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nanomap/monav/contractionhierarchies/contractor.h

660 lines
21 KiB
C++

/*
Copyright 2010 Christian Vetter veaac.fdirct@gmail.com
This file is part of MoNav.
MoNav is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
MoNav is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with MoNav. If not, see <http://www.gnu.org/licenses/>.
*/
#ifndef CONTRACTOR_H_INCLUDED
#define CONTRACTOR_H_INCLUDED
#include <vector>
#include <omp.h>
#include <limits>
#include "utils/qthelpers.h"
#include "dynamicgraph.h"
#include "binaryheap.h"
#include "utils/config.h"
class Contractor {
public:
struct Witness {
NodeID source;
NodeID target;
NodeID middle;
};
private:
struct _EdgeData {
unsigned distance;
unsigned originalEdges : 29;
bool shortcut : 1;
bool forward : 1;
bool backward : 1;
union {
NodeID middle; // shortcut
unsigned id; // original edge
};
} data;
struct _HeapData {
};
typedef DynamicGraph< _EdgeData > _DynamicGraph;
typedef BinaryHeap< NodeID, NodeID, unsigned, _HeapData > _Heap;
typedef _DynamicGraph::InputEdge _ImportEdge;
struct _ThreadData {
_Heap heap;
std::vector< _ImportEdge > insertedEdges;
std::vector< Witness > witnessList;
std::vector< NodeID > neighbours;
_ThreadData( NodeID nodes ): heap( nodes ) {
}
};
struct _PriorityData {
int depth;
NodeID bias;
_PriorityData() {
depth = 0;
}
};
struct _ContractionInformation {
int edgesDeleted;
int edgesAdded;
int originalEdgesDeleted;
int originalEdgesAdded;
_ContractionInformation() {
edgesAdded = edgesDeleted = originalEdgesAdded = originalEdgesDeleted = 0;
}
};
struct _NodePartitionor {
bool operator()( std::pair< NodeID, bool > nodeData ) {
return !nodeData.second;
}
};
struct _LogItem {
unsigned iteration;
NodeID nodes;
double contraction;
double independent;
double inserting;
double removing;
double updating;
_LogItem() {
iteration = nodes = contraction = independent = inserting = removing = updating = 0;
}
double GetTotalTime() const {
return contraction + independent + inserting + removing + updating;
}
void PrintStatistics() const {
qDebug( "%d\t%d\t%lf\t%lf\t%lf\t%lf\t%lf", iteration, nodes, independent, contraction, inserting, removing, updating );
}
};
class _LogData {
public:
std::vector < _LogItem > iterations;
unsigned GetNIterations() {
return ( unsigned ) iterations.size();
}
_LogItem GetSum() const {
_LogItem sum;
sum.iteration = ( unsigned ) iterations.size();
for ( int i = 0, e = ( int ) iterations.size(); i < e; ++i ) {
sum.nodes += iterations[i].nodes;
sum.contraction += iterations[i].contraction;
sum.independent += iterations[i].independent;
sum.inserting += iterations[i].inserting;
sum.removing += iterations[i].removing;
sum.updating += iterations[i].updating;
}
return sum;
}
void PrintHeader() const {
qDebug( "Iteration\tNodes\tIndependent\tContraction\tInserting\tRemoving\tUpdating" );
}
void PrintSummary() const {
PrintHeader();
GetSum().PrintStatistics();
}
void Print() const {
PrintHeader();
for ( int i = 0, e = ( int ) iterations.size(); i < e; ++i )
iterations[i].PrintStatistics();
}
void Insert( const _LogItem& data ) {
iterations.push_back( data );
}
};
public:
template< class InputEdge >
Contractor( int nodes, const std::vector< InputEdge >& inputEdges ) {
std::vector< _ImportEdge > edges;
edges.reserve( 2 * inputEdges.size() );
int skippedLargeEdges = 0;
for ( typename std::vector< InputEdge >::const_iterator i = inputEdges.begin(), e = inputEdges.end(); i != e; ++i ) {
_ImportEdge edge;
edge.source = i->source;
edge.target = i->target;
edge.data.distance = std::max( i->distance * 10.0 + 0.5, 1.0 );
