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#include "routing/routing_algorithm.hpp"
#include "routing/base/astar_algorithm.hpp"
#include "routing/base/astar_progress.hpp"
#include "routing/road_graph.hpp"
#include "base/assert.hpp"
#include "geometry/mercator.hpp"
namespace routing
{
namespace
{
uint32_t constexpr kVisitPeriod = 4;
float constexpr kProgressInterval = 2;
double constexpr KMPH2MPS = 1000.0 / (60 * 60);
inline double TimeBetweenSec(Junction const & j1, Junction const & j2, double speedMPS)
{
ASSERT(speedMPS > 0.0, ());
ASSERT_NOT_EQUAL(j1.GetAltitude(), feature::kInvalidAltitude, ());
ASSERT_NOT_EQUAL(j2.GetAltitude(), feature::kInvalidAltitude, ());
double const distanceM = MercatorBounds::DistanceOnEarth(j1.GetPoint(), j2.GetPoint());
double const altitudeDiffM =
static_cast<double>(j2.GetAltitude()) - static_cast<double>(j1.GetAltitude());
return sqrt(distanceM * distanceM + altitudeDiffM * altitudeDiffM) / speedMPS;
}
/// A class which represents an weighted edge used by RoadGraph.
class WeightedEdge
{
public:
WeightedEdge(Junction const & target, double weight) : target(target), weight(weight) {}
inline Junction const & GetTarget() const { return target; }
inline double GetWeight() const { return weight; }
private:
Junction const target;
double const weight;
};
/// A wrapper around IRoadGraph, which makes it possible to use IRoadGraph with astar algorithms.
class RoadGraph
{
public:
using Vertex = Junction;
using Edge = WeightedEdge;
using Weight = double;
RoadGraph(IRoadGraph const & roadGraph)
: m_roadGraph(roadGraph)
, m_maxSpeedMPS(roadGraph.GetMaxSpeedKMPH() * KMPH2MPS)
{}
void GetOutgoingEdgesList(Junction const & v, vector<WeightedEdge> & adj) const
{
IRoadGraph::TEdgeVector edges;
m_roadGraph.GetOutgoingEdges(v, edges);
adj.clear();
adj.reserve(edges.size());
for (auto const & e : edges)
{
ASSERT_EQUAL(v, e.GetStartJunction(), ());
double const speedMPS = m_roadGraph.GetSpeedKMPH(e) * KMPH2MPS;
adj.emplace_back(e.GetEndJunction(), TimeBetweenSec(e.GetStartJunction(), e.GetEndJunction(), speedMPS));
}
}
void GetIngoingEdgesList(Junction const & v, vector<WeightedEdge> & adj) const
{
IRoadGraph::TEdgeVector edges;
m_roadGraph.GetIngoingEdges(v, edges);
adj.clear();
adj.reserve(edges.size());
for (auto const & e : edges)
{
ASSERT_EQUAL(v, e.GetEndJunction(), ());
double const speedMPS = m_roadGraph.GetSpeedKMPH(e) * KMPH2MPS;
adj.emplace_back(e.GetStartJunction(), TimeBetweenSec(e.GetStartJunction(), e.GetEndJunction(), speedMPS));
}
}
double HeuristicCostEstimate(Junction const & v, Junction const & w) const
{
return TimeBetweenSec(v, w, m_maxSpeedMPS);
}
private:
IRoadGraph const & m_roadGraph;
double const m_maxSpeedMPS;
};
typedef AStarAlgorithm<RoadGraph> TAlgorithmImpl;
IRoutingAlgorithm::Result Convert(TAlgorithmImpl::Result value)
{
switch (value)
{
case TAlgorithmImpl::Result::OK: return IRoutingAlgorithm::Result::OK;
case TAlgorithmImpl::Result::NoPath: return IRoutingAlgorithm::Result::NoPath;
case TAlgorithmImpl::Result::Cancelled: return IRoutingAlgorithm::Result::Cancelled;
}
ASSERT(false, ("Unexpected TAlgorithmImpl::Result value:", value));
return IRoutingAlgorithm::Result::NoPath;
}
} // namespace
string DebugPrint(IRoutingAlgorithm::Result const & value)
{
switch (value)
{
case IRoutingAlgorithm::Result::OK:
return "OK";
case IRoutingAlgorithm::Result::NoPath:
return "NoPath";
case IRoutingAlgorithm::Result::Cancelled:
return "Cancelled";
}
return string();
}
// *************************** AStar routing algorithm implementation *************************************
IRoutingAlgorithm::Result AStarRoutingAlgorithm::CalculateRoute(IRoadGraph const & graph,
Junction const & startPos,
Junction const & finalPos,
RouterDelegate const & delegate,
RoutingResult<IRoadGraph::Vertex, IRoadGraph::Weight> & path)
{
AStarProgress progress(0, 95);
uint32_t visitCount = 0;
auto onVisitJunctionFn = [&](Junction const & junction, Junction const & /* target */) {
if (++visitCount % kVisitPeriod != 0)
return;
delegate.OnPointCheck(junction.GetPoint());
auto const lastValue = progress.GetLastValue();
auto const newValue = progress.GetProgressForDirectedAlgo(junction.GetPoint());
if (newValue - lastValue > kProgressInterval)
delegate.OnProgress(newValue);
};
base::Cancellable const & cancellable = delegate;
progress.Initialize(startPos.GetPoint(), finalPos.GetPoint());
RoadGraph roadGraph(graph);
TAlgorithmImpl::Params params(roadGraph, startPos, finalPos, nullptr /* prevRoute */, cancellable,
onVisitJunctionFn, {} /* checkLength */);
TAlgorithmImpl::Result const res = TAlgorithmImpl().FindPath(params, path);
return Convert(res);
}
// *************************** AStar-bidirectional routing algorithm implementation ***********************
IRoutingAlgorithm::Result AStarBidirectionalRoutingAlgorithm::CalculateRoute(
IRoadGraph const & graph, Junction const & startPos, Junction const & finalPos,
RouterDelegate const & delegate, RoutingResult<IRoadGraph::Vertex, IRoadGraph::Weight> & path)
{
AStarProgress progress(0, 95);
uint32_t visitCount = 0;
auto onVisitJunctionFn = [&](Junction const & junction, Junction const & target) {
if (++visitCount % kVisitPeriod != 0)
return;
delegate.OnPointCheck(junction.GetPoint());
auto const lastValue = progress.GetLastValue();
auto const newValue =
progress.GetProgressForBidirectedAlgo(junction.GetPoint(), target.GetPoint());
if (newValue - lastValue > kProgressInterval)
delegate.OnProgress(newValue);
};
base::Cancellable const & cancellable = delegate;
progress.Initialize(startPos.GetPoint(), finalPos.GetPoint());
RoadGraph roadGraph(graph);
TAlgorithmImpl::Params params(roadGraph, startPos, finalPos, {} /* prevRoute */, cancellable,
onVisitJunctionFn, {} /* checkLength */);
TAlgorithmImpl::Result const res = TAlgorithmImpl().FindPathBidirectional(params, path);
return Convert(res);
}
} // namespace routing
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