Craig Tiller | 897e4fe | 2015-12-22 15:03:40 -0800 | [diff] [blame] | 1 | // Copyright 2015, Google Inc. |
| 2 | // All rights reserved. |
| 3 | // |
| 4 | // Redistribution and use in source and binary forms, with or without |
| 5 | // modification, are permitted provided that the following conditions are |
| 6 | // met: |
| 7 | // |
| 8 | // * Redistributions of source code must retain the above copyright |
| 9 | // notice, this list of conditions and the following disclaimer. |
| 10 | // * Redistributions in binary form must reproduce the above |
| 11 | // copyright notice, this list of conditions and the following disclaimer |
| 12 | // in the documentation and/or other materials provided with the |
| 13 | // distribution. |
| 14 | // * Neither the name of Google Inc. nor the names of its |
| 15 | // contributors may be used to endorse or promote products derived from |
| 16 | // this software without specific prior written permission. |
| 17 | // |
| 18 | // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
| 19 | // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
| 20 | // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR |
| 21 | // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT |
| 22 | // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
| 23 | // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT |
| 24 | // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
| 25 | // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
| 26 | // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| 27 | // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
| 28 | // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| 29 | |
| 30 | using Newtonsoft.Json; |
Jan Tattermusch | e003f01 | 2015-05-22 09:34:50 -0700 | [diff] [blame] | 31 | using Newtonsoft.Json.Linq; |
| 32 | using System; |
| 33 | using System.Collections.Generic; |
| 34 | using System.IO; |
| 35 | using System.Linq; |
| 36 | using System.Text; |
| 37 | using System.Threading.Tasks; |
| 38 | |
Jan Tattermusch | 73f9dbb | 2015-09-09 09:39:14 -0700 | [diff] [blame] | 39 | namespace Routeguide |
Jan Tattermusch | e003f01 | 2015-05-22 09:34:50 -0700 | [diff] [blame] | 40 | { |
Jan Tattermusch | 121c4d1 | 2015-08-31 10:27:27 -0700 | [diff] [blame] | 41 | /// <summary> |
| 42 | /// Utility methods for the route guide example. |
| 43 | /// </summary> |
Jan Tattermusch | e003f01 | 2015-05-22 09:34:50 -0700 | [diff] [blame] | 44 | public static class RouteGuideUtil |
| 45 | { |
| 46 | public const string DefaultFeaturesFile = "route_guide_db.json"; |
| 47 | |
| 48 | private const double CoordFactor = 1e7; |
| 49 | |
| 50 | /// <summary> |
| 51 | /// Indicates whether the given feature exists (i.e. has a valid name). |
| 52 | /// </summary> |
Jan Tattermusch | 121c4d1 | 2015-08-31 10:27:27 -0700 | [diff] [blame] | 53 | public static bool Exists(this Feature feature) |
Jan Tattermusch | e003f01 | 2015-05-22 09:34:50 -0700 | [diff] [blame] | 54 | { |
| 55 | return feature != null && (feature.Name.Length != 0); |
| 56 | } |
| 57 | |
Jan Tattermusch | 121c4d1 | 2015-08-31 10:27:27 -0700 | [diff] [blame] | 58 | public static double GetLatitude(this Point point) |
Jan Tattermusch | e003f01 | 2015-05-22 09:34:50 -0700 | [diff] [blame] | 59 | { |
| 60 | return point.Latitude / CoordFactor; |
| 61 | } |
| 62 | |
Jan Tattermusch | 121c4d1 | 2015-08-31 10:27:27 -0700 | [diff] [blame] | 63 | public static double GetLongitude(this Point point) |
