As some readers will already know, the ODF document standard has support for including one or more RDF/XML files. I have made a few such files, and will grow that collection over time. The weekend hike document cites a few people, links some to a location and also cites a time and place. While one could just say "Dom Plein" or "11 am Wednesday" these purely text references are subjective and require a human to read them.
On the other hand, the location could have an exact bounding polygon or point with digital longitude and latitude information. A computer is all to happy to use that precise description to offer maps and "how to get there from here" type information. And the 11am is of course dubious because it doesn't link to a timezone, a human will know we are not talking UK time or the ACDT timezone. But that requires inference from the cited location and knowledge of which Plein that is, or rather, which timezone that Plein is in.
I did a little hacking to freshen up some of the RDF code in Calligra and bring back optional support for using Marble to show and edit location information. The below is the weekend hike example from the github above. James, Joyce, and Mark all have contact RDF associated, with Mark also giving his location. The "next weekend" at the end of the first paragraph has both a time and place associated. In the screenshot I've opened up the place to edit it. Rather simple to drag a map around and click OK than to know the digital coordinates right of the top of your head ;)
I was hacking on fixing the same bug as boemann on #calligra, which is strange for me as I normally don't overlap on things. It seems along the way setCanvas() was called again so I removed my explicit view passing stuff in the update I just git pushed. It looks like the docker was fixed correctly by somebody else in the end. My SPARQL updates should still help. It has been a while since I hacked on this codebase, and I have to thank the Calligra guys for being so welcoming and having such a fun contribution environment! I'm fortunate to be able to hack on two projects, Abiword and Calligra, which are both so welcoming :)