let circleDiameter = 30;

​

function setup() {

  createCanvas(400, 50);

  frameRate(15);

  fill(color('orange'));

}

​

function draw() {

  background(color('lightblue'));

  stroke(0); // Draw the line in black.

  line(width / 2, 0, width / 2, height);

  noStroke(); // Disable stroke so that circles are not outlined.

  // Draw a circle at a random x location.

  let randomX = random(width/2, width);

  circle(randomX, height / 2, circleDiameter);

  // Draw a circle at the next noise location

  noiseOffset += 0.02;

  let noiseX = map(noise(noiseOffset), 0, 1, 0, width/2);

  circle(noiseX, height / 2, circleDiameter);

}