[gdal-dev] Open source vector geoprocessing libraries?

[Jan Hartmann]

On 17-1-2010 22:02, Mateusz Loskot wrote:
> Does that mean that I can use ogrinfo on a gzipped archive, like
>> gdalinfo (http://trac.osgeo.org/gdal/wiki/UserDocs/ReadInZip)?
>>      
>
> Yes, it does but...as long as OGR driver performs filesystem
> operations using VSI*L API. The problem is that only few of them use VSI*L.
>
> As an example, I just updated OGR GeoJSON driver to use VSI*L API:
>
> http://trac.osgeo.org/gdal/changeset/18573
>
> As you can see, it is not a complex task, but may be time consuming and
> tedious, and requires quite a lot of testing.
>
> After these changes are applied, it is possible to (un)gzip GeoJSON
> datasets:
>
> 1) Translate Shapefile to GeoJSON file compressed using GZip:
>
> $ ogr2ogr -f GeoJSON /vsigzip/./points.geojson.gz points.shp
>
> 2) Read GZip compressed GeoJSON dataset:
>
> $ ogrinfo /vsigzip/./points.geojson.gz
>
> $ ogrinfo /vsigzip/./points.geojson.gz OGRGeoJSON
>
>    

>> It would be a nice archive functionality.
>>      
> Yes, indeed.
>
> The work requires to step in to each OGR driver directory,
> grep .cpp files for VSI verify what VSI API is used.driver:
>
> For example, OGR Shapefile driver would, in theory, need to get
> updated VSI calls in about 50 places:
>
> $ grep VSI *.cpp | wc -ls
> 47
>
> I'm quite sure volunteers would be appreciated.
>
>    

Thanks Mateusz. I am going to look at GeoJSON as an ASCII data archiving 
format, as long as long as a full-fledged GML driver isn't available I 
have always liked JSON more then XML.

Jan