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Let-ends-f
161
astar/Astar.cs
161
astar/Astar.cs
@ -6,16 +6,16 @@ using OSM_Regions;
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namespace astar
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namespace astar
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{
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{
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public class Astar(ValueTuple<float, float, float, float>? priorityWeights = null, int? explorationMultiplier = null, float? nonPriorityRoadSpeedPenalty = null, RegionLoader? regionLoader = null)
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public class Astar(ValueTuple<float, float, float, float>? priorityWeights = null, ValueTuple<float, float, float, float>? optimizingWeights = null, int? explorationDistance = null, int? explorationMultiplier = null)
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{
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{
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private readonly ValueTuple<float, float, float, float> DefaultPriorityWeights = priorityWeights ?? new(0.6f, 1.05f, 0, 0);
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private readonly ValueTuple<float, float, float, float> DefaultPriorityWeights = priorityWeights ?? new(0.75f, 1f, 0.1f, 0);
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private readonly int _explorationMultiplier = explorationMultiplier ?? 120;
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private readonly ValueTuple<float, float, float, float> OptimizingWeights = optimizingWeights ?? new(0, 0.07f, 0, 0);
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private readonly float _nonPriorityRoadSpeedPenalty = nonPriorityRoadSpeedPenalty ?? 0.85f;
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private int ExplorationDistanceFromRoute = explorationDistance ?? 1200;
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private RegionLoader? rl = regionLoader;
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private int ExplorationMultiplier = explorationMultiplier ?? 65;
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public Route FindPath(float startLat, float startLon, float endLat, float endLon, float regionSize, bool car = true, PathMeasure pathing = PathMeasure.Distance, string? importFolderPath = null, ILogger? logger = null)
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public Route FindPath(float startLat, float startLon, float endLat, float endLon, float regionSize, bool car = true, PathMeasure pathing = PathMeasure.Distance, float additionalExploration = 3, string? importFolderPath = null, ILogger? logger = null)
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{
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{
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rl ??= new(regionSize, importFolderPath, logger: logger);
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RegionLoader rl = new(regionSize, importFolderPath, logger: logger);
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Graph graph = Spiral(rl, startLat, startLon, regionSize);
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Graph graph = Spiral(rl, startLat, startLon, regionSize);
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Graph endRegion = Spiral(rl, endLat, endLon, regionSize);
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Graph endRegion = Spiral(rl, endLat, endLon, regionSize);
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graph.ConcatGraph(endRegion);
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graph.ConcatGraph(endRegion);
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@ -44,19 +44,27 @@ namespace astar
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ValueTuple<Node, Node>? meetingEnds = null;
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ValueTuple<Node, Node>? meetingEnds = null;
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while (toVisitStart.Count > 0 && toVisitEnd.Count > 0)
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while (toVisitStart.Count > 0 && toVisitEnd.Count > 0)
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{
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{
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for (int i = 0; i < Math.Min(toVisitStart.Count * 0.5, 50) && meetingEnds is null; i++)
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ulong closestEndNodeId = toVisitEnd.UnorderedItems
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.MinBy(n => graph.Nodes[n.Element].DistanceTo(startNode.Value)).Element;
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Node closestEndNode = graph.Nodes[closestEndNodeId];
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if (toVisitStart.Count >= toVisitEnd.Count && meetingEnds is null)
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{
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{
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ulong closestEndNodeId = toVisitEnd.UnorderedItems.MinBy(node => graph.Nodes[node.Element].DistanceTo(graph.Nodes[toVisitStart.Peek()])).Element;
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for(int i = 0; i < Math.Min(toVisitStart.Count * 0.5, 50) && meetingEnds is null; i++)
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Node closestEndNode = graph.Nodes[closestEndNodeId];
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meetingEnds = ExploreSide(true, graph, toVisitStart, rl, priorityHelper, closestEndNode, car, DefaultPriorityWeights, pathing, logger);
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meetingEnds = ExploreSide(true, graph, toVisitStart, priorityHelper, closestEndNode, car, DefaultPriorityWeights, pathing, logger);
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}
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}
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if(meetingEnds is null)
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meetingEnds = ExploreSide(true, graph, toVisitStart, rl, priorityHelper, closestEndNode, car, DefaultPriorityWeights, pathing, logger);
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for (int i = 0; i < Math.Min(toVisitEnd.Count * 0.5, 50) && meetingEnds is null; i++)
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ulong closestStartNodeId = toVisitStart.UnorderedItems
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.MinBy(n => graph.Nodes[n.Element].DistanceTo(endNode.Value)).Element;
