const MAX_REGION_LEVEL: 24
The deepest subdivision an address can carry.
Twenty-four halvings of a cube face take an Earth-sized body from 10,000 km
to 60 cm, which is the smallest ground a region has ever needed to name. It
is a property of the address space rather than of the renderer: what the
streamer will actually ask for is surfaceDetailFloor, which is a property
of the field.