I was going to try to stick to OpenStreetMap and other existing mapping applications like TangoGPS, a neat little smartphone app for downloading OpenStreetMap tiles that also runs on the desktop -- but really, there still isn't any mapping app that works well enough for exploring maps when you have no net connection.
In particular, uploading my GPS track logs after a day of mapping, I discovered that Tango really wasn't a good way of exploring them, and I already know Merkaartor, nice as it is for entering new OSM data, isn't very good at working offline. There I was, with PyTopo and a boring hotel room; I couldn't stop myself from tweaking a bit.
Adding tracklogs was gratifyingly easy. But other aspects of the code bother me, and when I started looking at what I might need to do to display those Tango/OSM tiles ... well, I've known for a while that some day I'd need to refactor PyTopo's code, and now was the time.
Surprisingly, I completed most of the refactoring on the trip. But even after the refactoring, displaying those OSM tiles turned out to be a lot harder than I'd hoped, because I couldn't find any reliable way of mapping a tile name to the coordinates of that tile. I haven't found any documentation on that anywhere, and Tango and several other programs all do it differently and get slightly different coordinates. That one problem was to occupy my spare time for weeks after I got home, and I still don't have it solved.
But meanwhile, the rest of the refactoring was done, nice features like track logs were working, and I've had to move on to other projects. I am going to finish the OSM tile MapCollection class, but why hold up a release with a lot of useful changes just for that?
So here's PyTopo 0.8, and the couple of known problems with the new features will have to wait for 0.9.
[ 20:49 Jun 20, 2009 More programming | permalink to this entry | ]