Plotting character patterned grobs

grid.pattern_pch() draws a plotting character pattern onto the graphic device.

grid.pattern_pch(
  x = c(0, 0, 1, 1),
  y = c(1, 0, 0, 1),
  id = 1L,
  ...,
  colour = gp$col %||% "grey20",
  fill = gp$fill %||% "grey80",
  angle = 30,
  density = 0.2,
  spacing = 0.05,
  xoffset = 0,
  yoffset = 0,
  scale = 0.5,
  shape = 1L,
  grid = "square",
  type = NULL,
  subtype = NULL,
  rot = 0,
  alpha = gp$alpha %||% NA_real_,
  linetype = gp$lty %||% 1,
  size = gp$lwd %||% 1,
  default.units = "npc",
  name = NULL,
  gp = gpar(),
  draw = TRUE,
  vp = NULL
)

Arguments

x	A numeric vector or unit object specifying x-locations of the pattern boundary.
y	A numeric vector or unit object specifying y-locations of the pattern boundary.
id	A numeric vector used to separate locations in x, y into multiple boundaries. All locations within the same id belong to the same boundary.
...	Currently ignored
colour	Stroke colour
fill	Fill colour
angle	Rotation angle in degrees
density	Approx. fraction of area the pattern fills.
spacing	Spacing between repetitions of pattern ('snpc' units between 0 and 1).
xoffset	Shift pattern along x axis ('snpc' units between 0 and 1).
yoffset	Shift pattern along y axis ('snpc' units between 0 and 1).
scale	For star polygons, multiplier (between 0 and 1) applied to exterior radius to get interior radius.
shape	An integer from 0 to 25 or NA. See graphics::points() for more details. Note we only support these shapes and do not support arbitrary ASCII / Unicode characters.
grid	Adjusts placement and density of certain graphical elements. "square" (default) is a square grid. "hex" is a hexagonal grid suitable for hexagonal and triangular tiling. "hex_circle" is a hexagonal grid suitable for circle packing. "elongated_triangle" is a grid used for the "elongated triangle" tiling.
type	Adjusts the repeating of certain aesthetics such as color. Can use any type in names_hex, names_square, or names_weave. See for pattern_hex(), pattern_square(), and pattern_weave() for more information about supported type arguments.
subtype	See for pattern_hex(), pattern_square(), and pattern_weave() for more information about supported subtype arguments.
rot	Angle to rotate regular polygon (degrees, counter-clockwise).
alpha	Alpha (between 0 and 1) or NA (default, preserves colors' alpha value).
linetype	Stroke linetype
size	Stroke linewidth
default.units	A string indicating the default units to use if x or y are only given as numeric vectors.
name	A character identifier.
gp	An object of class "gpar", typically the output from a call to the function gpar. This is basically a list of graphical parameter settings.
draw	A logical value indicating whether graphics output should be produced.
vp	A Grid viewport object (or NULL).

Value

A grid grob object invisibly. If draw is TRUE then also draws to the graphic device as a side effect.

See also

grid.pattern_regular_polygon() which is used to implement this pattern.

Examples

  if (require("grid")) {
    x_hex <- 0.5 + 0.5 * cos(seq(2 * pi / 4, by = 2 * pi / 6, length.out = 6))
    y_hex <- 0.5 + 0.5 * sin(seq(2 * pi / 4, by = 2 * pi / 6, length.out = 6))
    gp <- gpar(col = "black", fill = "lightblue")

    # pch 0-6 are simple shapes with no fill
    grid.pattern_pch(x_hex, y_hex, shape = 0:6, gp = gp,
                     spacing = 0.1, density = 0.4, angle = 0)

    # pch 7-14 are compound shapes with no fill
    grid.newpage()
    grid.pattern_pch(x_hex, y_hex, shape = 7:14, gp = gp,
                     spacing = 0.1, density = 0.4, angle = 0)

    # pch 15-20 are filled with 'col'
    grid.newpage()
    grid.pattern_pch(x_hex, y_hex, shape = 15:20, gp = gp,
                     spacing = 0.1, density = 0.4, angle = 0)

    # pch 21-25 are filled with 'fill'
    grid.newpage()
    grid.pattern_pch(x_hex, y_hex, shape = 21:25, gp = gp,
                     spacing = 0.1, density = 0.4, angle = 0)

    # using a 'basket' weave `type` with two shapes
    grid.newpage()
    grid.pattern_pch(x_hex, y_hex, shape = c(1,4), gp = gp,
                     type = "basket",
                     spacing = 0.1, density = 0.4, angle = 0)
  }