color scheme to be used. By default uses tim.colors if
available or a generic gray scale.
zlim
the minimum and maximum values for which colors should be
plotted, defaulting to the range of data.
add
logical, if true adds to current plot.
legendpos
if package fields is loaded, puts a legend at that position.
Details
The function germany.plot super-seeds
map.landkreis (it is several factors faster).
The perfect position of the legend is an art per se and depends on
various par parameters. See also the source code of the function
image.plot of fields.
References
The code of map.landkreis is very similar to
germany.map from the package INLA.