index.js

const Phaser = require('phaser-ce');

let platforms;
let player;
let cursors;
let stars;
let score = 0;
let scoreText;

const preload = (game) => {
  game.load.image('sky', 'assets/sky.png');
  game.load.image('ground', 'assets/platform.png');
  game.load.image('star', 'assets/star.png');
  game.load.spritesheet('dude', 'assets/dude.png', 32, 48);
};


const create = (game) => {
  //  We're going to be using physics, so enable the Arcade Physics system
  game.physics.startSystem(Phaser.Physics.ARCADE);
  //  A simple background for our game
  game.add.sprite(0, 0, 'sky');
  //  The platforms group contains the ground and the 2 ledges we can jump on
  platforms = game.add.group();
  //  We will enable physics for any object that is created in this group
  platforms.enableBody = true;
  // Here we create the ground.
  const ground = platforms.create(0, game.world.height - 64, 'ground');
  //  Scale it to fit the width of the game (the original sprite is 400x32 in size)
  ground.scale.setTo(2, 2);
  //  This stops it from falling away when you jump on it
  ground.body.immovable = true;
  //  Now let's create two ledges
  const ledge = platforms.create(400, 400, 'ground');
  ledge.body.immovable = true;
  const ledge2 = platforms.create(-150, 250, 'ground');
  ledge2.body.immovable = true;
  player = game.add.sprite(32, game.world.height - 150, 'dude');

  //  We need to enable physics on the player
  game.physics.arcade.enable(player);

  //  Player physics properties. Give the little guy a slight bounce.
  player.body.bounce.y = 0.2;
  player.body.gravity.y = 300;
  player.body.collideWorldBounds = true;

  //  Our two animations, walking left and right.
  player.animations.add('left', [0, 1, 2, 3], 10, true);
  player.animations.add('right', [5, 6, 7, 8], 10, true);

  //  Finally some stars to collect
  stars = game.add.group();

  //  We will enable physics for any star that is created in this group
  stars.enableBody = true;

  //  Here we'll create 12 of them evenly spaced apart
  for (let i = 0; i < 12; i++) {
    //  Create a star inside of the 'stars' group
    const star = stars.create(i * 70, 0, 'star');
    //  Let gravity do its thing
    star.body.gravity.y = 300;
    //  This just gives each star a slightly random bounce value
    star.body.bounce.y = 0.7 + Math.random() * 0.2;
  }
  scoreText = game.add.text(16, 16, 'score: 0', { fontSize: '32px', fill: '#000' });
  cursors = game.input.keyboard.createCursorKeys();
};

const update = (game) => {
  game.physics.arcade.collide(player, platforms);
  game.physics.arcade.collide(stars, platforms);
  // Checks to see if the player overlaps with any of the stars,
  // if he does call the collectStar function
  game.physics.arcade.overlap(player, stars, (player, star) => {
    // Removes the star from the screen
    star.kill();
    score += 10;
    scoreText.text = `Score: ${score}`;
  }, null, this);
  //  Reset the players velocity (movement)
  player.body.velocity.x = 0;
  if (cursors.left.isDown) {
    //  Move to the left
    player.body.velocity.x = -150;
    player.animations.play('left');
  } else if (cursors.right.isDown) {
    //  Move to the right
    player.body.velocity.x = 150;
    player.animations.play('right');
  } else {
    //  Stand still
    player.animations.stop();
    player.frame = 4;
  }
  //  Allow the player to jump if they are touching the ground.
  if (cursors.up.isDown && player.body.touching.down) {
    player.body.velocity.y = -350;
  }
};

new Phaser.Game(800, 600, Phaser.AUTO, 'app', { preload, create, update });