// Boost.Geometry (aka GGL, Generic Geometry Library)
// Copyright (c) 2007-2012 Barend Gehrels, Amsterdam, the Netherlands.
// 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_ALGORITHMS_DETAIL_OVERLAY_TRAVERSAL_HPP
#define BOOST_GEOMETRY_ALGORITHMS_DETAIL_OVERLAY_TRAVERSAL_HPP
#include <cstddef>
#include <boost/range.hpp>
#include <boost/geometry/algorithms/detail/overlay/aggregate_operations.hpp>
#include <boost/geometry/algorithms/detail/overlay/sort_by_side.hpp>
#include <boost/geometry/algorithms/detail/overlay/turn_info.hpp>
#include <boost/geometry/core/access.hpp>
#include <boost/geometry/core/assert.hpp>
#if defined(BOOST_GEOMETRY_DEBUG_INTERSECTION) \
|| defined(BOOST_GEOMETRY_OVERLAY_REPORT_WKT) \
|| defined(BOOST_GEOMETRY_DEBUG_TRAVERSE)
# include <string>
# include <boost/geometry/algorithms/detail/overlay/debug_turn_info.hpp>
# include <boost/geometry/io/wkt/wkt.hpp>
#endif
namespace boost { namespace geometry
{
#ifndef DOXYGEN_NO_DETAIL
namespace detail { namespace overlay
{
template <typename Turn, typename Operation>
#ifdef BOOST_GEOMETRY_DEBUG_TRAVERSE
inline void debug_traverse(Turn const& turn, Operation op,
std::string const& header)
{
std::cout << header
<< " at " << op.seg_id
<< " meth: " << method_char(turn.method)
<< " op: " << operation_char(op.operation)
<< " vis: " << visited_char(op.visited)
<< " of: " << operation_char(turn.operations[0].operation)
<< operation_char(turn.operations[1].operation)
<< " " << geometry::wkt(turn.point)
<< std::endl;
if (boost::contains(header, "Finished"))
{
std::cout << std::endl;
}
}
#else
inline void debug_traverse(Turn const& , Operation, const char*)
{
}
#endif
//! Metafunction to define side_order (clockwise, ccw) by operation_type
template <operation_type OpType>
struct side_compare {};
template <>
struct side_compare<operation_union>
{
typedef std::greater<int> type;
};
template <>
struct side_compare<operation_intersection>
{
typedef std::less<int> type;
};
template
<
bool Reverse1,
bool Reverse2,
overlay_type OverlayType,
typename Geometry1,
typename Geometry2,
typename Turns,
typename Clusters,
typename RobustPolicy,
typename Visitor
>
struct traversal
{
static const operation_type target_operation = operation_from_overlay<OverlayType>::value;
typedef typename side_compare<target_operation>::type side_compare_type;
typedef typename boost::range_value<Turns>::type turn_type;
typedef typename turn_type::turn_operation_type turn_operation_type;
typedef typename geometry::point_type<Geometry1>::type point_type;
typedef sort_by_side::side_sorter
<
Reverse1, Reverse2,
point_type, side_compare_type
> sbs_type;
inline traversal(Geometry1 const& geometry1, Geometry2 const& geometry2,
Turns& turns, Clusters const& clusters,
RobustPolicy const& robust_policy, Visitor& visitor)
: m_geometry1(geometry1)
, m_geometry2(geometry2)
, m_turns(turns)
, m_clusters(clusters)
, m_robust_policy(robust_policy)
, m_visitor(visitor)
{
}
inline void finalize_visit_info()
{
for (typename boost::range_iterator<Turns>::type
it = boost::begin(m_turns);
it != boost::end(m_turns);
++it)
{
turn_type& turn = *it;
for (int i = 0; i < 2; i++)
{
turn_operation_type& op = turn.operations[i];
op.visited.finalize();
}
}
}
inline void set_visited(turn_type& turn, turn_operation_type& op)
{
// On "continue", set "visited" for ALL directions in this turn
if (op.operation == detail::overlay::operation_continue)
{
for (int i = 0; i < 2; i++)
{
turn_operation_type& turn_op = turn.operations[i];
if (turn_op.visited.none())
{
turn_op.visited.set_visited();
}
}
}
else
{
op.visited.set_visited();
}
}
inline bool is_visited(turn_type const& , turn_operation_type const& op,
signed_size_type , int) const
{
return op.visited.visited();
}
inline bool select_source(signed_size_type turn_index,
segment_identifier const& seg_id1,
segment_identifier const& seg_id2) const
{
// For uu/ii, only switch sources if indicated
turn_type const& turn = m_turns[turn_index];
if (OverlayType == overlay_buffer)
{
// Buffer does not use source_index (always 0)
return turn.switch_source
? seg_id1.multi_index != seg_id2.multi_index
