[R-sig-Geo] distance in package raster

[Agustin Lobo]

Hi

According to the manual page for distance in package raster
"The function calculates the distance to cells of a RasterLayer that are NA."

wouldn't it be better letting the user select the actual value(s)
to be considered as focal pixels? The package is mainly intended to
process large raster layers, so avoiding the need of modifying the
raster prior to run the command would make sense (few users are going
to have the focal points as NA).

Thanks for your attention,

Agus