gws.base.map

Maps and the map action.

A map holds the root of a layer tree together with the CRS, extent, center and the resolutions (zoom levels) shared by its layers. Each project has a map. The map’s layers are created as children of an implicit group root layer, which passes the map extent, resolutions and CRS down the tree (see gws.base.layer).

Submodules:

  • core: the default map object with its Config and Props. The CRS defaults to Web Mercator. Without an extent the map covers the maximum extent of its CRS; the center defaults to the center of the extent. The title defaults to the title of the project.

  • action: the map action. Its commands serve layer images as boxes (mapGetBox) and tiles (mapGetTile), legends (mapGetLegend), layer descriptions (mapDescribeLayer) and features (mapGetFeatures) to the client. Layers build the URLs for these commands with Layer.url_path_for. Image commands answer with a transparent pixel when the layer renders nothing or rendering fails; the failure is logged.

Example:

actions+ { type "map" }

projects+ {
    title "City map"
    map {
        crs 25832
        extent [ 280000 5640000 300000 5660000 ]
        zoom.scales [ 100000 50000 25000 10000 5000 ]
        zoom.initScale 25000
        layers+ { type "qgis" provider.path "/data/city.qgs" }
    }
}

Source code: gws.base.map

Submodules