Calligra/Ideas/Open Street Map Integration

From KDE Community Wiki

Talked with Jörg Ostertag <openstreetmap At ostertag.name> about open street map.

The idea I had is that KOffice shows a map and allows people to navigate and after doing so we will downlooad data from the open streetmap server to include in the KOffice document in a vector format.

OSM has a couple of ways that their data is used. It has a live data server that has a webserver service API that allows you to fetch the internal data format. (.osm IIRC) Second there is a server that uses a weekly snapshot with pre-processed data (postgis) that is inserted into a database and which is used for the website.

The following setup has been suggested as a first version;

  • The user using KOffice selects a rectangle somewhere on earth that he wants the map data for. (i.e. use Marble)
  • The KOffice plugin connects to the live data servers webservice to request the data for that area. As the webservice currently has a size limit of 0.3 degrees (some 48km) we might want to do several requests.
  • We get an xslt from OSM that we use to convert the data fetched in the previous step into svg.

We can then simply load that svg into a new vector shape.

Future feature requests

  1. provide the xslt via a webservice as well. (preferably allowing a 'HEAD' like request to check if we are up to data).
  2. Provide a new service based on a filtered database of the data so the non-visual things are not sent to the client.
  3. Provide a way to remove detail on the OSM server based on a webservice property.
  4. Check and/or fix that the xslt is capable of setting a DPI which is used for the size of the fonts used in the svg.