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javascriptangularjsangular-google-maps

Is it possible to calculate distance between two markers in angular-google-maps?


I want to show the distance between a central marker to each another markers in its own window. Is there any way to calculate distance in angular-google-maps?

Below is the code from here.

map.html

<div id="map_canvas" ng-controller="mainCtrl">
    <ui-gmap-google-map center="map.center" zoom="map.zoom" draggable="true" options="options" bounds="map.bounds">
        <ui-gmap-markers models="randomMarkers" coords="'self'" icon="'icon'">
        </ui-gmap-markers>
    </ui-gmap-google-map>
</div>

controller.js

angular.module('appMaps', ['uiGmapgoogle-maps'])
  .controller('mainCtrl', function($scope) {
    $scope.map = {
      center: {
        latitude: 40.1451,
        longitude: -99.6680
      },
      zoom: 4,
      bounds: {}
    };
    $scope.options = {
      scrollwheel: false
    };
    var createRandomMarker = function(i, bounds, idKey) {
      var lat_min = bounds.southwest.latitude,
        lat_range = bounds.northeast.latitude - lat_min,
        lng_min = bounds.southwest.longitude,
        lng_range = bounds.northeast.longitude - lng_min;

      if (idKey == null) {
        idKey = "id";
      }

      var latitude = lat_min + (Math.random() * lat_range);
      var longitude = lng_min + (Math.random() * lng_range);
      var ret = {
        latitude: latitude,
        longitude: longitude,
        title: 'm' + i
      };
      ret[idKey] = i;
      return ret;
    };
    $scope.randomMarkers = [];
    // Get the bounds from the map once it's loaded
    $scope.$watch(function() {
      return $scope.map.bounds;
    }, function(nv, ov) {
      // Only need to regenerate once
      if (!ov.southwest && nv.southwest) {
        var markers = [];
        for (var i = 0; i < 2; i++) {
          markers.push(createRandomMarker(i, $scope.map.bounds))
        }
        $scope.randomMarkers = markers;
      }
    }, true);
  });

Solution

  • Haversine formula:

    a = sin²(Δφ/2) + cos φ1 ⋅ cos φ2 ⋅ sin²(Δλ/2)
    c = 2 ⋅ atan2( √a, √(1−a) )
    d = R ⋅ c
    

    javascript code:

    var R = 6371000; // metres
    var φ1 = lat1.toRadians();
    var φ2 = lat2.toRadians();
    var Δφ = (lat2-lat1).toRadians();
    var Δλ = (lon2-lon1).toRadians();
    
    var a = Math.sin(Δφ/2) * Math.sin(Δφ/2) +
            Math.cos(φ1) * Math.cos(φ2) *
            Math.sin(Δλ/2) * Math.sin(Δλ/2);
    var c = 2 * Math.atan2(Math.sqrt(a), Math.sqrt(1-a));
    
    var d = R * c;
    

    Source from link

    I've used this function all my distance measurement and it works well.