private ClusteredLocation <T> GetClusterForThisSector(List <ClusteredLocationRect <T> > clusters, LocationRect sector)
{
foreach (var cluster in clusters)
{
if (cluster.LocationRect.Intersects(sector))
{
return(cluster);
}
}
var newCluster = new ClusteredLocationRect <T>(sector);
clusters.Add(newCluster);
return(newCluster);
}
private ClusteredLocation <T> GetClusterForThisPoint(List <ClusteredLocationRect <T> > clusters, Position location, double thresholdLat, double thresholdLon)
{
foreach (var cluster in clusters)
{
if (cluster.LocationRect.Contains(location))
{
return(cluster);
}
}
var clusterRect = new LocationRect();
var nw = new Position(this.EnsureLatitude(location.Latitude + thresholdLat), this.EnsureLongitude(location.Longitude - thresholdLon));
var se = new Position(this.EnsureLatitude(location.Latitude - thresholdLat), this.EnsureLongitude(location.Longitude + thresholdLon));
clusterRect.Northwest = nw;
clusterRect.Southeast = se;
var newCluster = new ClusteredLocationRect <T>(clusterRect);
clusters.Add(newCluster);
return(newCluster);
}
private static void UpdateItemsSource(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
var map = d as Map;
var newPushPinCollection = e.NewValue as IEnumerable <IClusteredGeoObject>;
if (newPushPinCollection != null && newPushPinCollection.Any() && map != null)
{
// Read dependency properties
var pushpinTemplate = GetPushpinTemplate(d);
var clusterPushpinTemplate = GetClusterTemplate(d);
////var clusteringDistance = GetClusteringDistance(d);
// Perform clustering
var visibleAreaTopLeft = map.ConvertViewportPointToGeoCoordinate(new Point(0, 0));
var visibleAreaBottomRight = map.ConvertViewportPointToGeoCoordinate(new Point(map.ActualWidth, map.ActualHeight));
var boundingRectangle = LocationRect.CreateLocationRect(visibleAreaTopLeft.ToPosition(), visibleAreaBottomRight.ToPosition());
//var clusterer = new SectorClusterer<IClusteredGeoObject>();
var clusterer = new RectangularClusterer <IClusteredGeoObject>();
//var stopwatch = new Stopwatch();
//stopwatch.Start();
IEnumerable <IClusteredLocation <IClusteredGeoObject> > clusteredLocations = clusterer.Cluster(newPushPinCollection, boundingRectangle, map.ZoomLevel);
if (map.ZoomLevel >= 18)
{
clusteredLocations = clusteredLocations.SelectMany(x => x.ClusteredItems).Select(
clusteredGeoObject =>
{
var rect = new ClusteredLocationRect <IClusteredGeoObject>(boundingRectangle);
rect.Add(clusteredGeoObject);
return(rect);
}).ToList();
}
//stopwatch.Stop();
//Console.WriteLine("UPDATED CLUSTER IN {0}ms", stopwatch.ElapsedMilliseconds);
// Update map on UI
map.Dispatcher.BeginInvoke(
() =>
{
// Remove layer which hosts pushpins
var clusteredPushpinLayer = map.Layers.FirstOrDefault(x => x.All(y => y.Content is IClusteredLocation <IClusteredGeoObject>));
map.Layers.Remove(clusteredPushpinLayer);
// Create new layer
var layer = new MapLayer();
// The descending-by-latitude ordering makes sure the pins are not overlapping eachother
Position lastGeoCoordinate = Position.Unknown;
foreach (var pushPinModel in clusteredLocations.OrderByDescending(p => p.Location.Latitude))
{
var mapOverlay = new MapOverlay
{
GeoCoordinate = new GeoCoordinate(pushPinModel.Location.Latitude, pushPinModel.Location.Longitude),
Content = pushPinModel
};
if (pushPinModel.IsClustered)
{
mapOverlay.ContentTemplate = clusterPushpinTemplate;
mapOverlay.PositionOrigin = new System.Windows.Point(0.5, 0.5);
}
else
{
mapOverlay.ContentTemplate = pushpinTemplate;
// In case two/more pins have the same GPS position, we add a random offset to longitude/latitude.
if (Math.Abs(pushPinModel.Location.Latitude - lastGeoCoordinate.Latitude) < 0.00005 &&
Math.Abs(pushPinModel.Location.Longitude - lastGeoCoordinate.Longitude) < 0.00005)
{
mapOverlay.GeoCoordinate = lastGeoCoordinate.WithRandomOffset().ToGeoCoordinate();
}
lastGeoCoordinate = pushPinModel.Location;
}
layer.Add(mapOverlay);
}
// Finally, add all items (pushpins, clusters and current location) to the map.
if (layer.Any())
{
map.Layers.Insert(ItemsSourceLayerIndex, layer);
}
});
}
}