if ( edge.data.distance > 24 * 60 * 60 * 10 ) {
skippedLargeEdges++;
continue;
}
edge.data.shortcut = false;
edge.data.id = i - inputEdges.begin();
edge.data.forward = true;
edge.data.backward = i->bidirectional;
edge.data.originalEdges = 1;
if ( edge.data.distance < 1 ) {
qDebug() << edge.source << edge.target << edge.data.forward << edge.data.backward << edge.data.distance << edge.data.id << i->distance;
}
if ( edge.source == edge.target ) {
_loops.push_back( edge );
continue;
}
edges.push_back( edge );
std::swap( edge.source, edge.target );
edge.data.forward = i->bidirectional;
edge.data.backward = true;
edges.push_back( edge );
}
if ( skippedLargeEdges != 0 )
qDebug( "Skipped %d edges with too large edge weight", skippedLargeEdges );
std::sort( edges.begin(), edges.end() );
_graph = new _DynamicGraph( nodes, edges );
std::vector< _ImportEdge >().swap( edges );
}
~Contractor() {
delete _graph;
}
void Run() {
const NodeID numberOfNodes = _graph->GetNumberOfNodes();
_LogData log;
int maxThreads = omp_get_max_threads();
std::vector < _ThreadData* > threadData;
for ( int threadNum = 0; threadNum < maxThreads; ++threadNum ) {
threadData.push_back( new _ThreadData( numberOfNodes ) );
}
qDebug( "%d nodes, %d edges", numberOfNodes, _graph->GetNumberOfEdges() );
qDebug( "using %d threads", maxThreads );
NodeID levelID = 0;
NodeID iteration = 0;
std::vector< std::pair< NodeID, bool > > remainingNodes( numberOfNodes );
std::vector< double > nodePriority( numberOfNodes );
std::vector< _PriorityData > nodeData( numberOfNodes );
//initialize the variables
#pragma omp parallel for schedule ( guided )
for ( int x = 0; x < ( int ) numberOfNodes; ++x )
remainingNodes[x].first = x;
std::random_shuffle( remainingNodes.begin(), remainingNodes.end() );
for ( int x = 0; x < ( int ) numberOfNodes; ++x )
nodeData[remainingNodes[x].first].bias = x;
qDebug( "Initialise Elimination PQ... " );
_LogItem statistics0;
statistics0.updating = _Timestamp();
statistics0.iteration = 0;
#pragma omp parallel
{
_ThreadData* data = threadData[omp_get_thread_num()];
#pragma omp for schedule ( guided )
for ( int x = 0; x < ( int ) numberOfNodes; ++x ) {
nodePriority[x] = _Evaluate( data, &nodeData[x], x );
}
}
qDebug( "done" );
statistics0.updating = _Timestamp() - statistics0.updating;
log.Insert( statistics0 );
log.PrintHeader();
statistics0.PrintStatistics();
while ( levelID < numberOfNodes ) {
_LogItem statistics;
statistics.iteration = iteration++;
const int last = ( int ) remainingNodes.size();
//determine independent node set
double timeLast = _Timestamp();
#pragma omp parallel
{
_ThreadData* const data = threadData[omp_get_thread_num()];
#pragma omp for schedule ( guided )
for ( int i = 0; i < last; ++i ) {
const NodeID node = remainingNodes[i].first;
remainingNodes[i].second = _IsIndependent( nodePriority, nodeData, data, node );
}
}
_NodePartitionor functor;
const std::vector < std::pair < NodeID, bool > >::const_iterator first = stable_partition( remainingNodes.begin(), remainingNodes.end(), functor );
const int firstIndependent = first - remainingNodes.begin();
statistics.nodes = last - firstIndependent;
statistics.independent += _Timestamp() - timeLast;
timeLast = _Timestamp();
//contract independent nodes
#pragma omp parallel
{
_ThreadData* const data = threadData[omp_get_thread_num()];
#pragma omp for schedule ( guided ) nowait
for ( int position = firstIndependent ; position < last; ++position ) {
NodeID x = remainingNodes[position].first;
_Contract< false > ( data, x );
nodePriority[x] = -1;
}
std::sort( data->insertedEdges.begin(), data->insertedEdges.end() );
}
