R/fractal-fbm.R

In ambient: A Generator of Multidimensional Noise

#' Fractional Brownian Motion fractal
#'
#' This is the archetypal fractal used when generating perlin noise. It works
#' simply by adding successive values together to create a final value. As the
#' succesive values are often calculated at increasing frequencies and the
#' strength is often decreasing, it will create the impression of ever-smaller
#' details as you zoom in. This function is intended to be used in conjunction
#' with [fracture()]
#'
#' @param base The prior values to modify
#' @param new The new values to modify `base` with
#' @param strength A value to modify `new` with before applying it to `base`
#' @param ... ignored
#'
#' @family Fractal functions
#'
#' @export
#'
#' @examples
#' grid <- long_grid(seq(1, 10, length.out = 1000), seq(1, 10, length.out = 1000))
#'
#' grid$simplex <- fracture(gen_simplex, fbm, octaves = 8, x = grid$x, y = grid$y)
#' plot(grid, simplex)
#'
fbm <- function(base, new, strength, ...) {
  base + new * strength
}