Loop thing

var counter = 0;

​

function setup() {

  createCanvas(windowWidth, windowHeight);

  background(0);

}

​

function draw() {

  background(0);

  rectMode(CENTER);

​

  translate(0, height / 2);

  //let num = map(mouseX, 0, width, 0, 200);

  let num = map(sin(millis()/1000), -1, 1, 10, 200);

​

  for (let y = 0; y < num; y += 1) {

    let rot = map(y, 0, num, 0, PI);

    let posx = map(y, 0, num, 0, width);

    //let col = map(y, 0, num, 0, 255);

    //stroke(col);

    push();

    translate(posx, 0);

    rotate(rot);

    noFill();

    stroke(240, 0, 0, 100 );

    //rect(mouseX, mouseY, 150, 150);

    arc(sin(millis()/1000), 0, mouseX, 150, 0, PI);

    line(mouseX, mouseY, 150, 150);

    pop();

  }

}