[gdal-dev] GDAL 3.3.0beta1 available

[Greg Troxel]

Even Rouault <even.rouault at spatialys.com> writes:

> - http://download.osgeo.org/gdal/3.3.0/gdal-3.3.0beta1.tar.gz

The tl;dr is:

  - I'm seeing bad transforms NAD83/ITRF with 3.3.0beta1 but I do not
    have any basis to blame 3.3.0 because a lot of other things are in
    flux.

  - If you are using 3.3.0beta1 and transforms I suggest looking at your
    output data.



I have noticed a problem but I have little idea where it is.  I will be
looking into it myself but I wanted to mention it so that others could
be on the lookout.

Besides updating to gdal, I'm doing a general software freshening and
rebuilding lots of things, but aside from the gdal beta my geo packages
haven't changed versions.  I have proj 6.3.2 with installed grids, which
was just rebuilt.

The background is that I'm mostly working in EPSG:6319 which is
NAD83(2011).

I transform to EPSG:7912 which is ITRF2014 to display the data on
leaflet webmaps (as a proxy for WGS84 to avoid null transforms).

I noticed that my points on the webmap were very far off, displaced very
roughly 35m ESE.  I then put an NAD83 version in the webspace, and that
made things look ok (with the ~1 meter error from treating NAD83 and
ITRF2014 as equal, surely).

I'm extracting things from a geopackage in 6319 like

    ogr2ogr -f GeoJSON -t_srs "EPSG:7912" -s_srs "EPSG:6319" FOO/issues.geojson foo.gpkg issues
    ogr2ogr -f GeoJSON -t_srs "EPSG:6319" -s_srs "EPSG:6319" FOO/issues-nad83.geojson foo.gpkg issues

which has previously been fine.  I'm definitely getting very large
offsets from two files extracted seconds apart from the very same
geopackage.

So this is not a request for help, but if you are using ogr2ogr to
transform datums, and you are using gdal 3.3.0beta1 especially with proj
6, I'd suggest a quick look at your output data to see if it seems ok.

I will be retesting after all the software rebuilds are done, and
rolling back to released gdal.  (Yes, I know proj 6.3 is old and that I
should update.)

Thanks,
Greg
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