Functions to place contour labels — label

These functions compute the position of contour labels.

label_placer_fraction(
  frac = 0.5,
  rot_adjuster = isoband::angle_halfcircle_bottom()
)

label_placement_fraction(
  frac = 0.5,
  rot_adjuster = isoband::angle_halfcircle_bottom()
)

label_placer_n(n = 2, rot_adjuster = isoband::angle_halfcircle_bottom())

label_placement_n(n = 2, rot_adjuster = isoband::angle_halfcircle_bottom())

label_placer_random(
  seed = 42,
  n = 1,
  rot_adjuster = isoband::angle_halfcircle_bottom()
)

label_placement_random(
  seed = 42,
  n = 1,
  rot_adjuster = isoband::angle_halfcircle_bottom()
)

label_placer_all(rot_adjuster = isoband::angle_halfcircle_bottom())

label_placement_all(rot_adjuster = isoband::angle_halfcircle_bottom())

label_placer_flattest(
  ref_angle = 0,
  rot_adjuster = isoband::angle_halfcircle_bottom()
)

label_placement_flattest(
  ref_angle = 0,
  rot_adjuster = isoband::angle_halfcircle_bottom()
)

label_placer_minmax(
  direction = c("vertical", "horizontal"),
  rot_adjuster = isoband::angle_halfcircle_bottom()
)

label_placement_minmax(
  direction = c("vertical", "horizontal"),
  rot_adjuster = isoband::angle_halfcircle_bottom()
)

Arguments

frac: A numeric vector with values between 0 and 1 representing where in the contour to put labels (i.e. frac = 0.5 puts labels at the midpoint).
rot_adjuster: A function that standardizes the rotation angles of the labels. See e.g. isoband::angle_halfcircle_bottom.
n: Number of labels to put.
seed: Seed to use for randomly choosing where to put labels.
ref_angle: Angle (in degrees counter-clockwise from East) to try to approximate labels.
direction: Direction in which to compute the maximum and minimum.