When adding custom map layers from a Tile XYZ web service, it would be useful to be able to specify the zoom levels for displaying the layer.

For example I have access to a service that allows me to specify two layers, one that provides a topographiv map suitable for display at a scale of 1:50k and one suitable for display at 1:250k. I would like to specify thet the 1:50k layer only displays in Fulcrum for zoom levels 13 to 14 and the 1:250k layer to display at only levels 10 to 12. This could be achieved by having a minimum and maximum zoom level field when creating a new map layer.

This would allow both layers to be turned on and they would smoothly switch at the specified zoom levels when viewing the map view. Outside of the specified zoom levels any other lower ordered or default base map could display.