createCanvas(600, 600);

  let delta = 0.01;

  let r0 = 200;

  let sins = [];

  let coses = [];

  num_modes = 10;

  noise_amp = 20;

  // center the coordinate system

  translate(width/2,height/2);

  background(0);

  stroke(255,5);

  noFill(0);

  // now here is the drawing

  for (let i=1; i<1000; i++) {

    // now let's initiate a bunch of random Fourier modes

    r = r0;

    for (let j = 1; j < num_modes; j++) {

      sins[j]=(random()-0.5)*noise_amp*j;

      coses[j]=(random()-0.5)*noise_amp*j;

      r = r + coses[j];

    }

    // initialized.

    x_old = r;

    y_old = 0;

    for (let theta=0; theta<(2*PI); theta+=delta) {

​

      r = r0;

      // add up all the modes. 

      for (let j = 1; j < num_modes; j ++) {

        r = r + sins[j]*sin(j*theta) + coses[j]*cos(j*theta);

      }

      x = r*cos(theta);

      y = r*sin(theta);

      // draw the line. 

      //line(r*cos(theta-delta),r*sin(theta-delta),r*cos(theta),r*sin(theta));

      line(x_old,y_old,x,y);

      x_old = x;

      y_old = y;

    }

    //circle(0,0,10*i);

    //circle(0,0,30);

  }

}

​

function draw() {

}