let ufoY = 80

let ufoWidth = 90

​

function setup() {

  createCanvas(400, 300)

  noStroke()

}

​

function draw() {

  background("skyblue")

  drawSun()

  drawGrass()

  drawUfo()

  moveUfo()

}

​

function drawSun() {

  fill("yellow")

  circle(width, 0, height / 2)

}

​

function drawGrass() {

  fill('lightgreen')

  rect(0, height * 3 / 4, width, height * 0.25)

}

​

function drawUfo() {

  if (width * 0.4 < ufoX && ufoX < width * 0.6) {

    fill('white')

    triangle(ufoX, ufoY, ufoX + 20, height * 0.875,

      ufoX - 20, height * 0.875)

  }

  fill('gray')

  ellipse(ufoX, ufoY, ufoWidth, 30)

  ellipse(ufoX, ufoY - 12, ufoWidth / 2, 30)

}

​

function moveUfo() {

  ufoX += 1

  if (ufoX > width) {

    noLoop()

  }

}

​