Domain map and boundaries.
getmask.Rd
These routines return the map (polygons) for drawing over a plot. Or the inversei.e. the sea becomes the inside of the polygons, e.g. to erase values over the sea.
Usage
getmap(domain=.Last.domain(), interior=TRUE,
fill=FALSE, map.database="world")
getbox(domain=.Last.domain())
getmask(domain=.Last.domain(), map.database="world")