Spatial-aware north arrow
annotation_north_arrow( mapping = NULL, data = NULL, ..., height = unit(1.5, "cm"), width = unit(1.5, "cm"), pad_x = unit(0.25, "cm"), pad_y = unit(0.25, "cm"), rotation = NULL, style = north_arrow_orienteering ) GeomNorthArrow
mapping, data, ... | See Aesthetics |
---|---|
height, width | Height and width of north arrow |
pad_x, pad_y | Padding between north arrow and edge of frame |
rotation | Override the rotation of the north arrow (degrees conterclockwise) |
style | A grob or callable that produces a grob that will be drawn as the north arrow. See north_arrow_orienteering for options. |
An object of class GeomNorthArrow
(inherits from Geom
, ggproto
, gg
) of length 5.
A ggplot2 layer
The following can be used as parameters or aesthetics. Using them as
aesthetics is useful when facets are used to display multiple panels,
and a different (or missing) scale bar is required in different panels.
Otherwise, just pass them as arguments to annotation_north_arrow()
.
which_north: "grid" results in a north arrow always pointing up; "true" always points to the north pole from whichever corner of the map the north arrow is in.
location: Where to put the scale bar ("tl" for top left, etc.)
cities <- data.frame( x = c(-63.58595, 116.41214), y = c(44.64862, 40.19063), city = c("Halifax", "Beijing") ) ggplot(cities) + geom_spatial_point(aes(x, y), crs = 4326) + annotation_north_arrow(which_north = "true") + coord_sf(crs = 3995)ggplot(cities) + geom_spatial_point(aes(x, y), crs = 4326) + annotation_north_arrow(which_north = "grid") + coord_sf(crs = 3995)