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I'm trying to add tpers projection as a custom projection in QGIS 2.10.1

In the Custom crs dialog I'm adding the proj.4 text:

+proj=tpers +h=500000000 +lat_0=19 +lon_0=99 +x_0=0 +y_0=0 +a=6371000 +b=6371000 +units=m

And when I test with some North and East values, QGIS calculates some output coordinates. The thing is that, when I click done, QGIS complains that The proj4 definition of 'tpers' is not valid.

I've read this answer but I think that the tpers definition must be outdated since it produces error when I try to test it in the custom crs dialog.

The proj.4 string I'm using comes from here

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    There is a difference in the Proj.4 and MapProjectionViewer.. proj says you need tilt and azi but the viewer has neither (+proj=tpers +h=500000000 +lat_0=0 +lon_0=0 +x_0=0 +y_0=0 +a=6371000 +b=6371000 +units=m), the tilt (+tilt=%f) and azimuth (+azi=%f) parameters are missing.
    – Michael Stimson
    Commented Sep 4, 2015 at 0:32
  • @MichaelMiles-Stimson Basically, you are right, but it does not solve the error. Even ogr2ogr fails with ogr2ogr -t_srs "+proj=tpers +lat_0=10 +lon_0=10 +h=10000 +tilt=10 +azi=10" tilt.shp test.shp. And gdalsrsinfo does not like it either.
    – AndreJ
    Commented Sep 4, 2015 at 5:18
  • Strangely, cs2cs +init=epsg:4326 +to +proj=tpers +h=500000.000 +lat_0=19 +lon_0=19 +x_0=0 +y_0=0 +azi=10 +tilt=10 +R=6371000 +units=m wgs.txt >tilt.txt works.
    – AndreJ
    Commented Sep 4, 2015 at 6:09
  • @MichaelMiles-Stimson I also noticed the mismatch but oddly enough, QGIS seemed to like better the MapProjectionViewer version
    – plablo09
    Commented Sep 4, 2015 at 14:29

1 Answer 1

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According to this ticket: https://trac.osgeo.org/gdal/ticket/3404 the tilted perspective projection is not added to GDAL (but is in Proj.4).

That is why GDAL/OGR based programmes like ogr2ogr, gdalsrsinfo and QGIS can not understand it, while cs2cs (based on pure Proj.4) and the testing suite of QGIS can work with it.

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