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RadMap supports clusterization of its layers allowing grouping of their items. This feature is extremely useful when dealing with large collections having items located close to each other.

Figure 1: Clustering

map features layers clusterization 001

Clusterization Modes

The ClusterDistance property of a certain layer is responsible for setting a distance according to which each of the layer items will be evaluated to form a group. There are two types of clusters which can be assigned to the ClusterStrategy property of the layer:

  • ElementClusterStrategy: All of the layer items are evaluated and a cluster is being created on the exact coordinates of an item within the cluster.

  • DistanceClusterStrategy: All of the layer items are evaluated and a cluster is being created on the geographic center of the items part of the cluster.

The example below creates a layer with four MapPin elements and defines clusters using ElementClusterStrategy and DistanceClusterStrategy having the same ClusterDistance.

Add Layer and Data

private void SetupLayers()
    MapLayer easternLayer = new MapLayer("CitiesLayer");

private void SetupData()
    MapPin element = new MapPin(new PointG(40.4467648, -80.01576030));
    element.Text = "Pittsburgh";
    element.BackColor = Color.Red;
    element = new MapPin(new PointG(40.8130697, -74.07439790));
    element.Text = "New York";
    element.BackColor = Color.Green;
    element = new MapPin(new PointG(42.3665137, -71.06160420));
    element.Text = "Boston";
    element.BackColor = Color.Blue;
    element = new MapPin(new PointG(43.6434661, -79.37909890));
    element.Text = "Toronto";
    element.BackColor = Color.Yellow;

Private Sub SetupLayers()
    Dim easternLayer As New MapLayer("CitiesLayer")
End Sub
Private Sub SetupData()
    Dim element As New MapPin(New PointG(40.4467648, -80.0157603))
    element.Text = "Pittsburgh"
    element.BackColor = Color.Red
    element = New MapPin(New PointG(40.8130697, -74.0743979))
    element.Text = "New York"
    element.BackColor = Color.Green
    element = New MapPin(New PointG(42.3665137, -71.0616042))
    element.Text = "Boston"
    element.BackColor = Color.Blue
    element = New MapPin(New PointG(43.6434661, -79.3790989))
    element.Text = "Toronto"
    element.BackColor = Color.Yellow
End Sub

Figure 2: Initial Result

map features layers clusterization 002


private void SetElementCluster()
    this.radMap1.Layers[0].ClusterStrategy = new ElementClusterStrategy();
    this.radMap1.Layers["CitiesLayer"].ClusterDistance = 200;

Private Sub SetElementCluster()
    Me.RadMap1.Layers(0).ClusterStrategy = New ElementClusterStrategy()
    Me.RadMap1.Layers("CitiesLayer").ClusterDistance = 200
End Sub

Figure 3: ElementClusterStrategy

map features layers clusterization 003


private void DistanceElementCluster()
    this.radMap1.Layers[0].ClusterStrategy = new DistanceClusterStrategy();
    this.radMap1.Layers["CitiesLayer"].ClusterDistance = 200;

Private Sub SetDistanceCluster()
    Me.RadMap1.Layers(0).ClusterStrategy = New DistanceClusterStrategy()
    Me.RadMap1.Layers("CitiesLayer").ClusterDistance = 200
End Sub

Figure 4: DistanceClusterStrategy

map features layers clusterization 004

See Also