​

function setup() {

  createCanvas(500, 300)

  noStroke()

}

​

function draw() {

  background("skyblue")

  drawGrass()

  drawSun()

  drawUfo()

  moveUfo()

}

​

function drawGrass() {

  fill("lightgreen")

  rect(0, height * 0.75, width, height * 0.25)

}

​

function drawSun() {

  fill("yellow")

  circle(width, 0, 200)

}

​

function drawUfo() {

  fill("gray")

  ellipse(ufo.x, ufo.y, ufo.width, 20)

  ellipse(ufo.x, ufo.y - 10, ufo.width / 2, 25)

}

​

function moveUfo() {

  ufo.x += ufo.speed

  if (ufo.x > width || ufo.x < 0) {

    ufo.speed = -ufo.speed

  }

}

​