X: [

    // Original rule

    { rule: "F[+X][-X]FX",  prob: 0.5 },

    // Fewer limbs

    { rule: "F[-X]FX",      prob: 0.05 },

    { rule: "F[+X]FX",      prob: 0.05 },

    // Extra rotation

    { rule: "F[++X][-X]FX", prob: 0.1 },

    { rule: "F[+X][--X]FX", prob: 0.1 },

    // Berries/fruits

    { rule: "F[+X][-X]FA",  prob: 0.1 },

    { rule: "F[+X][-X]FB",  prob: 0.1 }

  ],

  F: [

    // Original rule

    { rule: "FF",  prob: 0.85 },

    // Extra growth

    { rule: "FFF", prob: 0.05 },

    // Stunted growth

    { rule: "F",   prob: 0.1 },

  ]

};

​

const len = 4;

const ang = 25;

const numGens = 6;

​

let drawRules;

​

let word = "X";

​

function setup() {

  createCanvas(600, 600);

  strokeWeight(2);

  drawRules = {

    "A": () => {

      // Draw circle at current location

      noStroke();

      fill("#E5CEDC");

      circle(0, 0, len*2);

    },  

    "B": () => {

      // Draw circle at current location

      noStroke();

      fill("#FCA17D");

      circle(0, 0, len*2);

    },

    "F": () => {

      // Draw line forward, then move to end of line

      stroke("#9ea93f");

      line(0, 0, 0, -len);

      translate(0, -len);

    },

    "+": () => {

      // Rotate right

      rotate(PI/180 * -ang);

    },

    "-": () => {

      // Rotate right

      rotate(PI/180 * ang);

    },

    // Save current location

    "[": push,

    // Restore last location

    "]": pop,

  };

  noLoop();

}

​

function draw() {

  background(28);

  // Generate our L-System from the start

  word = "X";

  for(let i = 0; i < numGens; i ++) {

    word = generate();

    console.log(word);

  }

  // Draw L-System

  push();

  translate(width/2, height);

  for(let i = 0; i < word.length; i ++) {

    let c = word[i];

    if(c in drawRules) {

      drawRules[c]();

    }  

  }

  pop();

}

​

function mouseReleased() {

  draw();

}

​

function generate() {

  let next = ""

  for(let i = 0; i < word.length; i ++) {

    let c = word[i];

    if(c in rules) {

      let rule = rules[c];

      // Check if we're using an array or not

      if(Array.isArray(rule)) {

        next += chooseOne(rule); // If we are, choose one of the options

      } else {

        next += rules[c]; // Otherwise use the rule directly

      }

    } else {

      next += c;

    }

  }

  return next;

}

​

function chooseOne(ruleSet) {

  let n = random(); // Random number between 0-1

  let t = 0;

  for(let i = 0; i < ruleSet.length; i++) {

    t += ruleSet[i].prob; // Keep adding the probability of the options to total

    if(t > n) { // If the total is more than the random value

      return ruleSet[i].rule; // Choose that option

    }

  }

  return "";

}

​

​

​

​

​

​

​