var n = 8, d = 7;

const scale = 150;

var mx;

var total = 0.01;

var offset = 0;

​

function setup(){

  createCanvas(400, 400, P2D);

  colorMode(HSB, 255);

  strokeWeight(3);

  background('#000033');

}

​

function draw(){

  translate(width/2, height/2);

  var prevX = 1 + offset, prevY = 0;

  mx = ceil((n+d)/2);

  if(n == d) mx = 1;

  for(var i = 0.01; i <= TWO_PI * mx; i += 0.01){

    var radius = cos(i* n/d) + offset;

    var x = cos(i) * radius;

    var y = sin(i) * radius;

    stroke(map(i, 0, TWO_PI*mx, 0, 255), 200, 200);

    line(prevX * scale, prevY * scale, x * scale, y * scale);

    prevX = x;

    prevY = y;

  }

  //if(total <= TWO_PI * mx) total += 0.1;

  offset += 0.005;

}