desruisseaux commented on PR #240: URL: https://github.com/apache/parquet-format/pull/240#issuecomment-2258139008
> In GeoParquet (and GeoPackage), there is language that makes it explicit that the first axis is always an easting or longitude even in the case where the authority does not define it in this way. GeoPackage itself replicated the GeoTIFF precedent. Those two standards were originally developed outside OGC, and we have difficulties in conciliating the community practice with being unambiguous. A language mandating (_easting_, _northing_) order does not work at the North pole where all directions are oriented toward south. It is ambiguous with map projections having axes such as (_west_, _north_) or (_east_, _south_): should we also revert the sign of coordinate values? And it does not work at all with CRS having _aft_, _port_, _starboard_, _clockwise_, _counter-clockwise_, _toward_, _away-from_ directions such as vehicles (all those directions are part of ISO 19111 standard). The [ISO 19107:2019 — Spatial schema](https://www.iso.org/standard/66175.html) standard (the abstract model for geometries from which Simple Feature is a simplified subset) addresses this problem with a `Permutation` class which contains a `outOrder` field. Can we do something along the line of that standard in GeoParquet? When SRID `EPSG:4326` is used, a "Permutation" field should contain the {1, 0} array of integers (or {2, 1} if we start counting at 1) for explicitly requesting a change of axis order from (_latitude_, _longitude_) to (_longitude_, _latitude_). Reference: ISO 19107:2019 §6.2.8.6 -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected] --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
