British National Grid

Topics: General Topics
Oct 31, 2006 at 3:51 PM
Hi,

Most, if not all, of the data I work with is coordinated in the British National Grid system. As I understand it (and I really don't!), only a few projections are natively supported, and that if I want to use one that isn't supported I will need to write the rules by which it plays, so to speak.

So firstly, has anyone else written something to cope with British National Grid, or will I need to do it myself? Obviously I'd rather not reinvent the wheel :)

If the latter, could anyone advise me as to how to go about this?

Cheer,

Dylan
Nov 9, 2006 at 5:31 PM
Hi

I use www. franson.com GPS Toolkit which is not expensive for c# server side tools or go to my web site www.free-gis.co.uk and look at the home page demo and js file for a JavaScript version.

Hope this is of help

Duncan
Nov 9, 2006 at 7:28 PM
British National Grid is a Transverse Mercator projection, which is supported by SharpMap. You just need to figure out the datum shift parameters for your area if you need to converted from data based on other datums. See http://en.wikipedia.org/wiki/Britishnationalgridreferencesystem for a description of the grid and projection parameters.
Nov 13, 2006 at 11:54 AM
Thanks for the replies. I will look into the things you both suggested.