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Node closestStartNode = graph.Nodes[closestStartNodeId];
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if (toVisitEnd.Count >= toVisitStart.Count && meetingEnds is null)
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{
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{
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ulong closestStartNodeId = toVisitStart.UnorderedItems.MinBy(node => graph.Nodes[node.Element].DistanceTo(graph.Nodes[toVisitEnd.Peek()])).Element;
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for(int i = 0; i < Math.Min(toVisitEnd.Count * 0.5, 50) && meetingEnds is null; i++)
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Node closestStartNode = graph.Nodes[closestStartNodeId];
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meetingEnds = ExploreSide(false, graph, toVisitEnd, rl, priorityHelper, closestStartNode, car, DefaultPriorityWeights, pathing, logger);
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meetingEnds = ExploreSide(false, graph, toVisitEnd, priorityHelper, closestStartNode, car, DefaultPriorityWeights, pathing, logger);
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}
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}
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if(meetingEnds is null)
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meetingEnds = ExploreSide(false, graph, toVisitEnd, rl, priorityHelper, closestStartNode, car, DefaultPriorityWeights, pathing, logger);
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if (meetingEnds is not null)
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if (meetingEnds is not null)
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break;
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break;
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@ -65,44 +73,52 @@ namespace astar
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if(meetingEnds is null)
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if(meetingEnds is null)
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return new Route(graph, Array.Empty<Step>().ToList(), false);
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return new Route(graph, Array.Empty<Step>().ToList(), false);
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Queue<ulong> routeQueue = new();
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List<Node> routeNodes = PathFound(graph, meetingEnds.Value.Item1, meetingEnds.Value.Item2, car).Steps.Select(s => s.Node1).ToList();
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toVisitStart.EnqueueRange(toVisitEnd.UnorderedItems);
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Dictionary<ulong, int> routeQueue = toVisitStart.UnorderedItems.Select(l => l.Element).Union(toVisitEnd.UnorderedItems.Select(l => l.Element)).Where(id =>
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while(toVisitStart.Count > 0)
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{
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{
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routeQueue.Enqueue(toVisitStart.Dequeue());
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Node p = graph.Nodes[id];
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}
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return routeNodes.Any(route => route.DistanceTo(p) < ExplorationDistanceFromRoute);
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int optimizeAfterFound = graph.Nodes.Count(n => n.Value.PreviousNodeId is not null) * _explorationMultiplier; //Check another x% of unexplored Paths.
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}).ToDictionary(id => id, _ => int.MinValue);
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List<ValueTuple<Node, Node>> newMeetingEnds = Optimize(graph, routeQueue, optimizeAfterFound, car, rl, pathing, logger);
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PriorityQueue<ulong, int> combinedQueue = new();
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List<Route> routes = newMeetingEnds.Select(end => PathFound(graph, end.Item1, end.Item2, car)).ToList();
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foreach ((ulong key, int value) in routeQueue)
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routes.Add(PathFound(graph, meetingEnds.Value.Item1, meetingEnds.Value.Item2, car));
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combinedQueue.Enqueue(key, value);
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ValueTuple<Node, Node>? newMeetingEnds = Optimize(additionalExploration, graph, combinedQueue, car, rl, priorityHelper, pathing, startNode.Value, endNode.Value, logger);
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meetingEnds = newMeetingEnds ?? meetingEnds;
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return routes.MinBy(route =>
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return PathFound(graph, meetingEnds!.Value.Item1, meetingEnds.Value.Item2, car, logger);
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{
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if (pathing is PathMeasure.Distance)
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return route.Distance;
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return route.Time.Ticks;
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})!;
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}
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}
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private ValueTuple<Node, Node>? ExploreSide(bool fromStart, Graph graph, PriorityQueue<ulong, int> toVisit, PriorityHelper priorityHelper, Node goalNode, bool car, ValueTuple<float,float,float,float> ratingWeights, PathMeasure pathing, ILogger? logger = null)
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private static ValueTuple<Node, Node>? ExploreSide(bool fromStart, Graph graph, PriorityQueue<ulong, int> toVisit, RegionLoader rl, PriorityHelper priorityHelper, Node goalNode, bool car, ValueTuple<float,float,float,float> ratingWeights, PathMeasure pathing = PathMeasure.Distance, ILogger? logger = null)
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{
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{
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ulong currentNodeId = toVisit.Dequeue();
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ulong currentNodeId = toVisit.Dequeue();
