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Adding a world map to windows form and connect locations with lines

Hi,

I am trying tocreate a windows form with a world map as its background and connect different locations on the map.
I have informations on the latitudes and longtitudes of the locations.
Should I have a map with latitudes and longtitudes ? If not, how would I join the locations?
And if yes, how can I draw lines on the map linking different locations?

Thanks.

Regards,
Jeremy

JeremyHel Thursday, September 03, 2009 9:20 AM

Hi JeremyHel,

Based on my understanding, we can follow these steps to draw a line on the map:

1. Convert latitude & longitude coordinates to pixel coordinates.

This is an article discussing about map developing:
http://rbrundritt.spaces.live.com/blog/cns!E7DBA9A4BFD458C5!488.entry.

It includes a method which converts from latitude & longitude coordinates to pixel coordinates, this is the code snippet:

    // Converts a latlitude longitude coordinate to a pixel coordinate of a map based on the map view
    private Point LatLongToPixel(Location latlong, BestView view)
    {    //Formulas based on following article:
        //http://msdn.microsoft.com/en-us/library/bb259689.aspx

        //calcuate pixel coordinates of center point of map
        double sinLatitudeCenter = Math.Sin(view.center.Latitude * Math.PI / 180); double pixelXCenter = ((view.center.Longitude + 180) / 360) * 256 * Math.Pow(2, view.zoom); double pixelYCenter = (0.5 - Math.Log((1 + sinLatitudeCenter) / (1 - sinLatitudeCenter)) / (4 * Math.PI)) * 256 * Math.Pow(2, view.zoom);        //calculate pixel coordinate of location
        double sinLatitude = Math.Sin(latlong.Latitude * Math.PI / 180); double pixelX = ((latlong.Longitude + 180) / 360) * 256 * Math.Pow(2, view.zoom); double pixelY = (0.5 - Math.Log((1 + sinLatitude) / (1 - sinLatitude)) / (4 * Math.PI)) * 256 * Math.Pow(2, view.zoom);    //calculate top left corner pixel coordiates of map image
        double topLeftPixelX = pixelXCenter - (mapWidth / 2); double topLeftPixelY = pixelYCenter - (mapHeight / 2);    //calculate relative pixel cooridnates of location
        double x = pixelX - topLeftPixelX; double y = pixelY - topLeftPixelY; return new Point((int)Math.Floor(x), (int)Math.Floor(y));
    }

2. Draw the line.

When we get the two points, we can draw the line in the OnPaint method of the Form. This is the code snippet:

    protected override void OnPaint(PaintEventArgs e)
    {
        base.OnPaint(e);
        e.Graphics.DrawLine(Pens.Red, startPoint, endPoint);
    }

Let me know if this does not help.
Aland Li

Please mark the replies as answers if they help and unmark if they don't. This can be beneficial to other community members reading the thread.

Marked As Answer byAland LiMSFT, ModeratorFriday, September 11, 2009 2:04 AM

Aland Li Monday, September 07, 2009 3:40 AM

Jeremy:

You might want to have this topic moved to another forum. This one is for issues with Windows Forms Designer, which is not the same as "help me design a form" forum. :)

Windows Forms Designer is the design-time environment of Visual Studio, and this forum treats issues related to extending an customizing this environment and experience for custom Windows Forms controls.

Good luck.

MCP

webJose Friday, September 04, 2009 2:29 AM