Class Landscape defines a landscape
thelandscapeA SpatialPolygonsDataFrame
xminLeft x-axis coordinate (in meters)
xmaxRight x-axis coordinate (in meters)
yminBottom y-axis coordinate (in meters)
ymaxTop y-axis coordinate (in meters)
nNumber of fields in the landscape
Landscape objects can be created by calling of the allocator new("Landscape", ...), or (preferred) by calling to the function simulateLandscape or loadLandscape.