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Node currentNode = graph.Nodes[currentNodeId];
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Node currentNode = graph.Nodes[currentNodeId];
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logger?.LogDebug($"Distance to goal {currentNode.DistanceTo(goalNode):00000.00}m");
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logger?.LogDebug($"Distance to goal {currentNode.DistanceTo(goalNode):00000.00}m");
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foreach ((ulong neighborId, KeyValuePair<ulong, bool> wayId) in currentNode.Neighbors)
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foreach ((ulong neighborId, KeyValuePair<ulong, bool> wayId) in currentNode.Neighbors)
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{
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{
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LoadNeighbor(graph, neighborId, wayId.Key, rl!, logger);
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if (!graph.ContainsNode(neighborId))
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graph.ConcatGraph(Graph.FromGraph(rl.LoadRegionFromNodeId(neighborId)));
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if (!graph.ContainsWay(wayId.Key))
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{
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foreach (global::Graph.Graph? g in rl.LoadRegionsFromWayId(wayId.Key))
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graph.ConcatGraph(Graph.FromGraph(g));
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}
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OSM_Graph.Way way = graph.Ways[wayId.Key];
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OSM_Graph.Way way = graph.Ways[wayId.Key];
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byte speed = SpeedHelper.GetSpeed(way, car);
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byte speed = SpeedHelper.GetSpeed(way, car);
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if(!IsNeighborReachable(speed, wayId.Value, fromStart, way, car))
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if(speed < 1)
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continue;
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if(!way.AccessPermitted())
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continue;
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continue;
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if (car && !way.IsPriorityRoad())
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speed = (byte)(speed * _nonPriorityRoadSpeedPenalty);
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if(wayId.Value && way.GetDirection() == (fromStart ? WayDirection.Backwards : WayDirection.Forwards) && car)
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continue;
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if(!wayId.Value && way.GetDirection() == (fromStart ? WayDirection.Forwards : WayDirection.Backwards) && car)
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continue;
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Node neighborNode = graph.Nodes[neighborId];
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Node neighborNode = graph.Nodes[neighborId];
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if (neighborNode.PreviousIsFromStart == !fromStart) //Check if we found the opposite End
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if (neighborNode.PreviousIsFromStart is not null &&
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neighborNode.PreviousIsFromStart != fromStart) //Check if we found the opposite End
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return fromStart ? new(currentNode, neighborNode) : new(neighborNode, currentNode);
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return fromStart ? new(currentNode, neighborNode) : new(neighborNode, currentNode);
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float metric = (currentNode.Metric ?? float.MaxValue) + (pathing is PathMeasure.Distance
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float metric = (currentNode.Metric ?? float.MaxValue) + (pathing is PathMeasure.Distance
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@ -116,56 +132,25 @@ namespace astar
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toVisit.Enqueue(neighborId,
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toVisit.Enqueue(neighborId,
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priorityHelper.CalculatePriority(currentNode, neighborNode, goalNode, speed, ratingWeights));
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priorityHelper.CalculatePriority(currentNode, neighborNode, goalNode, speed, ratingWeights));
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}
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}
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logger?.LogTrace($"Neighbor {neighborId} {neighborNode}");
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}
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}
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return null;
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return null;
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}
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}
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private List<ValueTuple<Node, Node>> Optimize(Graph graph, Queue<ulong> combinedQueue, int optimizeAfterFound, bool car, RegionLoader rl, PathMeasure pathing, ILogger? logger = null)
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private ValueTuple<Node, Node>? Optimize(float additionalExploration, Graph graph, PriorityQueue<ulong, int> combinedQueue, bool car, RegionLoader rl, PriorityHelper priorityHelper, PathMeasure pathing, Node startNode, Node goalNode, ILogger? logger = null)
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{
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{
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int currentPathLength = graph.Nodes.Values.Count(node => node.PreviousNodeId is not null);
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int currentPathLength = graph.Nodes.Values.Count(node => node.PreviousNodeId is not null);
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int optimizeAfterFound = (int)(combinedQueue.Count * additionalExploration); //Check another x% of unexplored Paths.