: seg_id1.multi_index == seg_id2.multi_index;
}
#if defined(BOOST_GEOMETRY_DEBUG_TRAVERSAL_SWITCH_DETECTOR)
if (turn.switch_source)
{
std::cout << "Switch source at " << turn_index << std::endl;
}
else
{
std::cout << "DON'T SWITCH SOURCES at " << turn_index << std::endl;
}
#endif
return turn.switch_source
? seg_id1.source_index != seg_id2.source_index
: seg_id1.source_index == seg_id2.source_index;
}
inline
signed_size_type get_next_turn_index(turn_operation_type const& op) const
{
return op.enriched.next_ip_index == -1
? op.enriched.travels_to_ip_index
: op.enriched.next_ip_index;
}
inline bool traverse_possible(signed_size_type turn_index) const
{
if (turn_index == -1)
{
return false;
}
turn_type const& turn = m_turns[turn_index];
// It is not a dead end if there is an operation to continue, or of
// there is a cluster (assuming for now we can get out of the cluster)
return turn.cluster_id >= 0
|| turn.has(target_operation)
|| turn.has(operation_continue);
}
inline
bool select_cc_operation(turn_type const& turn,
signed_size_type start_turn_index,
int& selected_op_index) const
{
// For "cc", take either one, but if there is a starting one,
// take that one. If next is dead end, skip that one.
bool result = false;
typename turn_operation_type::comparable_distance_type
max_remaining_distance = 0;
for (int i = 0; i < 2; i++)
{
turn_operation_type const& op = turn.operations[i];
signed_size_type const next_turn_index = get_next_turn_index(op);
if (! result && traverse_possible(next_turn_index))
{
max_remaining_distance = op.remaining_distance;
selected_op_index = i;
debug_traverse(turn, op, " Candidate");
result = true;
}
if (result)
{
if (next_turn_index == start_turn_index)
{
selected_op_index = i;
debug_traverse(turn, op, " Candidate cc override (start)");
}
else if (op.remaining_distance > max_remaining_distance)
{
max_remaining_distance = op.remaining_distance;
selected_op_index = i;
debug_traverse(turn, op, " Candidate cc override (remaining)");
}
}
}
return result;
}
inline
bool select_noncc_operation(turn_type const& turn,
signed_size_type turn_index,
segment_identifier const& seg_id,
int& selected_op_index) const
{
bool result = false;
for (int i = 0; i < 2; i++)
{
turn_operation_type const& op = turn.operations[i];
if (op.operation == target_operation
&& ! op.visited.finished()
&& (! result || select_source(turn_index, op.seg_id, seg_id)))
{
selected_op_index = i;
debug_traverse(turn, op, " Candidate");
result = true;
}
}
return result;
}
inline
bool select_operation(const turn_type& turn,
signed_size_type turn_index,
signed_size_type start_turn_index,
segment_identifier const& previous_seg_id,
int& selected_op_index) const
{
bool result = false;
selected_op_index = -1;
if (turn.both(operation_continue))
{
result = select_cc_operation(turn, start_turn_index,
selected_op_index);
}
else
{
result = select_noncc_operation(turn, turn_index,
previous_seg_id, selected_op_index);
}
if (result)
{
debug_traverse(turn, turn.operations[selected_op_index], " Accepted");
}
return result;
}
inline int starting_operation_index(const turn_type& turn) const
{
for (int i = 0; i < 2; i++)
{
if (turn.operations[i].visited.started())
{
return i;
}
}
return -1;
}
inline bool both_finished(const turn_type& turn) const
{
for (int i = 0; i < 2; i++)
{
if (! turn.operations[i].visited.finished())
{
return false;
}
}
return true;
}
inline bool select_from_cluster_union(signed_size_type& turn_index,
int& op_index, signed_size_type start_turn_index,
sbs_type const& sbs, bool is_touching) const
{
std::size_t selected_rank = 0;
std::size_t min_rank = 0;
bool result = false;
for (std::size_t i = 0; i < sbs.m_ranked_points.size(); i++)
{
typename sbs_type::rp const& ranked_point = sbs.m_ranked_points[i];
if (result && ranked_point.rank > selected_rank)
{
return result;
}
turn_type const& ranked_turn = m_turns[ranked_point.turn_index];
turn_operation_type const& ranked_op = ranked_turn.operations[ranked_point.operation_index];
if (result && ranked_op.visited.finalized())
{
// One of the arcs in the same direction as the selected result
// is already traversed.
