let grassTexture

let groundElevation = 100

​

function preload() {

  grassTexture = loadImage('grass.png')

}

​

function setup() {

  createCanvas(500, 500, WEBGL);

  noStroke()

}

​

function draw() {

  directionalLight(255, 255, 255, 1, 1, -1)

  pointLight(255, 255, 255, ufo.x, ufo.y-30, ufo.z)

  background('#330033');

  drawGround();

  drawUfo();

  moveUfo();

}

​

function drawGround() {

  push()

  texture(grassTexture)

  spotLight(255, 255, 255, ufo.x, ufo.y, ufo.z, 0, 1, 0, Math.PI/6, 3)

  translate(0, groundElevation, 0)

  rotateX(radians(90))

  plane(900, 550)  

  pop()

}

​

function drawUfo() {

  push()

  translate(ufo.x, ufo.y, ufo.z)

  rotateY(ufo.spin)

  ellipsoid(100, 20, 100)

  translate(0, -15, 0)

  sphere(30)

  translate(0, 35, 0)

  emissiveMaterial('white')

  sphere(10)

  pop()

}

​

function moveUfo() {

  ufo.spin += 0.01

  if (ufo.z < 0) {

    ufo.z++  

  } else if (ufo.y < 100) {

    ufo.y++

  } else {

    noLoop()

  }

}

​