statistics.contraction += _Timestamp() - timeLast;
timeLast = _Timestamp();
#pragma omp parallel
{
_ThreadData* const data = threadData[omp_get_thread_num()];
#pragma omp for schedule ( guided ) nowait
for ( int position = firstIndependent ; position < last; ++position ) {
NodeID x = remainingNodes[position].first;
_DeleteIncommingEdges( data, x );
}
}
statistics.removing += _Timestamp() - timeLast;
timeLast = _Timestamp();
//insert new edges
for ( int threadNum = 0; threadNum < maxThreads; ++threadNum ) {
_ThreadData& data = *threadData[threadNum];
for ( int i = 0; i < ( int ) data.insertedEdges.size(); ++i ) {
const _ImportEdge& edge = data.insertedEdges[i];
_graph->InsertEdge( edge.source, edge.target, edge.data );
}
std::vector< _ImportEdge >().swap( data.insertedEdges );
}
statistics.inserting += _Timestamp() - timeLast;
timeLast = _Timestamp();
//update priorities
#pragma omp parallel
{
_ThreadData* const data = threadData[omp_get_thread_num()];
#pragma omp for schedule ( guided ) nowait
for ( int position = firstIndependent ; position < last; ++position ) {
NodeID x = remainingNodes[position].first;
_UpdateNeighbours( &nodePriority, &nodeData, data, x );
}
}
statistics.updating += _Timestamp() - timeLast;
timeLast = _Timestamp();
//output some statistics
statistics.PrintStatistics();
//qDebug( wxT( "Printed" ) );
//remove contracted nodes from the pool
levelID += last - firstIndependent;
remainingNodes.resize( firstIndependent );
std::vector< std::pair< NodeID, bool > >( remainingNodes ).swap( remainingNodes );
log.Insert( statistics );
}
for ( int threadNum = 0; threadNum < maxThreads; threadNum++ ) {
_witnessList.insert( _witnessList.end(), threadData[threadNum]->witnessList.begin(), threadData[threadNum]->witnessList.end() );
delete threadData[threadNum];
}
log.PrintSummary();
qDebug( "Total Time: %lf s", log.GetSum().GetTotalTime() );
}
template< class Edge >
void GetEdges( std::vector< Edge >* edges ) {
NodeID numberOfNodes = _graph->GetNumberOfNodes();
for ( NodeID node = 0; node < numberOfNodes; ++node ) {
for ( _DynamicGraph::EdgeIterator edge = _graph->BeginEdges( node ), endEdges = _graph->EndEdges( node ); edge != endEdges; ++edge ) {
const NodeID target = _graph->GetTarget( edge );
const _EdgeData& data = _graph->GetEdgeData( edge );
Edge newEdge;
newEdge.source = node;
newEdge.target = target;
newEdge.data.distance = data.distance;
newEdge.data.shortcut = data.shortcut;
if ( data.shortcut )
newEdge.data.middle = data.middle;
else
newEdge.data.id = data.id;
newEdge.data.forward = data.forward;
newEdge.data.backward = data.backward;
edges->push_back( newEdge );
}
}
}
template< class Edge >
void GetLoops( std::vector< Edge >* edges ) {
for ( unsigned i = 0; i < _loops.size(); i++ ) {
Edge newEdge;
newEdge.source = _loops[i].source;
newEdge.target = _loops[i].target;
newEdge.data.distance = _loops[i].data.distance;
newEdge.data.shortcut = _loops[i].data.shortcut;
newEdge.data.id = _loops[i].data.id;
newEdge.data.forward = _loops[i].data.forward;
newEdge.data.backward = _loops[i].data.backward;
edges->push_back( newEdge );
}
}
void GetWitnessList( std::vector< Witness >& list ) {
list = _witnessList;
}
private:
double _Timestamp() {
static Timer timer;
return ( double ) timer.elapsed() / 1000;
}
bool _ConstructCH( _DynamicGraph* _graph );
void _Dijkstra( const unsigned maxDistance, const int maxNodes, _ThreadData* const data ){
_Heap& heap = data->heap;
int nodes = 0;
while ( heap.Size() > 0 ) {
const NodeID node = heap.DeleteMin();
const unsigned distance = heap.GetKey( node );
if ( nodes++ > maxNodes )
return;
//Destination settled?
