Usage
addArrowMark(pos=grid.locator(), label=NULL, angle=15, length=unit(.25, "inches"), col="red", cex=1, quadrant=4, type="closed", vp=NULL)
Arguments
pos
A unit object representing the location of arrow mark to be placed
at current viewport. Default is the value of grid.locator, which will get the
location of the mouse click.
label
A character or expression vector.
angle
A parameter passed into grid::arrow function. The angle of arrow
head in degrees (smaller numbers produce narrower, pointier arrows). Essentially
describes the width of the arrow head.
length
A parameter passed into grid::arrow function. Aunit specifying
the length of the arrow head.
cex
Multiplier applied to fontsize
quadrant
the direction of arrow, 1: to bottomleft, 2: to bottomright,
3: to topright, 4: to topleft
type
A parameter passed into grid::arrow function. One of "open" or "closed"
indicating whether the arrow head should be a closed triangle.
vp
A Grid viewport object. It must be output of viewTracks