[Cartoweb-users] Measure Tool

Pierre GIRAUD pierre.giraud at camptocamp.com
Thu Oct 4 08:15:31 EDT 2007


I might be wrong but, in the current Cartoweb state, you cannot display
measurement in a different unit than the mainmap units.
In your case, the result is given in dd and is certainly not precise.

Cartoweb lacks the javascript code to allow dd -> meters conversion.
And to get correct results it would also be necessary to implement the
vicenty algorithm or something equivalent.

Patches are welcome !

Regards

Pierre

Thomas Shaw Obregon wrote:
>
> Hello there!
>
>  
>
> I have some trouble using the measure tool. When I just downloaded it,
> it worked well because the map projection of the demo stuff is meters.
> The thing here is that all my maps are in geographic coordinates
> system (lat, lon) wgs84. So when I customized the .map file with my
> data, and I tried to measure some distances, it showed me an incorrect
> result. For example if I measure an approximate distance of 800 km.,
> the dhtml prints 0.05 km.
>
>  
>
> So what can I do, in order to adjust the calculation between two
> points in a geographic coordinate data and finally get the correct
> distance in KM.
>
>  
>
> Thank you in advance.
>
>  
>
> Thomas Shaw
>
> ------------------------------------------------------------------------
>
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>   


-- 
_________________________________________________________
Pierre GIRAUD
Géomaticien, Analyste

Camptocamp France SAS
Savoie Technolac, BP 352
73377 Le Bourget du Lac, Cedex 

Tel : 00 33 4 79 44 44 93
Mail : pierre.giraud at camptocamp.com
http://www.camptocamp.com  



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