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mappingopenstreetmapmapnik

OSM, TileCache, and Mapnik

I have been trying for two and a half weeks so far to get a local copy of OpenStreetMap running on a server. I have downloaded the planet file and imported it into a PostGIS database called 'osm'. I have used OSM Mapnik tools to generate an XML stylesheet for Mapnik to use. I have used TileLite to prove that Mapnik can render OSM tiles from the database. The tiles even look the way that I want them to look.

My problem now is that I cannot get TileCache to work with Mapnik. I have a MapServer instance installed that I am using to serve Shapefiles. This works with TileCache. The default 'basic' layer in the TileCache configuration file works as well. Please help with my OSM layer:

[osm]
type=Mapnik
mapfile=/var/maps/bin/mapnik/osm.xml
spherical_mercator=true
bbox=-16697000,8610000,-16667000,8640000
maxResolution=156543.0339/4
levels=18
srs=EPSG:900913

I have read every last blog post, forum post, and tutorial I can find. Any help would be appreciated. I suspect I have either missed something or I am doing something stupid.

Solution

  • Nik,

    I can understand the potential difficulties here and that you've tried a number of things. You did not say what exact problems you ran into however, so I'll guess that this is your problem:

    • You are using OpenLayers to test that the tiles are being produced correctly, but things don't line up when you connect to the tiles generated by TileCache.

    That it? If not, please provide a bit more detail.

    If that is the problem then likely what you need to do is to make sure to use a "TMS" layer type in OpenLayers and to match that with your TileCache.cfg layer params. "TMS" is very similar to the OSM tile scheme except that the y value is flipped.

    Anyway, something like this should work:

    tilecache.cfg

    [osm]
type=Mapnik
mapfile=/full/path/to/osm.xml
spherical_mercator=true

    OpenLayers Layer

    var tms = new OpenLayers.Layer.TMS("TileCache TMS Layer","http://localhost:8000/",
                { serviceVersion: "1.0.0", layername: "osm",  type: "png" });
map.addLayers([tms]);

    I pulled this from an old example of mine from the first time I got this working: http://mapnik-utils.googlecode.com/svn/example_code/tilecache/openlayers_osm.html