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logger?.LogInformation($"Path found (explored {currentPathLength} Nodes). Optimizing route. (exploring {optimizeAfterFound} additional Nodes)");
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logger?.LogInformation($"Path found (explored {currentPathLength} Nodes). Optimizing route. (exploring {optimizeAfterFound} additional Nodes)");
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List<ValueTuple<Node, Node>> newMeetingEnds = new();
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ValueTuple<Node, Node>? newMeetingEnds = null;
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while (optimizeAfterFound-- > 0 && combinedQueue.Count > 0)
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while (optimizeAfterFound-- > 0 && combinedQueue.Count > 0)
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{
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{
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ulong currentNodeId = combinedQueue.Dequeue();
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ulong nodeId = combinedQueue.Peek();
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Node currentNode = graph.Nodes[currentNodeId];
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Node node = graph.Nodes[nodeId];
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bool fromStart = (bool)currentNode.PreviousIsFromStart!;
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bool fromStart = (bool)node.PreviousIsFromStart!;
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foreach ((ulong neighborId, KeyValuePair<ulong, bool> wayId) in currentNode.Neighbors)
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newMeetingEnds = ExploreSide(fromStart, graph, combinedQueue, rl, priorityHelper, fromStart ? goalNode : startNode, car, OptimizingWeights, pathing, logger);
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{
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LoadNeighbor(graph, neighborId, wayId.Key, rl, logger);
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OSM_Graph.Way way = graph.Ways[wayId.Key];
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byte speed = SpeedHelper.GetSpeed(way, car);
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if(!IsNeighborReachable(speed, wayId.Value, fromStart, way, car))
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continue;
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if (car && !way.IsPriorityRoad())
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speed = (byte)(speed * _nonPriorityRoadSpeedPenalty);
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Node neighborNode = graph.Nodes[neighborId];
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if (neighborNode.PreviousIsFromStart is not null &&
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neighborNode.PreviousIsFromStart != fromStart) //Check if we found the opposite End
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{
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newMeetingEnds.Add(fromStart ? new(currentNode, neighborNode) : new(neighborNode, currentNode));
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}
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float metric = (currentNode.Metric ?? float.MaxValue) + (pathing is PathMeasure.Distance
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? (float)currentNode.DistanceTo(neighborNode)
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: (float)currentNode.DistanceTo(neighborNode) / speed);
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if (neighborNode.PreviousNodeId is null || (neighborNode.PreviousIsFromStart == fromStart && neighborNode.Metric > metric))
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{
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neighborNode.PreviousNodeId = currentNodeId;
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neighborNode.Metric = metric;
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neighborNode.PreviousIsFromStart = fromStart;
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combinedQueue.Enqueue(neighborId);
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}
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logger?.LogTrace($"Neighbor {neighborId} {neighborNode}");
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logger?.LogDebug($"Optimization Contingent: {optimizeAfterFound}/{combinedQueue.Count}");
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}
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}
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}
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logger?.LogDebug($"Nodes in Queue after Optimization: {combinedQueue.Count}");
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return newMeetingEnds;
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return newMeetingEnds;
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}
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}
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@ -202,32 +187,6 @@ namespace astar
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return r;
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return r;
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}
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}
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private static bool IsNeighborReachable(byte speed, bool wayDirection, bool fromStart, OSM_Graph.Way way, bool car)
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{
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if(speed < 1)
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return false;
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if(!way.AccessPermitted())
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return false;
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if(wayDirection && way.GetDirection() == (fromStart ? WayDirection.Backwards : WayDirection.Forwards) && car)
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return false;
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if(!wayDirection && way.GetDirection() == (fromStart ? WayDirection.Forwards : WayDirection.Backwards) && car)
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return false;
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return true;
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}
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private static void LoadNeighbor(Graph graph, ulong neighborId, ulong wayId, RegionLoader rl, ILogger? logger = null)
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{
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if (!graph.ContainsNode(neighborId))
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graph.ConcatGraph(Graph.FromGraph(rl.LoadRegionFromNodeId(neighborId)));
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if (!graph.ContainsWay(wayId))
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{
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logger?.LogDebug("Loading way... This will be slow.");