return false;
}
if (! is_touching && ranked_op.visited.finalized())
{
// Skip this one, go to next
min_rank = ranked_point.rank;
continue;
}
if (ranked_point.direction == sort_by_side::dir_to
&& (ranked_point.rank > min_rank
|| ranked_turn.both(operation_continue)))
{
if (ranked_op.enriched.count_left == 0
&& ranked_op.enriched.count_right > 0)
{
if (result && ranked_point.turn_index != start_turn_index)
{
// Don't override - only override if arrive at start
continue;
}
turn_index = ranked_point.turn_index;
op_index = ranked_point.operation_index;
result = true;
selected_rank = ranked_point.rank;
}
else if (! is_touching)
{
return result;
}
}
}
return result;
}
inline bool analyze_cluster_intersection(signed_size_type& turn_index,
int& op_index,
sbs_type const& sbs) const
{
std::vector<sort_by_side::rank_with_rings> aggregation;
sort_by_side::aggregate_operations(sbs, aggregation);
std::size_t selected_rank = 0;
for (std::size_t i = 0; i < aggregation.size(); i++)
{
sort_by_side::rank_with_rings const& rwr = aggregation[i];
if (i > 1
&& i - 1 == selected_rank
&& rwr.rings.size() == 1)
{
sort_by_side::ring_with_direction const& rwd = *rwr.rings.begin();
if (rwd.only_turn_on_ring)
{
// Find if this arriving ring was leaving previously
sort_by_side::ring_with_direction leaving = rwd;
leaving.direction = sort_by_side::dir_to;
sort_by_side::rank_with_rings const& previous = aggregation[i - 1];
if (previous.rings.size() == 1
&& previous.rings.count(leaving) == 1)
{
// It arrives back - if this is one of the selected, unselect it
selected_rank = 0;
}
}
}
if (rwr.all_to())
{
if (selected_rank == 0)
{
// Take the first (= right) where segments leave,
// having the polygon on the right side
selected_rank = rwr.rank;
}
}
}
if (selected_rank > 0)
{
std::size_t selected_index = sbs.m_ranked_points.size();
for (std::size_t i = 0; i < sbs.m_ranked_points.size(); i++)
{
typename sbs_type::rp const& ranked_point = sbs.m_ranked_points[i];
if (ranked_point.rank == selected_rank)
{
turn_type const& ranked_turn = m_turns[ranked_point.turn_index];
turn_operation_type const& ranked_op = ranked_turn.operations[ranked_point.operation_index];
if (ranked_op.visited.finalized())
{
// This direction is already traveled before, the same
// cannot be traveled again
return false;
}
// Take the last turn from this rank
selected_index = i;
}
}
if (selected_index < sbs.m_ranked_points.size())
{
typename sbs_type::rp const& ranked_point = sbs.m_ranked_points[selected_index];
turn_index = ranked_point.turn_index;
op_index = ranked_point.operation_index;
return true;
}
}
return false;
}
inline bool select_turn_from_cluster(signed_size_type& turn_index,
int& op_index, bool& is_touching,
signed_size_type start_turn_index,
segment_identifier const& previous_seg_id,
bool is_start) const
{
bool const is_union = target_operation == operation_union;
turn_type const& turn = m_turns[turn_index];
BOOST_ASSERT(turn.cluster_id >= 0);
typename Clusters::const_iterator mit = m_clusters.find(turn.cluster_id);
BOOST_ASSERT(mit != m_clusters.end());
cluster_info const& cinfo = mit->second;
std::set<signed_size_type> const& ids = cinfo.turn_indices;
sbs_type sbs;
bool has_origin = false;
