opaque

True if the WmsLayer content should be considered opaque, false otherwise. The WMS layer's opaque property describes the layer's data content, not the picture format of the map response. A true value indicates that the map data are mostly or completely opaque. A false value indicates that the map data represent vector features that probably do not completely fill space. In practice, a layer with opaque set to true is a good candidate for use as a basemap.