if ( distance > maxDistance )
return;
//iterate over all edges of node
for ( _DynamicGraph::EdgeIterator edge = _graph->BeginEdges( node ), endEdges = _graph->EndEdges( node ); edge != endEdges; ++edge ) {
const _EdgeData& data = _graph->GetEdgeData( edge );
if ( !data.forward )
continue;
const NodeID to = _graph->GetTarget( edge );
const unsigned toDistance = distance + data.distance;
//New Node discovered -> Add to Heap + Node Info Storage
if ( !heap.WasInserted( to ) )
heap.Insert( to, toDistance, _HeapData() );
//Found a shorter Path -> Update distance
else if ( toDistance < heap.GetKey( to ) ) {
heap.DecreaseKey( to, toDistance );
}
}
}
}
double _Evaluate( _ThreadData* const data, _PriorityData* const nodeData, NodeID node ){
_ContractionInformation stats;
//perform simulated contraction
_Contract< true > ( data, node, &stats );
// Result will contain the priority
double result;
if ( stats.edgesDeleted == 0 || stats.originalEdgesDeleted == 0 )
result = 1 * nodeData->depth;
else
result = 2 * ((( double ) stats.edgesAdded ) / stats.edgesDeleted ) + 1 * ((( double ) stats.originalEdgesAdded ) / stats.originalEdgesDeleted ) + 1 * nodeData->depth;
assert( result >= 0 );
return result;
}
template< bool Simulate > bool _Contract( _ThreadData* const data, NodeID node, _ContractionInformation* const stats = NULL ) {
_Heap& heap = data->heap;
//std::vector< Witness >& witnessList = data->witnessList;
int insertedEdgesSize = data->insertedEdges.size();
std::vector< _ImportEdge >& insertedEdges = data->insertedEdges;
for ( _DynamicGraph::EdgeIterator inEdge = _graph->BeginEdges( node ), endInEdges = _graph->EndEdges( node ); inEdge != endInEdges; ++inEdge ) {
const _EdgeData& inData = _graph->GetEdgeData( inEdge );
const NodeID source = _graph->GetTarget( inEdge );
if ( Simulate ) {
assert( stats != NULL );
stats->edgesDeleted++;
stats->originalEdgesDeleted += inData.originalEdges;
}
if ( !inData.backward )
continue;
heap.Clear();
heap.Insert( source, 0, _HeapData() );
if ( node != source )
heap.Insert( node, inData.distance, _HeapData() );
unsigned maxDistance = 0;
for ( _DynamicGraph::EdgeIterator outEdge = _graph->BeginEdges( node ), endOutEdges = _graph->EndEdges( node ); outEdge != endOutEdges; ++outEdge ) {
const _EdgeData& outData = _graph->GetEdgeData( outEdge );
if ( !outData.forward )
continue;
const NodeID target = _graph->GetTarget( outEdge );
const unsigned pathDistance = inData.distance + outData.distance;
maxDistance = std::max( maxDistance, pathDistance );
if ( !heap.WasInserted( target ) )
heap.Insert( target, pathDistance, _HeapData() );
else if ( pathDistance < heap.GetKey( target ) )
heap.DecreaseKey( target, pathDistance );
}
if ( Simulate )
_Dijkstra( maxDistance, 500, data );
else
_Dijkstra( maxDistance, 1000, data );
for ( _DynamicGraph::EdgeIterator outEdge = _graph->BeginEdges( node ), endOutEdges = _graph->EndEdges( node ); outEdge != endOutEdges; ++outEdge ) {
const _EdgeData& outData = _graph->GetEdgeData( outEdge );
if ( !outData.forward )
continue;
const NodeID target = _graph->GetTarget( outEdge );
const int pathDistance = inData.distance + outData.distance;
const int distance = heap.GetKey( target );
if ( pathDistance <= distance ) {
if ( Simulate ) {
assert( stats != NULL );
stats->edgesAdded += 2;
stats->originalEdgesAdded += 2 * ( outData.originalEdges + inData.originalEdges );
} else {
_ImportEdge newEdge;
newEdge.source = source;
newEdge.target = target;
newEdge.data.distance = pathDistance;
newEdge.data.forward = true;
newEdge.data.backward = false;
newEdge.data.middle = node;
newEdge.data.shortcut = true;
newEdge.data.originalEdges = outData.originalEdges + inData.originalEdges;
insertedEdges.push_back( newEdge );
std::swap( newEdge.source, newEdge.target );
newEdge.data.forward = false;
newEdge.data.backward = true;
insertedEdges.push_back( newEdge );
}
}
/*else if ( !Simulate ) {
Witness witness;
witness.source = source;
witness.target = target;
witness.middle = node;
witnessList.push_back( witness );
}*/
}
}
if ( !Simulate ) {
