[gdal-dev] GDAL rejecting Winkel Tripel projection

[Even Rouault]

Le vendredi 22 octobre 2010 22:48:43, William Kyngesburye a écrit :
> So, why?  Is it because it has no defined inverse projection?  I think
> aitoff is another such, and it's not handled by GDAL either.

I don't know the reason. My guess is that perhaps beause nobody cared enough 
about that projection to add support for it ??

> 
> I see a +wktext option mentioned in ogr_srs_proj4.cpp:importFromProj4(),
> but it doesn't help.  I guess importFromProj4() looks at the projection
> and rejects the proj4 string before +wktext is helpful.

+wktext cannot help when OSR doesn't recognize the projection. It only helps 
to keep the extra options that OSR doesn't handle by itself.

> 
> If I could figure out a WKT definition, does GDAL restrict that?
> 
> Any other way I can get GDAL to use wintri?

You can write the WKT and add a EXTENSION['PROJ4','+proj=wintri ...'] node in 
it, so it is used when translating it into proj4.

> 
> On Oct 22, 2010, at 3:07 PM, Even Rouault wrote:
> > apparently, the OGRSpatialReference object has currently no support for
> > this projection.
> > 
> > Le vendredi 22 octobre 2010 21:50:59, William Kyngesburye a écrit :
> >> Using gdalwarp and ogr2ogr with:
> >> 
> >> -t_srs '+proj=wintri'
> >> 
> >> I get:
> >> 
> >> Translating source or target SRS failed:
> >> +proj=wintri
> >> 
> >> and:
> >> 
> >> Failed to process SRS definition: +proj=wintri
> >> 
> >> respectively.
> >> 
> >> Other proj-style SRS definitions work, but not wintri.  It works
> >> directly with the proj program.
> >> 
> >> Is GDAL blocking use of wintri, or not configured to use it?
> >> 
> >> -----
> >> William Kyngesburye <kyngchaos*at*kyngchaos*dot*com>
> >> http://www.kyngchaos.com/
> >> 
> >> All generalizations are dangerous, even this one.
> >> 
> >> 
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> 
> -----
> William Kyngesburye <kyngchaos*at*kyngchaos*dot*com>
> http://www.kyngchaos.com/
> 
> "Mon Dieu! but they are all alike.  Cheating, murdering, lying, fighting,
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> 
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