[gdal-dev] Compound CRS in shapefile

[Even Rouault]

Javier,

> When I create a 3D shapefile with GDAL, and I provide as SpatialReference a
> compound CRS, it generates the prj file with the COMPD_CS syntax. Ok so far.

Always be specific: show the content of the .prj

> However, when I open the shapefile in QGIS, it does not recognize the CRS
> at all (neither the horizontal part)

What do you call "recognize" exactly: it doesn't find any CRS information, or 
doesn't retrieve a EPSG code (retrieving a EPSG code from ESRI WKT is deeply 
dark magic so doesn't always work) ?

> Is that intentional? QGIS is using GDAL to deal with shapefiles, afaik.

Probably for QGIS mailing list or tracker then.

I've tested the following:

ogr2ogr out.shp poly.shp -a_srs EPSG:7405

ogrinfo out.shp reports correctly a compoundCRS.

Opening that in QGIS + GDAL + PROJ master shows EPSG:27700 (the horizontal 
part). Looking at QGIS QgsCoordinateReferenceSystem class, it only keeps the 
horizontal part of a CompoundCRS. I guess mostly for compatibility reasons 
with the rest of the code base.

Even

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