Drivetime Polygons with MapPoint and Bing Maps

There was a time, a few years ago, when the MapPoint CD could regularly be found in my computer’s CD drive… back then, it was the best tool for examining maps, plotting routes, and creating your own sets of pushpin data.

Nowadays, Bing maps, Google maps, and other online web-mapping providers provide much of the functionality that could previously only be found in desktop applications such as MapPoint, for free, with continuously updated road and aerial imagery data. The terabytes of global data that sit behind web applications such as Bing Maps could never easily be packaged up and distributed in a desktop application any more. And since these webservices are readily available from any web browser, (including almost all new mobile phones), there are less obvious reasons why you’d still want to use the MapPoint desktop application on your computer.

However, there are still some functions that MapPoint provides that are not easily available in Bing Maps or Google Maps (or, as far as I’m aware, any other web-mapping providers). One of these features is the ability to plot drivetime polygons – the area containing all those places that can be reached by road within a certain amount of time starting from a particular location.

Fortunately, MapPoint can be accessed through a COM interface, which means that we can create a drivetime polygon programmatically through code, and then export it as a SQL Server geography polygon or Bing Maps polygon to display using the Bing Maps control.

To do so, you first need to import a reference to the MapPoint Object Library into your application. Create a new Visual Studio project, select Add Reference from the Project menu, select the COM tab, and scroll down to select the Microsoft MapPoint Object Library.

Note that I’m using Microsoft MapPoint Europe 2010, so my library is version 17.0 – if you have a different version installed on your computer then the name of the library will differ accordingly, but you should still be able to use the same code.

Once you’ve imported the COM assembly, you can access the MapPoint map functions via the ApplicationClass of the MapPoint namespace. The following code demonstrates a simple C# console application that initialises the MapPoint application, creates a drivetime polygon that determines all locations that can be reached within 60 minutes drive from “10 Downing Street, London”, and then retrieves the points in those shapes and converts them to Well-Known Text:

using System;
using System.Collections.Generic;
using System.Text;

namespace ConsoleApplication1
{
    class Program
    {
        static void Main(string[] args)
        {

            MapPoint.ApplicationClass app = new MapPoint.ApplicationClass();
            MapPoint.Map map = app.ActiveMap;

            object index = 1;
            MapPoint.Location location =
       (MapPoint.Location)map.FindResults("10 Downing Street, London, England").get_Item(ref index);

            //Add a 60 minute drivetime zone around a location
            MapPoint.Shape shape =
               map.Shapes.AddDrivetimeZone(location,
                          60 * MapPoint.GeoTimeConstants.geoOneMinute);

            string WKT = "POLYGON((";

            //Now get the vertices for this polygon
            object[] vertices = shape.Vertices as object[];
            foreach (object vertex in vertices)
            {
                MapPoint.Location loc = vertex as MapPoint.Location;
                WKT = WKT + loc.Longitude.ToString() + " " + loc.Latitude.ToString() + ", ";
            }
            WKT = WKT.Substring(0, WKT.Length - 2);
            WKT = WKT + "))";
            Console.Write(WKT);
        }
    }
}

Drivetime polygons created using this method can be stored in SQL Server 2008’s geography datatype, and then retrieved and plotted on Bing Maps.

Here’s some drivetime polygons generated using the method described above illustrating those areas reachable within  20 minutes, 40 minutes, and 60 minutes drive starting from my house in Norwich, displayed on Bing Maps v7:

using System;

using System.Collections.Generic;

using System.Text;

namespace ConsoleApplication1

{

    class Program

    {

        static void Main(string[] args)

        {

            MapPoint.ApplicationClass app = new MapPoint.ApplicationClass();

            MapPoint.Map map = app.ActiveMap;

            object index = 1;

            MapPoint.Location location =

       (MapPoint.Location)map.FindResults("10 Downing Street, London, England").get_Item(ref index);

            //Add a 60 minute drivetime zone around a location

            MapPoint.Shape shape =

               map.Shapes.AddDrivetimeZone(location,

                          60 * MapPoint.GeoTimeConstants.geoOneMinute);

            string WKT = "POLYGON((";

            //Now get the vertices for this polygon

            object[] vertices = shape.Vertices as object[];

            foreach (object vertex in vertices)

            {

                MapPoint.Location loc = vertex as MapPoint.Location;

                WKT = WKT + loc.Longitude.ToString() + " " + loc.Latitude.ToString() + ", ";

            }

            WKT = WKT.Substring(0, WKT.Length - 2);

            WKT = WKT + "))";

            Console.Write(WKT);

        }

    }

}