Jan Tattermusch | e003f01 | 2015-05-22 09:34:50 -0700 | [diff] [blame] | 64 | { |
| 65 | return point.Longitude / CoordFactor; |
| 66 | } |
| 67 | |
| 68 | /// <summary> |
Jan Tattermusch | 121c4d1 | 2015-08-31 10:27:27 -0700 | [diff] [blame] | 69 | /// Calculate the distance between two points using the "haversine" formula. |
| 70 | /// This code was taken from http://www.movable-type.co.uk/scripts/latlong.html. |
| 71 | /// </summary> |
| 72 | /// <param name="start">the starting point</param> |
| 73 | /// <param name="end">the end point</param> |
| 74 | /// <returns>the distance between the points in meters</returns> |
| 75 | public static double GetDistance(this Point start, Point end) |
| 76 | { |
| 77 | double lat1 = start.GetLatitude(); |
| 78 | double lat2 = end.GetLatitude(); |
| 79 | double lon1 = start.GetLongitude(); |
| 80 | double lon2 = end.GetLongitude(); |
| 81 | int r = 6371000; // metres |
| 82 | double phi1 = ToRadians(lat1); |
| 83 | double phi2 = ToRadians(lat2); |
| 84 | double deltaPhi = ToRadians(lat2 - lat1); |
| 85 | double deltaLambda = ToRadians(lon2 - lon1); |
| 86 | |
| 87 | double a = Math.Sin(deltaPhi / 2) * Math.Sin(deltaPhi / 2) + Math.Cos(phi1) * Math.Cos(phi2) * Math.Sin(deltaLambda / 2) * Math.Sin(deltaLambda / 2); |
| 88 | double c = 2 * Math.Atan2(Math.Sqrt(a), Math.Sqrt(1 - a)); |
| 89 | |
| 90 | return r * c; |
| 91 | } |
| 92 | |
| 93 | /// <summary> |
| 94 | /// Returns <c>true</c> if rectangular area contains given point. |
| 95 | /// </summary> |
| 96 | public static bool Contains(this Rectangle rectangle, Point point) |
| 97 | { |
| 98 | int left = Math.Min(rectangle.Lo.Longitude, rectangle.Hi.Longitude); |
| 99 | int right = Math.Max(rectangle.Lo.Longitude, rectangle.Hi.Longitude); |
| 100 | int top = Math.Max(rectangle.Lo.Latitude, rectangle.Hi.Latitude); |
| 101 | int bottom = Math.Min(rectangle.Lo.Latitude, rectangle.Hi.Latitude); |
| 102 | return (point.Longitude >= left && point.Longitude <= right && point.Latitude >= bottom && point.Latitude <= top); |
| 103 | } |
| 104 | |
| 105 | private static double ToRadians(double val) |
| 106 | { |
| 107 | return (Math.PI / 180) * val; |
| 108 | } |
| 109 | |
| 110 | /// <summary> |
Jan Tattermusch | e003f01 | 2015-05-22 09:34:50 -0700 | [diff] [blame] | 111 | /// Parses features from a JSON file. |
| 112 | /// </summary> |
| 113 | public static List<Feature> ParseFeatures(string filename) |
| 114 | { |
| 115 | var features = new List<Feature>(); |
| 116 | var jsonFeatures = JsonConvert.DeserializeObject<List<JsonFeature>>(File.ReadAllText(filename)); |
| 117 | |
Jan Tattermusch | e003f01 | 2015-05-22 09:34:50 -0700 | [diff] [blame] | 118 | foreach(var jsonFeature in jsonFeatures) |
| 119 | { |
Jan Tattermusch | 121c4d1 | 2015-08-31 10:27:27 -0700 | [diff] [blame] | 120 | features.Add(new Feature |
| 121 | { |
| 122 | Name = jsonFeature.name, |
| 123 | Location = new Point { Longitude = jsonFeature.location.longitude, Latitude = jsonFeature.location.latitude} |
| 124 | }); |
Jan Tattermusch | e003f01 | 2015-05-22 09:34:50 -0700 | [diff] [blame] | 125 | } |
| 126 | return features; |
| 127 | } |
| 128 | |
| 129 | private class JsonFeature |
| 130 | { |
| 131 | public string name; |
| 132 | public JsonLocation location; |
| 133 | } |
| 134 | |
| 135 | private class JsonLocation |
| 136 | { |
| 137 | public int longitude; |
| 138 | public int latitude; |
| 139 | } |
| 140 | } |
| 141 | } |