Infinite Heart curve loop

InfiniteHeartCurveLoop.pde

//http://mathworld.wolfram.com/HeartCurve.html
float a=0; //angle
float x, y;
float scaleDiv = 40; //scale divisor for the size of the heart
void setup() {
  size(720, 720);
  colorMode(HSB, 360);
  background(0);
  noStroke();
}
void draw() {
  //some gray lines on background
  stroke(100, 10);
  for (int i = 20; i < width; i += 20) {
    if (random(1)> 0.7) continue;
    line(0, i, width, i);
  }
  translate(width/2, height/2);
  a++;
  x=16*pow(sin(radians(a)), 3) * width/scaleDiv;
  y=-1*(13*cos(radians(a))-5*cos(radians(2*a))-2*cos(radians(3*a))-cos(radians(4*a))) * width/scaleDiv;
  float colour = (a+x/2+y/2)%360;
  fill(colour, 360, 360);
  circle(x, y, 15);
  translate(-width/2, -height/2);
  copy(this.get(), 0, 0, width, width, 1, 1, width-2, width-2); //Thanks @Hau_Kun for this trick
}