[postgis-tickets] [PostGIS] #5262: Add support of Undefined Cartesian SRS (-1)

[PostGIS]

#5262: Add support of Undefined Cartesian SRS (-1)
--------------------------+---------------------------
  Reporter:  lbartoletti  |      Owner:  pramsey
      Type:  enhancement  |     Status:  new
  Priority:  medium       |  Milestone:  PostGIS 3.3.2
 Component:  postgis      |    Version:  3.3.x
Resolution:               |   Keywords:
--------------------------+---------------------------
Description changed by lbartoletti:

Old description:

> Postgis uses 0 as undefined SRS. But you can have an undefined geographic
> srs (0) and an undefined cartesian srs (-1). This is what is proposed in
> the GeoPackage table[1][2] (and I think it comes from an OGC standard I
> forgot).
>
> If, with ogr2ogr, I convert my "local" cartesian table to postgis, it
> will be an undefined srs (0, since there is a constraint CHECK (srid > 0
> AND srid <= 998999) and SRID_UNKOWN is 0[3]).
>
> Can cause trouble if you have two undefined tables, one geographic and
> the other one cartesian.
>

> [1] https://gdal.org/drivers/vector/gpkg.html#coordinate-reference-
> systems
> [2] http://www.geopackage.org/guidance/getting-
> started.html#gpkg_spatial_ref_sys
> [3]
> https://github.com/postgis/postgis/blob/3e38e0b83b98925122bb22dff958a7a603ee4a42/liblwgeom/liblwgeom.h.in#L210

New description:

 Postgis uses 0 as undefined SRS. But you can have an undefined geographic
 srs (0) and an undefined cartesian srs (-1). This is what is proposed in
 the GeoPackage table[1][2] (and I think it comes from an OGC standard I
 forgot).

 If, with ogr2ogr, I convert my "local" cartesian table to postgis, it will
 be an undefined srs (0, since there is a constraint CHECK (srid > 0 AND
 srid <= 998999) and SRID_UNKOWN is 0[3]).

 Can cause trouble if you have two undefined tables, one geographic and the
 other one cartesian.


 [1] https://gdal.org/drivers/vector/gpkg.html#coordinate-reference-systems

 [2] http://www.geopackage.org/guidance/getting-
 started.html#gpkg_spatial_ref_sys

 [3]
 https://github.com/postgis/postgis/blob/3e38e0b83b98925122bb22dff958a7a603ee4a42/liblwgeom/liblwgeom.h.in#L210

--
-- 
Ticket URL: <https://trac.osgeo.org/postgis/ticket/5262#comment:1>
PostGIS <http://trac.osgeo.org/postgis/>
The PostGIS Trac is used for bug, enhancement & task tracking, a user and developer wiki, and a view into the subversion code repository of PostGIS project.