Web Map Tiling

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Siehe auch: WMS, Geovisualisierung, Hintergrundkarten (Base Maps)

Allgemeines

Software

Tools:

  • https://github.com/geometalab/pyGeoTile - Python package to handle tiles and points of different projections, in particular WGS 84 (Latitude, Longitude), Spherical Mercator (Meters), Pixel Pyramid and Tiles (TMS, Google, QuadTree).

Clients:

Servers:

Wissenswertes

Erläuterungen zum Zoom-Level und Massstab, Meter pro Pixel am Boden, etc. am Beispiel der OpenStreetMap-Haupt-Karte, siehe OSM Wiki 'Zoom levels', OSM Wiki 'Slippy_map_tilenames' und OSM Talk-de

Tipps:

Bekannte kostenlose WMTS:

  • MapBox: need no introduction, easily the biggest and slickest OSM-powered operation out there. Some really great technology, smart guys (they've hired a lot of the brightest stars of OSM), and a bigger commitment to "giving back to OSM" than CloudMade had. Wide range of plans from free to "Enterprise". http://mapbox.com/
  • See also https://www.mapbox.com/developers/api/#Map.resources (JSONP/CORS)
  • MapQuest Open: free tiles, good all-round cartography, high availability and very generous terms of use. The default option for anyone who "just wants a map". http://open.mapquest.com/
  • Thunderforest: do a range of attractive specialist cartographies, of which OpenCycleMap is the best known, and can design and host styles to order. http://thunderforest.com/
  • Obsolet: Cloudmade
  • HiRes/Retina:
  • Satellitenbild:
    • Google Maps Satellite (Achtung: Lizenz!)
    • MapBox Satellite
    • SwissImage von geo admin API (nur Schweiz)
    • Nur bedingt nützlich: Bing, etc.

Spezifikationen

Weblinks:

XYZ

Google Maps API / Bing SDK / OpenStreetMap API.

Achtung: Es gibt inkompatible Tiling-Spezifikationen, bzw. Implementationen: "Google Maps, Microsoft Bing/Virtual Earth, Yahoo Maps, and other commercial API providers as well as OpenStreetMap and OpenAerialMap are using the same projection and tiling profile and tiles are therefore compatible. The extents of all tiles as well as the zoom levels (resolution in meters per pixel) are predefined for the whole earth. Difference is only in the way how the equivalent tiles are indexed. There are three main systems of tile adressing: Google XYZ, Microsoft QuadTree and from the open-source world comming TMS (Tile Map Service). (Source: [3]; siehe dazu auch [4].

WMTS

(Haupartikel Web Map Tile Service)

OpenGIS Web Map Tile Service (WMTS) Interface Standard. Logisch gesehen ein Profil von WMS, doch die konkrete Spezifikation ist (leider) eigenständig. Es verschiedene unterschiedliche API u.a. wegen der Verbreitung von Google Maps API und Open Source-Implementationen. OGC hat einen 'harmonisierten' Vorschlag gemacht, der jedoch kompliziert ist (siehe unten).

OGC's candidate WMTS Interface Standard: Aus giscafe.com:

The candidate WMTS Interface Standard is much like the OGC’s popular Web Map Server (WMS) Interface Standard, but it enables better server performance in applications that involve many simultaneous requests. To improve performance, instead of creating a new image for each request, it returns small pre-generated images (e.g., PNG or JPEG) or reuses identical previous requests that follow a discrete set of tile matrices. This proposed standard provides support for multiple architectural patterns – KVP, REST and SOAP.

Reference implementations: Geowebcache, Carbonarc project and some others.

The WMTS spec is much more complex, and 'fully featured', as is common in specs designed by committee. Practically speaking, if TMS does what you need, you won't need WMTS, and I can't imagine that anyone on this list practically needs WMTS over TMS. [...]

-- Christopher Schmidt on the TileCache mailing list

TMS

Tile Map Service (TMS) from OSGeo. Predecessor of WMTS. Still supported by GDAL (and QGIS "Load Raster...")

Reference implementations: TileCache Server (http://www.tilecache.org), GDAL, Worldkit Client http://worldkit.org/tilemap/, OpenLayers Client: http://openlayers.org/, Cadcorp SIS Clients. More tile implementations -- "WMS-C", Virtual Earth style addressing, WorldWind, Mobile GMaps, etc.