for ( int i = insertedEdgesSize, iend = insertedEdges.size(); i < iend; i++ ) {
bool found = false;
for ( int other = i + 1 ; other < iend ; ++other ) {
if ( insertedEdges[other].source != insertedEdges[i].source )
continue;
if ( insertedEdges[other].target != insertedEdges[i].target )
continue;
if ( insertedEdges[other].data.distance != insertedEdges[i].data.distance )
continue;
if ( insertedEdges[other].data.shortcut != insertedEdges[i].data.shortcut )
continue;
insertedEdges[other].data.forward |= insertedEdges[i].data.forward;
insertedEdges[other].data.backward |= insertedEdges[i].data.backward;
found = true;
break;
}
if ( !found )
insertedEdges[insertedEdgesSize++] = insertedEdges[i];
}
insertedEdges.resize( insertedEdgesSize );
}
return true;
}
bool _DeleteIncommingEdges( _ThreadData* const data, NodeID node ) {
std::vector< NodeID >& neighbours = data->neighbours;
neighbours.clear();
//find all neighbours
for ( _DynamicGraph::EdgeIterator e = _graph->BeginEdges( node ) ; e < _graph->EndEdges( node ) ; ++e ) {
const NodeID u = _graph->GetTarget( e );
if ( u == node )
continue;
neighbours.push_back( u );
}
//eliminate duplicate entries ( forward + backward edges )
std::sort( neighbours.begin(), neighbours.end() );
neighbours.resize( std::unique( neighbours.begin(), neighbours.end() ) - neighbours.begin() );
for ( int i = 0, e = ( int ) neighbours.size(); i < e; ++i ) {
const NodeID u = neighbours[i];
_graph->DeleteEdgesTo( u, node );
}
return true;
}
bool _UpdateNeighbours( std::vector< double >* priorities, std::vector< _PriorityData >* const nodeData, _ThreadData* const data, NodeID node ) {
std::vector< NodeID >& neighbours = data->neighbours;
neighbours.clear();
//find all neighbours
for ( _DynamicGraph::EdgeIterator e = _graph->BeginEdges( node ) ; e < _graph->EndEdges( node ) ; ++e ) {
const NodeID u = _graph->GetTarget( e );
if ( u == node )
continue;
neighbours.push_back( u );
( *nodeData )[u].depth = std::max(( *nodeData )[node].depth + 1, ( *nodeData )[u].depth );
}
//eliminate duplicate entries ( forward + backward edges )
std::sort( neighbours.begin(), neighbours.end() );
neighbours.resize( std::unique( neighbours.begin(), neighbours.end() ) - neighbours.begin() );
for ( int i = 0, e = ( int ) neighbours.size(); i < e; ++i ) {
const NodeID u = neighbours[i];
( *priorities )[u] = _Evaluate( data, &( *nodeData )[u], u );
}
return true;
}
bool _IsIndependent( const std::vector< double >& priorities, const std::vector< _PriorityData >& nodeData, _ThreadData* const data, NodeID node ) {
const double priority = priorities[node];
std::vector< NodeID >& neighbours = data->neighbours;
neighbours.clear();
for ( _DynamicGraph::EdgeIterator e = _graph->BeginEdges( node ) ; e < _graph->EndEdges( node ) ; ++e ) {
const NodeID target = _graph->GetTarget( e );
const double targetPriority = priorities[target];
assert( targetPriority >= 0 );
//found a neighbour with lower priority?
if ( priority > targetPriority )
return false;
//tie breaking
if ( priority == targetPriority && nodeData[node].bias < nodeData[target].bias )
return false;
neighbours.push_back( target );
}
std::sort( neighbours.begin(), neighbours.end() );
neighbours.resize( std::unique( neighbours.begin(), neighbours.end() ) - neighbours.begin() );
//examine all neighbours that are at most 2 hops away
for ( std::vector< NodeID >::const_iterator i = neighbours.begin(), lastNode = neighbours.end(); i != lastNode; ++i ) {
const NodeID u = *i;
for ( _DynamicGraph::EdgeIterator e = _graph->BeginEdges( u ) ; e < _graph->EndEdges( u ) ; ++e ) {
const NodeID target = _graph->GetTarget( e );
const double targetPriority = priorities[target];
assert( targetPriority >= 0 );
//found a neighbour with lower priority?
if ( priority > targetPriority )
return false;
//tie breaking
if ( priority == targetPriority && nodeData[node].bias < nodeData[target].bias )
return false;
}
}
return true;
}
_DynamicGraph* _graph;
std::vector< Witness > _witnessList;
std::vector< _ImportEdge > _loops;
};
#endif // CONTRACTOR_H_INCLUDED