for (typename std::set<signed_size_type>::const_iterator sit = ids.begin();
sit != ids.end(); ++sit)
{
signed_size_type cluster_turn_index = *sit;
turn_type const& cluster_turn = m_turns[cluster_turn_index];
if (cluster_turn.discarded)
{
// Defensive check, discarded turns should not be in cluster
continue;
}
for (int i = 0; i < 2; i++)
{
turn_operation_type const& op = cluster_turn.operations[i];
bool is_origin = false;
if (cluster_turn_index == turn_index)
{
// Check if this is the origin
if (OverlayType == overlay_buffer)
{
is_origin = op.seg_id.multi_index == previous_seg_id.multi_index;
}
else
{
is_origin = op.seg_id.source_index
== previous_seg_id.source_index;
}
if (is_origin)
{
has_origin = true;
}
}
sbs.add(op, cluster_turn_index, i, m_geometry1, m_geometry2,
is_origin);
}
}
if (! has_origin)
{
return false;
}
sbs.apply(turn.point);
bool result = false;
if (is_union)
{
#if defined(BOOST_GEOMETRY_DEBUG_TRAVERSAL_SWITCH_DETECTOR)
is_touching = cinfo.open_count > 1;
if (is_touching)
{
if (cinfo.switch_source)
{
is_touching = false;
std::cout << "CLUSTER: SWITCH SOURCES at " << turn_index << std::endl;
}
else
{
std::cout << "CLUSTER: CONTINUE at " << turn_index << std::endl;
}
}
#else
is_touching = cinfo.open_count > 1 && ! cinfo.switch_source;
#endif
if (is_touching)
{
sbs.reverse();
}
result = select_from_cluster_union(turn_index, op_index, start_turn_index, sbs,
is_touching);
}
else
{
if (is_start
&& turn.both(operation_intersection)
&& turn.operations[op_index].enriched.only_turn_on_ring)
{
// For an ii (usually interior ring), only turn on ring,
// reverse to take first exit
sbs.reverse();
}
result = analyze_cluster_intersection(turn_index, op_index, sbs);
}
return result;
}
inline bool analyze_ii_intersection(signed_size_type& turn_index, int& op_index,
turn_type const& current_turn,
segment_identifier const& previous_seg_id)
{
sbs_type sbs;
// Add this turn to the sort-by-side sorter
bool has_origin = false;
for (int i = 0; i < 2; i++)
{
turn_operation_type const& op = current_turn.operations[i];
bool const is_origin = op.seg_id.source_index
== previous_seg_id.source_index;
has_origin = has_origin || is_origin;
sbs.add(op, turn_index, i, m_geometry1, m_geometry2, is_origin);
}
if (! has_origin)
{
return false;
}
sbs.apply(current_turn.point);
return analyze_cluster_intersection(turn_index, op_index, sbs);
}
inline void change_index_for_self_turn(signed_size_type& to_vertex_index,
turn_type const& start_turn,
turn_operation_type const& start_op,
int start_op_index) const
{
if (OverlayType != overlay_buffer)
{
return;
}
// It travels to itself, can happen. If this is a buffer, it can
// sometimes travel to itself in the following configuration:
//
// +---->--+
// | |
// | +---*----+ *: one turn, with segment index 2/7
// | | | |
// | +---C | C: closing point (start/end)
// | |
// +------------+
//
// If it starts on segment 2 and travels to itself on segment 2, that
// should be corrected to 7 because that is the shortest path
//
// Also a uu turn (touching with another buffered ring) might have this
// apparent configuration, but there it should
// always travel the whole ring
turn_operation_type const& other_op
= start_turn.operations[1 - start_op_index];
bool const correct
= ! start_turn.both(operation_union)
