Ok.

I've checked the behaviour of Python library rasterio when we feed it a WKT
2 using a datum ensemble, and it looks like it's fine.
So no objection on my side.

Tested script, for reference:

from rasterio.crs import CRS, WktVersion
>
> ogc_crs84_wkt2 = """
> GEOGCRS["WGS 84 (CRS84)",
>     ENSEMBLE["World Geodetic System 1984 ensemble",
>         MEMBER["World Geodetic System 1984 (Transit)"],
>         MEMBER["World Geodetic System 1984 (G730)"],
>         MEMBER["World Geodetic System 1984 (G873)"],
>         MEMBER["World Geodetic System 1984 (G1150)"],
>         MEMBER["World Geodetic System 1984 (G1674)"],
>         MEMBER["World Geodetic System 1984 (G1762)"],
>         MEMBER["World Geodetic System 1984 (G2139)"],
>         ELLIPSOID["WGS 84",6378137,298.257223563,
>             LENGTHUNIT["metre",1]],
>         ENSEMBLEACCURACY[2.0]],
>     PRIMEM["Greenwich",0,
>         ANGLEUNIT["degree",0.0174532925199433]],
>     CS[ellipsoidal,2],
>         AXIS["geodetic longitude (Lon)",east,
>             ORDER[1],
>             ANGLEUNIT["degree",0.0174532925199433]],
>         AXIS["geodetic latitude (Lat)",north,
>             ORDER[2],
>             ANGLEUNIT["degree",0.0174532925199433]],
>     USAGE[
>         SCOPE["Not known."],
>         AREA["World."],
>         BBOX[-180,-90,180,90]],
>     ID["OGC","CRS84"]]
> """
>
> decoded_crs = CRS.from_wkt(ogc_crs84_wkt2)
> assert decoded_crs.is_valid
> assert decoded_crs.is_geographic
>
> print(decoded_crs.to_wkt(version=WktVersion.WKT2_2019))
>
>
Regards,

Le jeu. 25 juil. 2024 à 09:49, Martin Desruisseaux <
[email protected]> a écrit :

> Le 2024-07-25 à 07 h 50, Alexis Manin a écrit :
> >
> > The only question that comes to mind is: would it affect CRS WKT
> > serialization in any way ? For interoperability with third-party
> > systems, WKT is often used. If the EPSG upgrade do not cause
> > incompatible/breaking changes in this regard, then dropping old EPSG
> > version might be a problem.
> >
> It does in some way. In EPSG:4326, the datum is no longer a datum but a
> datum ensemble. It means that in WKT 2, the DATUM["WGS 84", ...] element
> become ENSEMBLE["WGS 84", more stuff]. The latter did not existed in ISO
> 19162:2015 and requires ISO 19162:2019. Therefore, the WKT become
> unparseable for applications that haven't upgraded to ISO 19162:2019
> yet. It includes Apache SIS itself (the upgrade is in progress, in
> parallel with the EPSG upgrade).
>
> However, the WKT 2 strings that I see circulating in other projects and
> in OGC testbeds are already ISO 19162:2019 strings. I have not seen an
> "old" 19162:2015 string for a long time. So it seems that most of the
> market already moved there.
>
>      Martin
>
>

-- 
Alexis Manin,
Développeur JAVA/JEE.
Geomatys.

Reply via email to