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foreach (global::Graph.Graph? g in rl.LoadRegionsFromWayId(wayId))
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graph.ConcatGraph(Graph.FromGraph(g));
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}
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}
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private static Graph Spiral(RegionLoader loader, float lat, float lon, float regionSize)
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private static Graph Spiral(RegionLoader loader, float lat, float lon, float regionSize)
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{
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{
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Graph? ret = Graph.FromGraph(loader.LoadRegionFromCoordinates(lat, lon));
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Graph? ret = Graph.FromGraph(loader.LoadRegionFromCoordinates(lat, lon));
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@ -2,6 +2,8 @@
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public class PriorityHelper(double totalDistance, byte maxSpeed)
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public class PriorityHelper(double totalDistance, byte maxSpeed)
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{
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{
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private readonly double _totalDistance = totalDistance;
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private readonly byte _maxSpeed = maxSpeed;
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public int CalculatePriority(Node current, Node neighbor, Node goal, byte speed, ValueTuple<float, float, float, float> ratingWeights)
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public int CalculatePriority(Node current, Node neighbor, Node goal, byte speed, ValueTuple<float, float, float, float> ratingWeights)
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{
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{
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double neighborDistanceToGoal = neighbor.DistanceTo(goal); //we want this to be small
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double neighborDistanceToGoal = neighbor.DistanceTo(goal); //we want this to be small
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@ -14,10 +16,10 @@ public class PriorityHelper(double totalDistance, byte maxSpeed)
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neighborDistanceToGoal * neighborDistanceToGoal) /
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neighborDistanceToGoal * neighborDistanceToGoal) /
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(2 * currentDistanceToGoal * currentDistanceToNeighbor)));
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(2 * currentDistanceToGoal * currentDistanceToNeighbor)));
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double speedRating = speed * 1.0 / maxSpeed * 100;
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double speedRating = speed * 1.0 / _maxSpeed * 100;
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double angleRating = 100 - (angle < 180 ? angle / 180 : (360 - angle) / 180) * 100;
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double angleRating = 100 - (angle < 180 ? angle / 180 : (360 - angle) / 180) * 100;
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double distanceImprovedRating = 100 - (neighborDistanceToGoal - currentDistanceToGoal ) / totalDistance * 100;
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double distanceImprovedRating = 100 - (neighborDistanceToGoal - currentDistanceToGoal ) / _totalDistance * 100;
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double distanceSpeedRating = ((totalDistance / maxSpeed) / (neighborDistanceToGoal / speed)) * 100;
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double distanceSpeedRating = ((_totalDistance / _maxSpeed) / (neighborDistanceToGoal / speed)) * 100;
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return (int)-(speedRating * ratingWeights.Item1 + angleRating * ratingWeights.Item2 + distanceImprovedRating * ratingWeights.Item3 + distanceSpeedRating * ratingWeights.Item4);
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return (int)-(speedRating * ratingWeights.Item1 + angleRating * ratingWeights.Item2 + distanceImprovedRating * ratingWeights.Item3 + distanceSpeedRating * ratingWeights.Item4);
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}
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}
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@ -18,7 +18,7 @@ internal static class SpeedHelper
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return car ? SpeedCar.MaxBy(s => s.Value).Value : SpeedPedestrian.MaxBy(s => s.Value).Value;
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return car ? SpeedCar.MaxBy(s => s.Value).Value : SpeedPedestrian.MaxBy(s => s.Value).Value;
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}
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}
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private static readonly Dictionary<HighwayType, byte> SpeedPedestrian = new() {
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private static Dictionary<HighwayType, byte> SpeedPedestrian = new() {
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{ HighwayType.NONE, 0 },
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{ HighwayType.NONE, 0 },
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{ HighwayType.motorway, 0 },
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{ HighwayType.motorway, 0 },
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{ HighwayType.trunk, 0 },
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{ HighwayType.trunk, 0 },
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@ -50,7 +50,7 @@ internal static class SpeedHelper
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{ HighwayType.construction, 0 }
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{ HighwayType.construction, 0 }
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};
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};
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private static readonly Dictionary<HighwayType, byte> SpeedCar = new() {
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private static Dictionary<HighwayType, byte> SpeedCar = new() {
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{ HighwayType.NONE, 0 },
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{ HighwayType.NONE, 0 },
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{ HighwayType.motorway, 120 },
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{ HighwayType.motorway, 120 },
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{ HighwayType.trunk, 80 },
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{ HighwayType.trunk, 80 },
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||||||
|
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Block a user