This is the slides presented at Open Seminar Series in Institute of Information Science, Academia Sinica. The seminar information information was posted at
http://registrano.com/events/b05266
95. Backend database: PostgreSQL
• OSM doesn’t use geometry type of PostgreSQL
and geospatial functions of PostGIS.
• OSM API v0.6 is used for the main central OSM
DB running on servers.
• http://wiki.openstreetmap.org/wiki/API_v0.6
• Osmosis is used to populate a more general
PostgreSQL/PostGIS DB from Planet.osm dump
file.
• http://wiki.openstreetmap.org/wiki/Osmosis
Monday, July 15, 2013
97. Mapnik
www.mapnik.org
• OSM uses Mapnik to render 256 X
256 pixels tiles
• osm2pgsql is used to convert OSM
data to postgreSQL for Mapnik
rendering
• Map sytles are controlled by
stylesheet (XML) files.
• Useful tutorial! https://github.com/
mapnik/mapnik/wiki/MapnikTutorials
Monday, July 15, 2013
98. Mod tile
• Mod tile is a system to serve tiles, for
example to use within a slippy map.
• The implement of Mod file is split into two
ports
• mod_tile is a custom Apache module
which is responsible for serving tiles and
requests the rendering of tiles
• renderd - A rendering daemon which calls
mapnik and writes the map tiles to the
filesystem
Monday, July 15, 2013
99. tile@home
• Tiles@home (short:T@H or tah) is a distributed
program to render Osmarender maps.
• T@H has a server software,Tahngo (generation
2), running at the Tiles@home website, which get
requests to render tiles from updated mapdata.
Monday, July 15, 2013
101. Slippy map
• The slippy is an Ajax component. JavaScript runs in the
browser, which dynamically requests tiles from the
server in the background (without reloading web page)
to give a smooth map browsing experiences.
• The implementation of slippy map is mostly provided
by OpenLayers
• The tiles rendering usually comes from two resources
• Mapnik tile rendering
• Osmrender (tiles@home) tile rendering
See details http://wiki.openstreetmap.org/wiki/Develop
Monday, July 15, 2013