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Add a map layer from the Open Geospatial Consortium (OGC)

  • Статия

The atlas.layer.OgcMapLayer class can overlay Web Map Services (WMS) imagery and Web Map Tile Services (WMTS) imagery on the map. WMS is a standard protocol developed by OGC for serving georeferenced map images over the internet. Image georeferencing is the processes of associating an image to a geographical location. WMTS is also a standard protocol developed by OGC. It's designed for serving prerendered and georeferenced map tiles.

The following sections outline the web map service features supported by the OgcMapLayer class.

Web Map Service (WMS)

  • Supported versions: 1.0.0, 1.1.0, 1.1.1, and 1.3.0

  • The service must support the EPSG:3857 projection system, or handle reprojections.

  • GetFeatureInfo requires the service to support EPSG:4326 or handle reprojections.

  • Supported operations:

    Operation Description
    GetCapabilities Retrieves metadata about the service with the supported capabilities
    GetMap Retrieves a map image for a specified region
    GetFeatureInfo Retrieves feature_info, which contains underlying data about the feature

Web Map Tile Service (WMTS)

  • Supported versions: 1.0.0

  • Tiles must be square, such that TileWidth == TileHeight.

  • CRS supported: EPSG:3857 or GoogleMapsCompatible

  • TileMatrix identifier must be an integer value that corresponds to a zoom level on the map. In Azure Maps, the zoom level is a value between "0" and "22". So, "0" is supported, but "00" isn't supported.

  • Supported operations:

    Operation Description
    GetCapabilities Retrieves the supported operations and features
    GetTile Retrieves imagery for a particular tile

Overlay an OGC map layer

The url can be the base URL for the service or a full URL with the query for getting the capabilities of the service. Depending on the details provided, the WFS client may try several standard URL formats to determine how to initially access the service.

The OGC map layer sample shows how to overlay an OGC map layer on the map. For the source code for this sample, see OGC map layer source code.

A screenshot that shows the snap grid on map.

OGC map layer options

The OGC map layer options sample demonstrates the different OGC map layer options. For the source code for this sample, see OGC map layer options source code.

A screenshot that shows a map along with the OGC map layer options.

OGC Web Map Service explorer

The OGC Web Map Service explorer sample overlays imagery from the Web Map Services (WMS) and Web Map Tile Services (WMTS) as layers. You may select which layers in the service are rendered on the map. You may also view the associated legends for these layers. For the source code for this sample, see OGC Web Map Service explorer source code.

A screenshot that shows a map with a WMTS layer that comes from the world geology survey. Left of the map is a drop-down list showing the OGC services that can be selected.

You may also specify the map settings to use a proxy service. The proxy service lets you load resources that are hosted on domains that don't have CORS enabled.

Next steps

Learn more about the classes and methods used in this article:

OgcMapLayer

OgcMapLayerOptions

See the following articles, which contain code samples you could add to your maps:

Connect to a WFS service

Leverage core operations

Supported data format details