Raster tiles

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Raster tiles are square bitmap graphics displayed in a grid arrangement to show a map. An alternative approach is vector tiling. The general concept of tiling and the difference between raster and vector tiles is described at Tiles.

This page includes lots of information and technical detail. If you want to use map tiles in your web page or application you can have a look at this tutorial about how to use OpenStreetMap tiles.

Graphical Map Tiles

Map tiles are typically 256×256 pixel images. e.g.:

this example tile

Tiles are not always in these dimensions; for example there could be 64×64 pixel images, however 256×256 pixel images are a de facto standard. 512×512 pixel seems to be the usual size of high-resolution tiles.

A "tileset" typically includes enough tiles to form a very large image, if they were shown all at once, and also several zoom levels. Generally the idea is not to show them all at once, but to display a particular area of the map on a website. Normally this is done using a JavaScript map library to provide panning and zooming functionality, and request downloading of new tiles as necessary to show the user new areas of the map (a Slippy Map).

Using tiles

Technical data

Development

Tile providers

See Raster tile providers.

Also see for example map compare service at bbbike.org. Please obey the usage restrictions of each tile server if you use it heavily!

More webservices to display different OSM based tiles are mapstyle.petschge.de and Leaflet Provider Demo.

Tiled map data

  • QuadTiles, a scheme to make OSM database indexed by tiles
  • OJW's tile data server, first implementation of a cacheable data server, that servs data in the same way as the tileserver.
  • Tile data server, generic definition of how data served as tiles should work. (written by ojw as well...)

See also

Links

  • Switch2OSM, The Basics This page gives some introductory information on the tiles, licence and JavaScript libraries to display the tiles.