gridpattern (version 1.3.1)

grid.pattern_ambient: Ambient patterned grobs

Description

grid.pattern_ambient() draws noise patterns onto the graphic device powered by the ambient package.

Usage

grid.pattern_ambient(
  x = c(0, 0, 1, 1),
  y = c(1, 0, 0, 1),
  id = 1L,
  ...,
  type = "simplex",
  fill = gp$fill %||% "grey80",
  fill2 = "#4169E1",
  frequency = 0.01,
  interpolator = "quintic",
  fractal = switch(type, worley = "none", "fbm"),
  octaves = 3,
  lacunarity = 2,
  gain = 0.5,
  pertubation = "none",
  pertubation_amplitude = 1,
  value = "cell",
  distance_ind = c(1, 2),
  jitter = 0.45,
  res = getOption("ggpattern_res", 72),
  alpha = NA_real_,
  default.units = "npc",
  name = NULL,
  gp = gpar(),
  draw = TRUE,
  vp = NULL
)

Value

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

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.

type

Either cubic, perlin, simplex, value, white, or worley

fill

Colour.

fill2

Second colour.

frequency

Determines the granularity of the features in the noise.

interpolator

How should values between sampled points be calculated? Either 'linear', 'hermite', or 'quintic' (default), ranging from lowest to highest quality.

fractal

The fractal type to use. Either 'none', 'fbm' (default), 'billow', or 'rigid-multi'. It is suggested that you experiment with the different types to get a feel for how they behaves.

octaves

The number of noise layers used to create the fractal noise. Ignored if fractal = 'none'. Defaults to 3.

lacunarity

The frequency multiplier between successive noise layers when building fractal noise. Ignored if fractal = 'none'. Defaults to 2.

gain

The relative strength between successive noise layers when building fractal noise. Ignored if fractal = 'none'. Defaults to 0.5.

pertubation

The pertubation to use. Either 'none' (default), 'normal', or 'fractal'. Defines the displacement (warping) of the noise, with 'normal' giving a smooth warping and 'fractal' giving a more eratic warping.

pertubation_amplitude

The maximal pertubation distance from the origin. Ignored if pertubation = 'none'. Defaults to 1.

value

The noise value to return. Either

• 'value' (default) A random value associated with the closest point

• 'distance' The distance to the closest point

• 'distance2' The distance to the nth closest point (n given by distance_ind[1])

• 'distance2add' Addition of the distance to the nth and mth closest point given in distance_ind

• 'distance2sub' Substraction of the distance to the nth and mth closest point given in distance_ind

• 'distance2mul' Multiplication of the distance to the nth and mth closest point given in distance_ind

• 'distance2div' Division of the distance to the nth and mth closest point given in distance_ind

distance_ind

Reference to the nth and mth closest points that should be used when calculating value.

jitter

The maximum distance a point can move from its start position during sampling of cell points.

res

Assumed resolution (in pixels per graphic device inch) to use when creating array pattern.

alpha

Alpha (between 0 and 1) or NA (default, preserves colors' alpha value).

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).

See Also

For more information about the noise types please see the relevant ambient documentation: ambient::noise_cubic(), ambient::noise_perlin(), ambient::noise_simplex(), ambient::noise_value(), ambient::noise_white(), and ambient::noise_worley(). grid.pattern_plasma() provides an alternative noise pattern that depends on magick.

Examples

 if (requireNamespace("ambient", quietly = TRUE)) {
   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))
   grid.pattern_ambient(x_hex, y_hex, fill = "green", fill2 = "blue")
 }
 if (requireNamespace("ambient")) {
   grid::grid.newpage()
   grid.pattern_ambient(x_hex, y_hex, fill = "green", fill2 = "blue", type = "cubic")
 }