Sperm swimming outwards from a centre in form of a heart

HeartSpermExplosion.pde

//based from https://twitter.com/ntsutae/status/1227550470001946624
//https://www.openprocessing.org/sketch/841004
//resource http://mathworld.wolfram.com/HeartCurve.html

float C=0, F;
Sperm[] Sperm;
long time;
void setup() {
  size(1280, 720);
  Sperm=new Sperm[width];
  for (int i=0; i<Sperm.length; i++) {
    Sperm[i]=new Sperm(i);
  }
  time = millis();
}

void draw() {
  fill(0, 50);
  noStroke();
  rect(0, 0, width, height);
  stroke(255);
  C+=.03; // counter
  F=sin(C)*17;// gravity force
  for (int i=0; i<width; i++) {
    Sperm[i].update();
    if (time + 1000 < millis()) Sperm[i].changeFlowDirection();
  }
  if (time + 1000 < millis()) time = millis();
}
class Sperm {
  float index,x, y;
  boolean outboundMove;
  boolean nearCentre;
  Sperm(float i) {
    x=width/2;
    y=height/2;
    index=i;
    outboundMove = true;
    nearCentre = false;
  }
  void update() {
    float X, Y;
    x=(x+width)%width;
    y=(y+height)%height;
    if (x-width/2 < 20 && y-height/2 < 20) nearCentre = true;
    else nearCentre = false;
    X=x;
    Y=y;
    float n=noise((float)x/width-index, (float)y/height, C)*30;
    x+=cos(n)*3;
    y+=sin(n)*3;
    float d=dist(x, y, width/2, height/2)/F; // I dont care of zero divided. 
    if (outboundMove == true) {
      x+=16*pow(sin(radians(index)), 3);
      y+=-1*(13*cos(radians(index))-5*cos(radians(2*index))-2*cos(radians(3*index))-cos(radians(4*index)));
    } else {
      x+=(x-width/2)/d;
      y+=(y-height/2)/d;
    }
    line(X, Y, x, y);
  }
  void changeFlowDirection() {
    if (outboundMove) outboundMove = false;
    if (!outboundMove && nearCentre) outboundMove = true;
  }
}