## Not run:
#
# imap() # Zoom into an area, right-click to stop.
#
# gdist.total(draw.lines(rainbow(10), lwd=4)) # Left-click two or more times, right-click to stop.
#
# # The total distance of the polygon's perimeter:
# gdist.total(draw.polygon()) # Left-click three or more times, right-click to stop.
#
# # The total distance of contiguous points (those not separated by NA's).
# gdist.total(select.pts(imap()[[1]]$ll)) # Zoom in to an area, right-click, and then select points by creating a polygon with left-clicks.
#
# ## End(Not run)
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