perlin_circle.R

perlin_circle <- function(
  cx = 0, cy = 0, n = 100, noise_max = 0.5, octaves = 2, r_min = 0.5, r_max = 1
) {
  tibble::tibble(
    angle = seq(0, 2*pi, length.out = n),
    xoff = scales::rescale(x = cos(angle), from = c(-1, 1), to = c(0, noise_max)),
    yoff = scales::rescale(x = sin(angle), from = c(-1, 1), to = c(0, noise_max)),
    r = scales::rescale(
      x = ambient::fracture(
        noise = ambient::gen_simplex,
        fractal = ambient::fbm,
        x = xoff,
        y = yoff,
        octaves = octaves
      ),
      from = c(-0.5, 0.5),
      to = c(r_min, r_max)
    ),
    x = r * cos(angle) + cx,
    y = r * sin(angle) + cy
  )
}

pic <- ggplot2::ggplot(
  data = perlin_circle(),
  mapping = ggplot2::aes(x = x, y = y)
) +
  ggplot2::geom_path() +
  ggplot2::coord_equal()

plot(pic)

credit for the core idea goes to @will-r-chase