| // Copyright 2015, Google Inc. |
| // All rights reserved. |
| // |
| // Redistribution and use in source and binary forms, with or without |
| // modification, are permitted provided that the following conditions are |
| // met: |
| // |
| // * Redistributions of source code must retain the above copyright |
| // notice, this list of conditions and the following disclaimer. |
| // * Redistributions in binary form must reproduce the above |
| // copyright notice, this list of conditions and the following disclaimer |
| // in the documentation and/or other materials provided with the |
| // distribution. |
| // * Neither the name of Google Inc. nor the names of its |
| // contributors may be used to endorse or promote products derived from |
| // this software without specific prior written permission. |
| // |
| // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
| // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
| // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR |
| // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT |
| // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
| // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT |
| // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
| // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
| // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
| // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| |
| using Newtonsoft.Json; |
| using Newtonsoft.Json.Linq; |
| using System; |
| using System.Collections.Generic; |
| using System.IO; |
| using System.Linq; |
| using System.Text; |
| using System.Threading.Tasks; |
| |
| namespace Routeguide |
| { |
| /// <summary> |
| /// Utility methods for the route guide example. |
| /// </summary> |
| public static class RouteGuideUtil |
| { |
| public const string DefaultFeaturesFile = "route_guide_db.json"; |
| |
| private const double CoordFactor = 1e7; |
| |
| /// <summary> |
| /// Indicates whether the given feature exists (i.e. has a valid name). |
| /// </summary> |
| public static bool Exists(this Feature feature) |
| { |
| return feature != null && (feature.Name.Length != 0); |
| } |
| |
| public static double GetLatitude(this Point point) |
| { |
| return point.Latitude / CoordFactor; |
| } |
| |
| public static double GetLongitude(this Point point) |
| { |
| return point.Longitude / CoordFactor; |
| } |
| |
| /// <summary> |
| /// Calculate the distance between two points using the "haversine" formula. |
| /// This code was taken from http://www.movable-type.co.uk/scripts/latlong.html. |
| /// </summary> |
| /// <param name="start">the starting point</param> |
| /// <param name="end">the end point</param> |
| /// <returns>the distance between the points in meters</returns> |
| public static double GetDistance(this Point start, Point end) |
| { |
| double lat1 = start.GetLatitude(); |
| double lat2 = end.GetLatitude(); |
| double lon1 = start.GetLongitude(); |
| double lon2 = end.GetLongitude(); |
| int r = 6371000; // metres |
| double phi1 = ToRadians(lat1); |
| double phi2 = ToRadians(lat2); |
| double deltaPhi = ToRadians(lat2 - lat1); |
| double deltaLambda = ToRadians(lon2 - lon1); |
| |
| double a = Math.Sin(deltaPhi / 2) * Math.Sin(deltaPhi / 2) + Math.Cos(phi1) * Math.Cos(phi2) * Math.Sin(deltaLambda / 2) * Math.Sin(deltaLambda / 2); |
| double c = 2 * Math.Atan2(Math.Sqrt(a), Math.Sqrt(1 - a)); |
| |
| return r * c; |
| } |
| |
| /// <summary> |
| /// Returns <c>true</c> if rectangular area contains given point. |
| /// </summary> |
| public static bool Contains(this Rectangle rectangle, Point point) |
| { |
| int left = Math.Min(rectangle.Lo.Longitude, rectangle.Hi.Longitude); |
| int right = Math.Max(rectangle.Lo.Longitude, rectangle.Hi.Longitude); |
| int top = Math.Max(rectangle.Lo.Latitude, rectangle.Hi.Latitude); |
| int bottom = Math.Min(rectangle.Lo.Latitude, rectangle.Hi.Latitude); |
| return (point.Longitude >= left && point.Longitude <= right && point.Latitude >= bottom && point.Latitude <= top); |
| } |
| |
| private static double ToRadians(double val) |
| { |
| return (Math.PI / 180) * val; |
| } |
| |
| /// <summary> |
| /// Parses features from a JSON file. |
| /// </summary> |
| public static List<Feature> ParseFeatures(string filename) |
| { |
| var features = new List<Feature>(); |
| var jsonFeatures = JsonConvert.DeserializeObject<List<JsonFeature>>(File.ReadAllText(filename)); |
| |
| foreach(var jsonFeature in jsonFeatures) |
| { |
| features.Add(new Feature |
| { |
| Name = jsonFeature.name, |
| Location = new Point { Longitude = jsonFeature.location.longitude, Latitude = jsonFeature.location.latitude} |
| }); |
| } |
| return features; |
| } |
| |
| private class JsonFeature |
| { |
| public string name; |
| public JsonLocation location; |
| } |
| |
| private class JsonLocation |
| { |
| public int longitude; |
| public int latitude; |
| } |
| } |
| } |