[gdal-dev] Failure to convert to Airy

[Joaquim Manuel Freire Luís]

Thanks,

This comes from our GMT tests and used to work before the GDAL3+PROJ6 combo. And funny that it also half works when I run it from Julia. But not from GMT.

|>-----Original Message-----
|>From: Even Rouault <even.rouault at spatialys.com>
|>Sent: Monday, June 17, 2019 5:37 PM
|>To: gdal-dev at lists.osgeo.org
|>Cc: Joaquim Manuel Freire Luís <jluis at ualg.pt>
|>Subject: Re: [gdal-dev] Failure to convert to Airy
|>
|>On lundi 17 juin 2019 16:08:36 CEST Joaquim Manuel Freire Luís wrote:
|>> Even
|>>
|>> I'm seeing this failure with the airy conversion
|>>
|>> echo 4.897 52.371 | gdaltransform -s_srs +proj=longlat -t_srs
|>> +proj=airy
|>>
|>> ERROR 1: PROJ: proj_create: Error -50: malformed pipeline ERROR 6:
|>> Cannot find coordinate operations from
|>> `PROJCRS["unknown",BASEGEOGCRS["unknown",DATUM["World Geodetic
|>System
|>> 1984",ELLIPSOID["WGS
|>>
|>84",6378137,298.257223563,LENGTHUNIT["metre",1]],ID["EPSG",6326]],PRIM
|>> EM["G
|>>
|>reenwich",0,ANGLEUNIT["degree",0.0174532925199433],ID["EPSG",8901]]],C
|>> ONVERS
|>> ION["unknown",METHOD["PROJ
|>> airy"]],CS[Cartesian,2],AXIS["(E)",east,ORDER[1],LENGTHUNIT["metre",1,
|>> ID["E
|>> PSG",9001]]],AXIS["(N)",north,ORDER[2],LENGTHUNIT["metre",1,ID["EPSG",
|>> 9001]] ]]' to `GEOGCRS["unknown",DATUM["World Geodetic System
|>> 1984",ELLIPSOID["WGS
|>>
|>84",6378137,298.257223563,LENGTHUNIT["metre",1]],ID["EPSG",6326]],PRIM
|>> EM["G
|>>
|>reenwich",0,ANGLEUNIT["degree",0.0174532925199433],ID["EPSG",8901]],CS
|>> [ellip
|>> soidal,2],AXIS["longitude",east,ORDER[1],ANGLEUNIT["degree",0.01745329
|>> 251994
|>> 33,ID["EPSG",9122]]],AXIS["latitude",north,ORDER[2],ANGLEUNIT["degree"
|>> ,0.017 4532925199433,ID["EPSG",9122]]]]' 328249.00331295
|>> 4987937.10144727 0
|>>
|>
|>Actually, this half works: you get the correct result, but with an error message.
|>This is because the airy projection has no code in PROJ to compute its reverse
|>operation, and gdaltransform logic instanciates both forward and reverse
|>transformers.
|>Error message, not relevant for your use case, shut off by
|>https://github.com/OSGeo/gdal/commit/d1b68ad5f3adc3ec8f66a4a6dac5d765
|>5670a08c
|>(which also fixes a real crashing bug when trying to use the null reverse
|>method)
|>
|>Even
|>
|>--
|>Spatialys - Geospatial professional services http://www.spatialys.com