A basemap layer is a layer that provides geographic context to the scene. The following is a list of possible basemap layer types.
Referenced by: baseMap
Can be one of the following:
- Image Service Layer (ArcGISImageServiceLayer)
 - Map Service Layer (ArcGISMapServiceLayer)
 - OpenStreetMap Layer (OpenStreetMap)
 - Raster Data Layer
 - Scene Layer (ArcGISSceneServiceLayer)
 - Tiled Image Service Layer (ArcGISTiledImageServiceLayer)
 - Tiled Map Service Layer (ArcGISTiledMapServiceLayer)
 - Vector Tile Layer (VectorTileLayer)
 - Web Coverage Service Layer (WCS)
 - Web Tiled Layer (WebTiledLayer)
 - WMS Layer (WMS)