[gdal-dev] Importing OSM: closed ways being skipped

[Richard Marsden]

Even,

Thanks  - I'll have a look at ds.GetNextFeature().  I'll note that the
sample (C++) code on the interleaved reading section, is where I got
the double loop that looped over layers, and then features within that
layer. This led me astray because it loops over the layers in index
order - doing this results in the closed ways being skipped.

Richard

On Fri, Sep 27, 2019 at 4:28 PM Even Rouault <even.rouault at spatialys.com> wrote:
>
> > The amended code looks like this:
> >
> >         ds = gdal.OpenEx(input_pbfname, gdal.OF_VECTOR)
> >         nly = ds.GetLayerCount()
> >         ds.ResetReading()
> >         for ily in (0,1,2,4,3):
> >             layer = ds.GetLayerByIndex(ily)
> >             layer.ResetReading()
> >             feat = layer.GetNextFeature()
> >             while feat is not None:
> >                  # do stuff with feat
>
> This is not the proper way of doing layer interleaved reading. It might work
> by chance on your particular dataset, but not in the general case. See
> https://gdal.org/drivers/vector/osm.html#interleaved-reading
>
> With recent GDAL versions, you might also use ds.GetNextFeature()
>
> See https://github.com/OSGeo/gdal/blob/master/autotest/ogr/ogr_osm.py#L702
>
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