Friday, December 27, 2013

Set Your Coffee-Scripts to Stun

After reviewing several HTML5 game engines, I've decided to spend some time with Phaser. My primary consideration has to be gameplay, and after trying a bunch of demos, I felt that Phaser was one of the top contenders. With comparable gameplay, I next looked at the development environment and framework.

Here is why I like Phaser:
  • No special workbench is needed. My favorite editor will work, as well as the one I happen to be using.
  • Cross platform on the dev side. I use Linux.
  • Ecma standard script - not ActionScript or anything else, but real javascript.
  • Agnostic oop - I'm not forced into any class patterns.
Best of all, due to those last two points, Phaser is compatible with coffee-script. As my tag cloud tells me, that is my favorite topic,  so with a bit of playing around, I ported this tutorial to coffee-script.

At the moment, there is a workaround patch needed for coffee-script classes to work. This could be fixed in an upcoming release, but for now we need to ensure that the prototype.constructor is set:

Phaser.Game::constructor = Phaser.Game    # patch prototype
Phaser.State::constructor = Phaser.State  # patch prototype

Update: I just downloaded Phaser 2.0.2, and found that the prototype patch described above was no longer needed.

Now the code - this is just the final listing from the demo:

class Game extends Phaser.Game

  constructor: ->

    super 800, 600, Phaser.AUTO
    @state.add 'Stage', Stage, false
    @state.start 'Stage'

class Stage extends Phaser.State

  player: null
  platforms: null
  cursors: null
  stars: null
  score: 0
  scoreText: null

  preload: ->

    @load.image 'sky', 'assets/sky.png'
    @load.image 'ground', 'assets/platform.png'
    @load.image 'star', 'assets/star.png'
    @load.spritesheet 'dude', 'assets/dude.png', 32, 48

  create: ->
    #  A simple background for our game
    @add.sprite  0, 0, 'sky'

    #  The platforms group contains the ground and the 2 ledges we can jump on
    @platforms =

    # Here we create the ground.
    ground = @platforms.create(0, @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
    ledge = @platforms.create(400, 400, 'ground')
    ledge.body.immovable = true

    ledge = @platforms.create(-150, 250, 'ground')
    ledge.body.immovable = true

    # The player and its settings
    @player = @add.sprite(32, @world.height - 150, 'dude')

    #  Player physics properties. Give the little guy a slight bounce.
    @player.body.bounce.y = 0.2
    @player.body.gravity.y = 6
    @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 =

    #  Here we'll create 12 of them evenly spaced apart
    for i in [0...12]
    #  Create a star inside of the 'stars' group
      star = @stars.create(i * 70, 0, 'star')

      #  Let gravity do its thing
      star.body.gravity.y = 6

      #  This just gives each star a slightly random bounce value
      star.body.bounce.y = 0.7 + Math.random() * 0.2

    #  The score
    @scoreText = @add.text(16, 16, 'score: 0', { fontSize: '32px', fill: '#000' })

    #  Our controls.
    @cursors = @input.keyboard.createCursorKeys()

  update: ->

    #  Collide the player and the stars with the platforms
    @physics.collide(@player, @platforms)
    @physics.collide(@stars, @platforms)

    #  Checks to see if the player overlaps with any of the stars, if he does call the collectStar function
    @physics.overlap(@player, @stars, @collectStar, 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'left')

    else if (@cursors.right.isDown)
      #  Move to the right
      @player.body.velocity.x = 150'right')

      #  Stand still
      @player.frame = 4

    #  Allow the player to jump if they are touching the ground.
    if (@cursors.up.isDown and @player.body.touching.down)
      @player.body.velocity.y = -350

  collectStar: (player, star) ->

    # Removes the star from the screen

    #  Add and update the score
    @score += 10
    @scoreText.content = 'Score: ' + @score
new Game
Lastly, compile to javascript for use in your html. While you can use coffee-script on the browser side, it impacts load time.


  1. This comment has been removed by a blog administrator.

  2. The reality star stunned in the one-piece, showing of her svelte frame at Barnes ...
    Pega Training in Chennai |
    Web Designing Training in Chennai

  3. I don't always write CoffeeScript, but when I do, I'm probably using jQuery too; I always forget the syntax for stuff. ... Vmware Training in Chennai | PHP Training in Chennai

  4. A directing content scope rubric may fluctuate starting with one media house then onto the next, however the key criteria segments are steady. reader script

  5. Such sites are important because they provide a large dose of useful information ...
    best grind and brew coffee maker 2018

  6. See more information about web design visit V8web web design