Knowledge Base - Advanced Features Guide

Map Marker Clustering in Geocode Factory

Introduction

Clustering clarifies your data visualization by grouping markers that are near each other on the map. This grouping is dependent the zoom level. Based on the sample map you see below, the clustering function will draw a grid, and group the markers from each area, in one special marker that contains a number on it representing the number of individual markers it consolidated. The goal is to clarify the final view of the map by reducing the amount of clutter.

google-map-grid-clustering

google-map-grid-clustering-done

In each cluster, you see the number of included markers, and when you click on a markers, the map will zoom into this area, and then you will see more clusters or markers if you are on the level which the clustering stops.

Settings

Open the GF map manager and edit the map where you want to apply the clustering. Then select the "clustering" tab.

clustering-settings

Here you can enable the clustering by setting the 'Use clustering' to Yes. This setting is enough for a basic usage, it will use default values.

Advanced settings

Ending Zoom

The ending zoom is the zoom level at which clustering will be stopped and all individual markers will be shown. In this example we click on the bottom left "300" markers icon. The maps then zooms and there are new clusters formed. The map is now centered on this point. Now if we click on the "100" cluster, clustering is stopped and all markers are visible, even if we can zoom more. This sample is from the site www.yway.ch

cluster-zoomend-full

cluster-zoomend-middle

cluster-zoomend.end

Grid size

This value define the grid size of a cluster in pixels. Each cluster will be a square. If you want the algorithm to run faster, you can set this value larger. The default value is 60. In the following capture you will see the same map, at the same zoom. The first one has the grid set to 30 and in the second the grid is set to 120.

cluster-grid-30

cluster-grid-120

Custom images

By default, if these values are null, the clustering system uses the default, internal images as per Google Maps. You can change the default images. To do this you can define the location for GF to get the cluster images. In the parameter 'Cluster image path' enter the full URL of the root name of the folder that contains the image files to use for cluster icons. As per the Google API these images must be named numerically: "1.png, 2.png, etc..." Therefore the complete file name would be: "imagePathn.png" where n is the image file number (1, 2, etc.). Sample : /images/clusters/1.png, /images/clusters/2.png, /images/clusters/3.png, ... Cluster images size is an array of numbers containing the widths of the group of imagePathn.png image files. (The images are assumed to be square).

In this sample you can see a custom drawn image used for cluster.

clustering-sample-icons

Minimum cluster size

The minimum number of markers needed to form a cluster. The default value is 2, but you can set it to be a larger number if desired.

Applies To

Geocode Factory 3, Geocode Factory 5