[gdal-dev] Support for measures

[Even Rouault]

> 
> BTW, where can I find a comprehensive list of the wkb types? There is an
> old ISO SQL/MM Part 3 pdf in the web but it is old and seems to be
> incorrect too. libspatialite has a header file that has many but not all
> that ogr_core.h has.

I see I had linked
https://github.com/postgis/postgis/blob/svn-trunk/doc/bnf-wkb.txt
into
https://trac.osgeo.org/gdal/wiki/rfc49_curve_geometries

Also listed in http://portal.opengeospatial.org/files/?artifact_id=25355 (​
OpenGIS Simple Feature Access Part 1 : Common Architecture,v 1.2.1) , pages 
63-64.

Regarding your addition "ICreateLayer, which all(?) drivers implement,

--> no, there are many read-only drivers

" have geometry type as an argument. The method should call CPLError() with 
CPLE_NotSupported and return NULL if the driver does not support measures. 
Similarly for ICreateFeature and ISetFeature. ",

my point with adding the new capabilities was that drivers that wouldn't 
advertize the M capabilities would never see a M or ZM geometry / geometry 
type passed. See what the (non-virtual) methods 
OGRLayer::SetFeature(),CreateFeature() and GDALDataset::CreateLayer() do for 
curve geometries. Similar things could be done for M.


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