[postgis-users] Projection help (please)

[Frank Warmerdam]

Chapman, Martin wrote:
> Brent,
> 
> #include "ogrsf_frmts.h"
> #include "gdal_priv.h"
> 
> char* pszWks = "the text from the .prj file goes here";
> OGRSpatialReference spatialReference(pszWks);
> OGRErr err = spatialReference.morphToESRI(); // needed if the using an
> esri .prj file
> if (err != OGRERR_NONE) throw (char*) CPLGetLastErrorMsg();
> 
> char* pszProj4 = NULL;
> spatialReference.exportToProj4(&pszProj4);

Folks,

I think you should be using "morphFromESRI()" not "morphToESRI()".  The
FromESRI() version converts ESRI style WKT into OGR style WKT.   It
may not matter much for a given WKT value of course since they are pretty
similar.

Something similar can also be implemented in Python for the C++ adverse.

> -- there you go
> -- p.s I think the pszProj4 variable should be freed with
> CPLFree(pszProj4); -- not sure though, see the on-line docs for that

Yes, it should be freed with CPLFree(), though free() would actually
work fine *most* of the time.

Best regards,

-- 
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I set the clouds in motion - turn up   | Frank Warmerdam, warmerdam at pobox.com
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