MapForums

I have a jpeg of a mappoint map. The jpeg shows a picture of a polygon.

What I want to know is given that I know the length and width of the jpeg (in pixels) and the coordinates of the polygon (in lat lon). How could I convet the lat lon coordinates to x y pixel coordinates.

What i'm trying to do is show an this image in a vb .net form and then overlay the image using GDI+ with an interactive polygon. The problem I obviously have is knowing where to plot my polygon.

Any ideas would be greatly appreciated.

Thanks

Are you using MapPoint 2006, or the MapPoint Web Service? If it is the web service, there is a function to handle convert to lat/long which is pretty nice. Once you save a map off in MapPoint 2006 (or earlier) there's not really any way to reference it again from within the COM interface, it's just a gif without a bounding reference. Perhaps someone else has done a hack to workaround this, but I don't know of anyway to do it.

Mark M - MSFT

Hi,

You can use XYToLocation to convert x,y pixel coordinates to a Location object, and LocationToX and LocationToY to find the x,y pixel coordinates from a Location object.

If I have understeand your question then I think this should be enough to do what you wants to do.

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rgds, Wilfried Mestdagh
www.mestdagh.biz
MapPoint coding demo
Order MapPoint 2009 with Routing and User Tools Spreadsheet

Not quite what I need to do but it has given me an idea. Thanks for your help

I know its a late reply.

It sounds like you have a image of a map and you know the co-ordinates of the 4 corners.
You also know the dimensions of the map image
It sounds like a matter of dividing the change of degrees by the pixels to determine how many degrees (or portions thereof) are passed per pixel

The map linked to below is from MP2002, and the target location is placed using a similiar technique
Map

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Mike Mueller
Lannon Fire Department

Hi ,

I want to plot a point in a map when lattitude and longitude is given.

I have a .jpg image and i know some of the x y cordinates lattitude and longitude. No other information is available. Now i will be given with a lattiude and longitude and then i have to calculate the x y in the .jpeg image with.

Do any of you have some formulas or techinques to do this.

Please help me

Regards
Anish Mathew

Hi,

depends on the zoom factor and projection of the image. but if you know 2 points on x as and also on y as then you can calculate the latitude/longitude per pixel in both directions.

__________________
rgds, Wilfried Mestdagh
www.mestdagh.biz
MapPoint coding demo
Order MapPoint 2009 with Routing and User Tools Spreadsheet