arc-2.js

function setup() {
  createCanvas(720, 400);
}

function draw() {
  background(random(0, 255), random(0, 255), random(0, 255));
  noStroke(0);
  for (var i = 0; i < 50; i++) {
    var x1 = random(0, width);
    var y1 = random(0, height);
    var x2 = random(0, width);
    var y2 = random(0, height);
    var x3 = random(0, width);
    var y3 = random(0, height);
    var x4 = random(0, width);
    var y4 = random(0, height);
    fill(random(0, 255), random(0, 255), random(0, 255), random(20, 120));
    arc(x1, y1, x2, y2, PI / 2, PI);
    arc(x3, y3, x4, y4, PI / 2, PI);
    rect(x1, y1, 2, y2);
    rect(x3, y3, x4, 2);
    ellipse(x1, y1, 15, y2);
    ellipse(x3, y3, x4, 15);
  }
  frameRate(5);
}