Hi Michael, > > I have read that GDAL can now update GeoJSON since version 2.1.0. See [1] > > If I build QGIS with GDAL 2.1, would I be able to edit the GeoJSON as I can > for Shapefiles ?
Yes, that was developed mostly for the QGIS use case and has been tested with it. You have full editing capabilities : adding, deleting, modifying features, adding, deleting fields. > > Another GeoJSON related question. Any idea on the relevance of adding the > ability to create a spatial index file *.qix for GeoJSON layers in order to > improve rendering speed ? The OGR GeoJSON driver proceeds into the ingestion of the full file into memory, which can be a limitation when dealing with huge files ( the json-c lib might typically consume an amount of memory more than 10 times the size of the geojson file). For a in-memory layer like the one used underneath by the GeoJSON driver, the spatial filtering done by OGR uses a basic BBOX filter while iterating over the features (the BBOX isn't stored into the geometry object but recomputed each time it is needed). This could potentially benefit from a in-memory spatial index, but I'd expect that to be only useful for large geojson files (let's say > 100 MB), i.e. the ones that the driver would currently have issues to deal with. A more "streaming-like" approach for the driver not proceeding to full ingestion of features could be desirable to remove that limitation, but that's more involved. A possibility could be to have a "at-hand" parser to delimitate JSon "Feature" objects and use only json-c to parse each feature. But GeoJSON is certainly not the more appropriate file format to deal with huge datasets... Cheers, Even -- Spatialys - Geospatial professional services http://www.spatialys.com _______________________________________________ Qgis-developer mailing list Qgis-developer@lists.osgeo.org List info: http://lists.osgeo.org/mailman/listinfo/qgis-developer Unsubscribe: http://lists.osgeo.org/mailman/listinfo/qgis-developer