using Logging; using System.Xml; using Graph; namespace OpenStreetMap_Importer { public class Importer { public static Dictionary Import(Logger logger) { XmlReader reader = XmlReader.Create(new MemoryStream(OSM_Data.map)); reader.MoveToContent(); Dictionary nodes = new Dictionary(); nodeType currentNodeType = nodeType.NULL; Node nullNode = new Node(); Node currentNode = nullNode; Way currentWay = new Way(); while (reader.Read()) { if (reader.Name == "node" && reader.IsStartElement()) { currentNodeType = nodeType.NODE; nodes.Add( Convert.ToUInt64(reader.GetAttribute("id")), new Node( Convert.ToSingle(reader.GetAttribute("lat")), Convert.ToSingle(reader.GetAttribute("lon")) ) ); } else if (reader.Name == "way") { if(currentNodeType == nodeType.WAY) { ImportWay(currentWay); logger.log(loglevel.INFO, "Way nodes: {0} Weight: {1}", currentWay.nodes.Count); } currentNodeType = nodeType.WAY; currentNode = nullNode; currentWay = new Way(); reader.GetAttribute("id"); }else if (reader.Name == "nd" && currentNodeType == nodeType.WAY){ UInt64 id = Convert.ToUInt64(reader.GetAttribute("ref")); if (!nodes.TryGetValue(id, out currentNode)) { logger.log(loglevel.DEBUG, "Node with id {0} not imported.", id); } else { currentWay.nodes.Add(currentNode); } }else if (reader.Name == "tag") { if(currentNodeType == nodeType.WAY) { string value = reader.GetAttribute("v"); switch (reader.GetAttribute("k")) { /*case "highway": break;*/ case "oneway": switch (value) { case "yes": currentWay.oneway = true; break; /*case "no": currentWay.oneway = false; break;*/ case "-1": currentWay.oneway = true; currentWay.direction = Way.wayDirection.backward; break; } break; /*case "name": break;*/ } } } } logger.log(loglevel.INFO, "Loaded. Nodes: {0}", nodes.Count); return nodes; } internal static void ImportWay(Way way) { if (way.direction == Way.wayDirection.forward) { for(int index = 0; index < way.nodes.Count - 1; index++) { Node currentNode = way.nodes[index]; Node neighborNode = way.nodes[index + 1]; ushort weight = Convert.ToUInt16(DistanceBetweenNodes(currentNode, neighborNode)); currentNode.edges.Add(new Edge(neighborNode, weight)); if (!way.oneway) neighborNode.edges.Add(new Edge(currentNode, weight)); } } else { for (int index = way.nodes.Count-1; index > 1; index--) { Node currentNode = way.nodes[index]; Node neighborNode = way.nodes[index - 1]; ushort weight = Convert.ToUInt16(DistanceBetweenNodes(currentNode, neighborNode)); currentNode.edges.Add(new Edge(neighborNode, weight)); if (!way.oneway) neighborNode.edges.Add(new Edge(currentNode, weight)); } } } internal enum nodeType { NODE, WAY, NULL } internal struct Way { public List nodes; public bool oneway; public wayDirection direction; public enum wayDirection { forward, backward } public Way() { this.nodes = new List(); this.oneway = false; this.direction = wayDirection.forward; } } private static double DistanceBetweenNodes(Node n1, Node n2) { return DistanceBetweenCoordinates(n1.lat, n1.lon, n2.lat, n2.lon); } private static double DistanceBetweenCoordinates(float lat1, float lon1, float lat2, float lon2) { const int earthRadius = 6371; double differenceLat = DegreesToRadians(lat2 - lat1); double differenceLon = DegreesToRadians(lon2 - lon1); double lat1Rads = DegreesToRadians(lat1); double lat2Rads = DegreesToRadians(lat2); double a = Math.Sin(differenceLat / 2) * Math.Sin(differenceLat / 2) + Math.Sin(differenceLon / 2) * Math.Sin(differenceLon / 2) * Math.Cos(lat1Rads) * Math.Cos(lat2Rads); double c = 2 * Math.Atan2(Math.Sqrt(a), Math.Sqrt(1 - a)); return earthRadius * c; } private static double DegreesToRadians(double deg) { return deg * Math.PI / 180.0; } private static double RadiansToDegrees(double rad) { return rad * 180.0 / Math.PI; } } }