Blob generator

General purpose

Algorithm for blobby shapes generation (eg. asteroids, stones, ...). Inspired by this post.

Usage

Available functions

blob

/**
 * Returns the list of coordinates of a blob.
 * More information of the algorithm here: https://gamedev.stackexchange.com/a/64266
 * @export
 * @param {object} options The options to generate the blob.
 */
export function blob (options: {
  /**
   * The number of points of the blob that should be returned.
   */
  points: number,
  /**
   * The radius of the blob if it was a perfect circle.
   */
  radius: number,
  /**
   * The number of waves the blob should have.
   */
  totalWaves: number,
  /**
   * The maximum weight of the waves. The bigger, the highest the waves will be, as if they were attracted outside the blob.
   */
  maxWaveWeight: number,
  /**
   * Normalized weight of each wave, between 0 and 1.
   */
  weights: number[],
  /**
   * Starting angle of each wave around the circle, between 0 and 1.
   */
  tetas: number[]
}): Point[]

randomBlob

/**
 * Generates a random blob and returns its list of coordinates.
 * @export
 * @param {object} options The options to generate the blob.
 * @returns {Point[]} The list of points representing the coordinates of the blob.
 */
export function randomBlob (options: {
  /**
   * The number of points of the blob that should be returned.
   */
  points: number,
  /**
   * The radius of the blob if it was a perfect circle.
   */
  radius: number,
  /**
   * The minimum amount of waves. Default is 2.
   */
  minWaves?: number,
  /**
   * The maximum amount of waves. Default is 5.
   */
  maxWaves?: number,
  /**
   * The maximum weight of the waves. The bigger, the highest the waves will be, as if they were attracted outside the blob.
   * Default is 0.25
   */
  maxWaveWeight?: number
}): Point[]

Example

const pointsArray = blob({
  // The number of points of the blob that should be returned.
  points: 360,
  // The radius of the blob if it was a perfect circle.
  radius: 25,
  // The number of waves the blob should have.
  totalWaves: 5,
  // The maximum weight of the waves. The bigger, the highest the waves will be, as if they were attracted outside the blob.
  maxWaveWeight: 0.15,
  // Weight of each wave. Should be between 0 and maxWaveWeight.
  weights: [
    0.22758758344096286,
    0.22914399498211835,
    0.48082074891715276,
    0.24720453139040366,
    0.8943967340103312
  ],
  // Starting angle of each wave around the circle, between 0 and 1.
  tetas: [
    0.5019172442558755,
    0.37216262597840677,
    0.42013817266713027,
    0.3662304499115392,
    0.7511340549973469
  ]
})

Try it

You can try the library here.