Hide room

Many creators will use this programm for VTT (virtual table top) so it would be nice to have an option to hide rooms untill enabled by the DM.
This feature should put the room and its walls either black or to the default terrain of the map. This way players can see there is a closed door but can not know untill the DM allows it if there is a 3x3 room behind, a hallway, or a cliff.