​

let a = x => {

  return 240 - 100 * sin((x - 245) * (x - 245) / 10000 + 1);

}

​

let b = x => {

  return 340 - 100 * sqrt((x - 320) * (x - 320) / 10000 + 1);

}

​

let aPath = [];

let bPath = [];

let spacing = 1;

let t = 0;

​

let play = true;

​

function setup() {

  createCanvas(640, 480);

  for (let i = width / 3; i < width * 2 / 3; i += spacing) {

    let xa = i - 150;

    let ya = a(i);

    let va = createVector(xa, ya);

    aPath.push(va);

    let xb = i + 150;

    let yb = b(i);

    let vb = createVector(xb, yb);

    bPath.push(vb);

  }

}

​

function keyPressed() {

  if (key == " ") {

    if (play) {

      play = false;

    } else {

      play = true;

    }

  }

}

​

function draw() {

  background(255);

  stroke(0);

  noFill();

  strokeWeight(3);

  beginShape();

  let time = (sin(t) + 1) / 2;

  if (play) {

    t += 0.03;

  }

  for (let i = 0; i < aPath.length; i++) {

    let qv = aPath[i];

    let cv = bPath[i];

    let x = lerp(qv.x, cv.x, time);

    let y = lerp(qv.y, cv.y, time);

    vertex(x, y);

  }

  endShape();

  fill(0);

  noStroke();

  textAlign(CENTER);

  textSize(40);

  text("Playing: " + play, width / 2, 50);

}