[Xastir] Script to cache some maps

[Hal Mueller]

In the FOSS4G (free/opensource software for geospatial) world, there are two leading map renderers, MapServer and Mapnik. Both of those can be configure to render and serve tiles conforming to the spherical Mercator tiling scheme used by Google, Apple, Mapquest, OSM, and others. Both packages are fast, and allow you to configure the layers and rendering styles quite precisely. They also allow you to pull in source rasters (or vectors) from multiple sources, and combine them. Server-side tile caching is available for both MapServer and Mapnik.

The point of using a tile server is to leverage the amount of work already devoted to making beautiful maps, rendered quickly, and to serve them efficiently. It also keeps APRS (and other) clients from having to get into the cartography business.

From the points made in this discussion, it sounds like Xastir can use those hierarchical tile sets. I don’t see any such claim at http://xastir.org/index.php/Xastir_Maps#Raster_Maps or http://xastir.org/index.php/HowTo:MAPS, though.

An SQLite based format, mbtiles, can store a tile tree compactly. That would let you generate a file for a local area, and then, say, distribute that .mbtiles file to all SAR or Emcomm team members. That format is described briefly at https://www.mapbox.com/help/an-open-platform/#storing-tiles. However, Xastir does not (AFAIK) read mbtiles.

Mapbox offers pay-as-you-go subscriptions to their own tile servers, which have up-to-date raster and vector data. So here’s a legitimate way to prefetch all the maps you need. Their older tool, Tilemill, had export capability to raster mbtiles. Their current tool, Mapbox Studio, exports only vector-based mbtiles. To convert to rasters, you can follow the procedure outline at http://www.azavea.com/blogs/labs/2015/05/converting-mapbox-studio-vector-tiles-to-rasters/ (includes link to a vector->raster mbtiles converter, https://github.com/lliss/tile-converter).

Can Xastir be pointed to a tree of hierarchical tiles? Or even better, can it read mbtiles (raster or vector)?

Hal
N3YX