[OSM-dev] [GSoC] Data Tile Service

[Michael Daines]

Hello,

Here are some updates for the GSoC Data Tile Service project.

The repository for the tile rendering script is available here:

  https://github.com/mdaines/render-data-tile

The script will render JSON tiles using data imported to PostgreSQL/PostGIS with osm2pgsql. It can render individual tiles or a list of indices. There is also a web-based debugging tool in the debug directory which renders tiles on demand and displays them using HTML5 canvas and Leaflet.

I have been running the render and debug scripts with the geofabrik extract of the state of California. I have also been experimenting with rendering tiles for that entire area. Here is an example tile:

  http://temporary.mdaines.com/gsoc-2012/15-5238-12699.js

A note on file sizes: this particular tile is about 12K, and 3.2K gzipped. The corresponding Mapnik image is 14K (about the same size gzipped).

I have also created a page on the wiki for documenting the data tile format produced by the script:

  http://wiki.openstreetmap.org/wiki/Google_Summer_of_Code/2012/Data_Tile_Service/Tile_Format

The format is basically a subset of GeoJSON with the addition of the Kothic data tile format's "granularity" property. This allows coordinates to be expressed as integers relative to the tile's position.

This coming week I will be working on documentation, geometry simplification and filtering, and on making a set of tiles for the data I have been working with.


-- Michael