Plot graticules

Display graticules and labels on a map.

Usage

mf_graticule(
  x,
  col,
  lwd = 1,
  lty = 1,
  expandBB = rep(0, 4),
  label = TRUE,
  pos = c("top", "left"),
  cex = 0.7,
  extent = x,
  bg,
  add = TRUE
)

Arguments

x

object of class sf, sfc or SpatRaster

col

graticules and label color

lwd

graticules line width

lty

graticules line type

expandBB

fractional values to expand the bounding box with, in each direction (bottom, left, top, right)

label

whether to add labels (TRUE) or not (FALSE)

pos

labels positions ("bottom", "left", "top" and / or "right")

cex

labels size

extent

object with an st_bbox method to define plot extent; defaults to x. extent and x must use the same CRS.

bg

background color of the map, hex code or color name given by colors, ignored if add = TRUE

add

whether to add the layer to an existing plot (TRUE) or not (FALSE)

Value

An (invisible) layer of graticules is returned (LINESTRING).

Use of graticules

From sf::st_graticule(): "In cartographic visualization, the use of graticules is not advised, unless the graphical output will be used for measurement or navigation, or the direction of North is important for the interpretation of the content, or the content is intended to display distortions and artifacts created by projection. Unnecessary use of graticules only adds visual clutter but little relevant information. Use of coastlines, administrative boundaries or place names permits most viewers of the output to orient themselves better than a graticule."

Examples

mtq <- mf_get_mtq()
mf_map(mtq, expandBB = c(0, .1, .1, 0))
mf_graticule(mtq)


mf_graticule(
  x = mtq,
  col = "coral4",
  lwd = 2,
  lty = 2,
  expandBB = c(.1, 0, 0, .1),
  label = TRUE,
  pos = c("right", "bottom"),
  cex = .8,
  add = FALSE
)
mf_map(mtq, add = TRUE)