&& start_op.seg_id.segment_index == to_vertex_index;
#if defined(BOOST_GEOMETRY_DEBUG_TRAVERSE)
std::cout << " WARNING: self-buffer "
<< " correct=" << correct
<< " turn=" << operation_char(start_turn.operations[0].operation)
<< operation_char(start_turn.operations[1].operation)
<< " start=" << start_op.seg_id.segment_index
<< " from=" << to_vertex_index
<< " to=" << other_op.enriched.travels_to_vertex_index
<< std::endl;
#endif
if (correct)
{
to_vertex_index = other_op.enriched.travels_to_vertex_index;
}
}
bool select_turn_from_enriched(signed_size_type& turn_index,
segment_identifier& previous_seg_id,
signed_size_type& to_vertex_index,
signed_size_type start_turn_index,
int start_op_index,
turn_type const& previous_turn,
turn_operation_type const& previous_op,
bool is_start) const
{
to_vertex_index = -1;
if (previous_op.enriched.next_ip_index < 0)
{
// There is no next IP on this segment
if (previous_op.enriched.travels_to_vertex_index < 0
|| previous_op.enriched.travels_to_ip_index < 0)
{
return false;
}
to_vertex_index = previous_op.enriched.travels_to_vertex_index;
if (is_start &&
previous_op.enriched.travels_to_ip_index == start_turn_index)
{
change_index_for_self_turn(to_vertex_index, previous_turn,
previous_op, start_op_index);
}
turn_index = previous_op.enriched.travels_to_ip_index;
previous_seg_id = previous_op.seg_id;
}
else
{
// Take the next IP on this segment
turn_index = previous_op.enriched.next_ip_index;
previous_seg_id = previous_op.seg_id;
}
return true;
}
bool select_turn(signed_size_type start_turn_index, int start_op_index,
signed_size_type& turn_index,
int& op_index,
bool& is_touching,
int previous_op_index,
signed_size_type previous_turn_index,
segment_identifier const& previous_seg_id,
bool is_start)
{
turn_type const& current_turn = m_turns[turn_index];
if (target_operation == operation_intersection)
{
bool const back_at_start_cluster
= current_turn.cluster_id >= 0
&& m_turns[start_turn_index].cluster_id == current_turn.cluster_id;
if (turn_index == start_turn_index || back_at_start_cluster)
{
// Intersection can always be finished if returning
turn_index = start_turn_index;
op_index = start_op_index;
return true;
}
if (current_turn.cluster_id < 0
&& current_turn.both(operation_intersection))
{
if (analyze_ii_intersection(turn_index, op_index, current_turn,
previous_seg_id))
{
return true;
}
}
}
if (current_turn.cluster_id >= 0)
{
if (! select_turn_from_cluster(turn_index, op_index, is_touching,
start_turn_index, previous_seg_id, is_start))
{
return false;
}
if (is_start && turn_index == previous_turn_index)
{
op_index = previous_op_index;
}
}
else
{
op_index = starting_operation_index(current_turn);
if (op_index == -1)
{
if (both_finished(current_turn))
{
return false;
}
if (! select_operation(current_turn, turn_index,
start_turn_index,
previous_seg_id,
op_index))
{
return false;
}
}
}
return true;
}
private :
Geometry1 const& m_geometry1;
Geometry2 const& m_geometry2;
Turns& m_turns;
Clusters const& m_clusters;
RobustPolicy const& m_robust_policy;
Visitor& m_visitor;
};
}} // namespace detail::overlay
#endif // DOXYGEN_NO_DETAIL
}} // namespace boost::geometry
#endif // BOOST_GEOMETRY_ALGORITHMS_DETAIL_OVERLAY_TRAVERSAL_HPP