[gdal-dev] GPKG Driver

[Pepijn Van Eeckhoudt]

Hi Paul,

Great news that you’re planning on working on this. I had intended to do this and had discussed this a bit with Even already, but I haven’t had time to do any real work yet. Too busy getting geopackage support ready in Luciad’s own products first.

On 28 Oct 2013, at 20:05, Paul Ramsey <pramsey at cleverelephant.ca> wrote:

> I think most of the storage/retrieval stuff is going to be from
> scratch. The more operational stuff, like rtree index bindings and so
> on, could/should lean on the luciad code (though I don't actually see
> those mentioned). I'm loath to add a build dependency, but perhaps
> copying the tree into the driver would be acceptable? (Except it's a
> cmake project, and gdal is not, hm)

Even,

I've had a quick look at the OGR code in the meantime and at first glance it doesn’t seem to make much sense to use libgpkg for ogr/gdal integration. The bulk of the code in libgpkg is similar to what CPL provides in ogr. It wouldn’t make sense imo to duplicate that type of code. The actual geopackage specific code consists of WKT, WKB and GPB header (un)marshalling code, table creation statements and GEOS integration. I’m sure you guys already have code for all that lying around somewhere :)

Regarding the rtree implementation this is not part of libgpkg itself. We’re using the rtree implementation that ships with sqlite (http://www.sqlite.org/cgi/src/dir?ci=10f125f5da55eca1&name=ext/rtree). libgpkg only contains code to create the rtree tables and set up the necessary triggers. The SQL code for that is all part of the geopackage spec, so I don’t think there’s any need to use libgpkg for that either.

Regards,

Pepijn