Description
Add a Scale Bar to 'OpenStreetMap' Plots.
Description
Functionality to handle and project lat-long coordinates, easily download background maps and add a correct scale bar to 'OpenStreetMap' plots in any map projection.
README.md
intro
OSMscale is an R package to easily handle and project lat-long coordinates, download background maps and add a correct scale bar to 'OpenStreetMap' plots in any map projection. There are some other spatially related miscellaneous functions as well.
OSMscale is available on CRAN:
It relies on OpenStreetMap to do the actual work, thus rjava must be available, see installation tips.
usage
# installation:
install.packages("OSMscale")
library(OSMscale)
# table with lat-long coordinates:
d <- read.table(sep=",", header=TRUE, text=
"lat, long
55.685143, 12.580008
52.514464, 13.350137
50.106452, 14.419989
48.847003, 2.337213
51.505364, -0.164752")
pointsMap(lat, long, data=d)
# projections:
png("ExampleMap.png", width=4, height=3, units="in", res=150)
map <- pointsMap(lat, long, data=d, type="nps", proj=putm(d$long), scale=FALSE)
scaleBar(map, abslen=500, y=0.8, cex=0.8)
lines(projectPoints(d$lat, d$long), col="blue", lwd=3)
points(projectPoints(52.386609, 4.877008, to=putm(zone=32)), cex=3, lwd=2, col="purple")
dev.off()
