[Proj] Problem with merc projection

Antonio Volpicelli volpicelli at oato.inaf.it
Sun Dec 30 07:14:52 PST 2007


Yes Thanks Oscar.
PROJ and cs2cs works fine.
I am mapping my images ( on mapserver) using it as WMS on Google Sky and 
the images match exactly.

I am trying to modify the merc.js code.

Thanks again

Antonio

Oscar van Vlijmen ha scritto:
>> From: Antonio Volpicelli
>> Date: Wed, 26 Dec 2007 22:27:45 +0100
>> Subject: [Proj] Problem with merc projection
>>     
>
>   
>> I am using the Mike Adair proj4js and merc.js code .
>> The trasformation using cs2cs gives me different result if I use the
>> Mike code.
>> When I transform lon/lat to X/Y the Mike code give me a latitude lower
>> then the cs2cs of about 0.200 degrees.
>>     
>>> cs2cs +proj=latlong +to +proj=merc
>>>       
>> 10.6846908 41.26904150
>> 1189414.34      5023915.99 0.00
>> with the Mike code
>> 1189414.34   5052106.58
>>     
>
> PROJ (and CS2CS) works as expected.
> PROJ does an ellipsoidal Mercator projection with in this case default
> parameters:
> lon0=0; x0=0; y0=0; k0=1.0; WGS84 ellipsoid.
> Apparently the 'Mike' code does a spherical Mercator, taking the semi-major
> WGS84 axis as the radius.
>
>
> _______________________________________________
> Proj mailing list
> Proj at lists.maptools.org
> http://lists.maptools.org/mailman/listinfo/proj
>   




More information about the Proj mailing list