OSMServer/Pathfinding/Pathfinder_Distance.cs
glax 58d1031524 Splitting Pathfinding into separate files for each type of routing.
Removing timetracking again from routing-algos (not in scope)
2023-04-09 16:17:15 +02:00

64 lines
2.3 KiB
C#

using OSMDatastructure;
using OSMDatastructure.Graph;
using OSMImporter;
namespace Pathfinding;
public static partial class Pathfinder
{
public static List<PathNode> AStarDistance(string workingDir, Coordinates start,
Coordinates goal)
{
RegionManager regionManager = new (workingDir);
ValueTuple<OsmNode?, OsmNode?> startAndEndNode = SetupNodes(start, goal, regionManager);
if (startAndEndNode.Item1 is null || startAndEndNode.Item2 is null)
return new List<PathNode>();
OsmNode goalNode = startAndEndNode.Item2!;
PriorityQueue<OsmNode, double> toVisit = new();
toVisit.Enqueue(startAndEndNode.Item1, 0);
bool stop = false;
while (toVisit.Count > 0)
{
OsmNode closestNodeToGoal = toVisit.Dequeue();
foreach (OsmEdge edge in closestNodeToGoal.edges)
{
OsmNode? neighbor = regionManager.GetNode(edge.neighborId, edge.neighborRegion);
if (neighbor is not null)
{
double newPotentialWeight =
closestNodeToGoal.currentPathWeight + Utils.DistanceBetween(closestNodeToGoal, neighbor);
if (newPotentialWeight < neighbor.currentPathWeight)
{
neighbor.previousPathNode = closestNodeToGoal;
neighbor.currentPathWeight = newPotentialWeight; //for other types of routing
neighbor.currentPathLength = newPotentialWeight;
neighbor.directDistanceToGoal = Utils.DistanceBetween(neighbor, goalNode);
if (neighbor.Equals(goalNode))
{
stop = true;
}
else if(!stop)
{
toVisit.Enqueue(neighbor, neighbor.directDistanceToGoal);
}
}
}
}
}
List<PathNode> path = new();
OsmNode? currentNode = goalNode;
while (currentNode is not null)
{
path.Add(PathNode.FromOsmNode(currentNode)!);
currentNode = currentNode.previousPathNode;
}
path.Reverse();
return path;
}
}