[weekly report] week 5: Local map rendering in Libchamplain

[Simon Wenner <simon wenner gmail com>]

Hi,

The rendering of local files is now implemented. If you want to try it,
run the new demo: 'demos/local-rendering'. The Memphis map source
supports changing the style/rules and the data source while rendering
tiles. The ability to redraw all visible tiles required changes in some
main classes of libchamplain (i.e. ChamplainView). If no rules or no
data is provided the data source creates empty (black) tiles. I'm not
sure if that's a good behavior. Should it draw 'error-tiles' instead?

During the development of the new map source I realized that switching
between sources with different tile sizes causes a shift of the view and
wrong tile numbers get loaded. Until now all sources used a tile size of
256px. Maybe that's an implicit assumption somewhere deep under the
hood. I searched but have not found yet the cause of this bug.

This week I will create the network-map-data-source. It will download
the map data from the OSM-API server and pass it to the renderer. The
progress of this milestone will depend on the weather conditions in Gran
Canaria ;-)

I will stay in Gran Canaria from the 1st to 11th of July. I hope to see
you all at the GCDS!

Simon

git shortlog
      Add ChamplainLocalMapDataSource class
      Add property enum, remove assumption about zoom levels
      Libmemphis: Sync to rev. 121 (renderer constructor and dispose bug
      Use MapSourceDesc in memphis_map_source_new_full, fix initialisati
      Add ChamplainMemphisMapSource to the factory
      Complete dispose functions, use more consistent names
      Add Memphis debug flag
      Add map-data-source property
      wait until every thread has finished (potential leak)
      The uri_format field can be abused to set an initial data path for
      launcher-gtk: set spin button to proper zoom level on startup
      Add local-rendering demo
      Add small data sets of Schaffhausen and Las Palmas for testing/pre
      Add default-rules.xml
      Add high-contrast rules, add zoom-to-data button
      Add a RWLock to protect the state of the MemphisRenderer
      Emit a signal if MapDataSource has changed
      Demo: Do not reload the map source if only the map data changes
      Silence the memphis parsing debug output
      Add signal 'reload-tiles' to ChamplainMapSource, if emitted all vi
      fix callback structure of the 'map-data-changed' signal
      Libmemphis: Sync to rev. 123 (use g_critical, const paths)
      Make path parameters constant