​

let pos_origin = {x:200, y:200};

let squiggliness = 0.5;

let pos = pos_origin;

let dir = 0; // number between 0 and 2*PI

let step = 5;

​

function setup() {

  createCanvas(600, 600);

  background(0);

  stroke('rgba(100,50,255,0.6)');

  strokeWeight(5);

  squiggliness = PI/4;

}

​

function turn(angle) {

  dir += angle;

  while (dir > 2*PI) {

    dir -= 2*PI;

  }

  while (dir < 0) {

    dir += 2*PI;

  }

}

​

function forward() {

  new_x = pos.x + cos(dir)*step;

  new_y = pos.y + sin(dir)*step;

  // console.log("Next point: ")

  return {x:new_x, y:new_y};

}

​

function draw() {

  if(frameCount%20 == 0) // slow fadeout

    fill("rgba(255,255,255, 0.1)");

    circle(pos.x, pos.y, 100)

  let p = Math.random();

  let turn_factor = Math.random();

  if(p < 0.5)

    turn(squiggliness*turn_factor);

  else //if(p < 0.8)

    turn (-squiggliness*turn_factor);

  //else

  //  {} // continue at prev heading

  next_pos = forward();

  line(pos.x, pos.y, next_pos.x, next_pos.y);

  pos = next_pos;

  if (pos.x > width || pos.y > height || pos.x < 0 || pos.y < 0) {

    pos = pos_origin;

    spawnNew(pos);

  }

​

}

​

function spawnNew(pos) {

  pos_origin = pos;

  let red_pct = Math.random();

  let blue_pct = Math.random();

  if (red_pct < .1)

      red_pct = .1;

  if (blue_pct < .2)

      blue_pct = .2;

  stroke(red_pct*255,10,blue_pct*255,0.6*255);

}

​

function mousePressed() {

  spawnNew({x:mouseX, y:mouseY});

​

}