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Here you can Sed posuere consectetur est at lobortis. Donec ullamcorper nulla non metus auctor fringilla. Maecenas sed diam eget risus varius blandit sit amet non magna. Donec id elit non mi porta gravida at eget metus. Praesent commodo cursus magna, vel scelerisque nisl consectetur et.

HTML

            
              <div id="container">
   <div id="board-container">
        <div class="shine-container">
            <div class="shine"></div>
        </div>
        <div id="board"></div>
          
        <div class="info-container">
            <button id="start-button" class="state-driven"><span class="re state-driven">RE</span>START</button>
            <div class="flex"></div>
            <div id="score">0</div>
        </div>
    </div> 
    <div class="controls">
        <span class="keyboard"> Use keyboard arrow keys to control</span>
        <span class="touch">Swipe up, down, left or right to control.</span>
    </div>
</div>

<a href="https://github.com/ste-vg/snake" target="_blank" class="github-corner" aria-label="View source on Github"><svg width="80" height="80" viewBox="0 0 250 250" style="fill:#151513; color:#fff; position: absolute; top: 0; border: 0; right: 0;" aria-hidden="true"><path d="M0,0 L115,115 L130,115 L142,142 L250,250 L250,0 Z"></path><path d="M128.3,109.0 C113.8,99.7 119.0,89.6 119.0,89.6 C122.0,82.7 120.5,78.6 120.5,78.6 C119.2,72.0 123.4,76.3 123.4,76.3 C127.3,80.9 125.5,87.3 125.5,87.3 C122.9,97.6 130.6,101.9 134.4,103.2" fill="currentColor" style="transform-origin: 130px 106px;" class="octo-arm"></path><path d="M115.0,115.0 C114.9,115.1 118.7,116.5 119.8,115.4 L133.7,101.6 C136.9,99.2 139.9,98.4 142.2,98.6 C133.8,88.0 127.5,74.4 143.8,58.0 C148.5,53.4 154.0,51.2 159.7,51.0 C160.3,49.4 163.2,43.6 171.4,40.1 C171.4,40.1 176.1,42.5 178.8,56.2 C183.1,58.6 187.2,61.8 190.9,65.4 C194.5,69.0 197.7,73.2 200.1,77.6 C213.8,80.2 216.3,84.9 216.3,84.9 C212.7,93.1 206.9,96.0 205.4,96.6 C205.1,102.4 203.0,107.8 198.3,112.5 C181.9,128.9 168.3,122.5 157.7,114.1 C157.9,116.9 156.7,120.9 152.7,124.9 L141.0,136.5 C139.8,137.7 141.6,141.9 141.8,141.8 Z" fill="currentColor" class="octo-body"></path></svg></a><style>.github-corner:hover .octo-arm{animation:octocat-wave 560ms ease-in-out}@keyframes octocat-wave{0%,100%{transform:rotate(0)}20%,60%{transform:rotate(-25deg)}40%,80%{transform:rotate(10deg)}}@media (max-width:500px){.github-corner:hover .octo-arm{animation:none}.github-corner .octo-arm{animation:octocat-wave 560ms ease-in-out}}</style>
            
          
!

CSS

            
              $color-background: #7ca256;
$color-background-dark: darken(#7ca256, 1%);
$color-snake: #212121;

html, body
{
	width: 100%;
	height: 100%;
	margin: 0;
	padding: 0;
	background: #d2e0d2;
	overflow: hidden;
	
	
}

@import url('https://fonts.googleapis.com/css?family=VT323');

$tilt-amount: 10deg;
$shine-move: 40px;
$snake-lift: 30px;

h1
{
	margin: 0;
}

#container
{
	
	
    display: flex;
	flex-direction: column;
    align-items: center;
  	justify-content: center;
	margin: 0;
	padding: 0;
	height: 100%;
    width: 100%;
    text-transform: uppercase;
	font-family: 'VT323', monospace;

	perspective: 1000px;
	

	#board-container
	{
		
		border-radius: 8px;
		margin: 20px;
		padding: 20px 20px 10px 20px;
		//box-shadow: 9px 7px 30px -6px rgba(0,0,0,0.25);
		box-shadow: 0 2px 3px rgba(0, 0, 0, 0.1);
		background-color: white;
		background-image: radial-gradient(farthest-corner at 10px 10px, $color-background 0%, $color-background-dark 100%);
		transform: rotateX(0deg);
		transform-style: preserve-3d;
		transition: transform 0.3s ease, box-shadow 0.5s ease;
		//overflow: hidden;

		#board
		{
			border-radius: 5px;
			border: solid 1px $color-snake;
			transform: translateZ($snake-lift);
		}

		.shine-container
		{
			position: absolute;
			top: 0; 
			left: 0;
			right: 0; 
			bottom: 0;
			border-radius: 8px;
			overflow: hidden;

			.shine
			{
				position: absolute;
				top: -$shine-move; 
				left: -$shine-move;
				right: -$shine-move; 
				bottom: -$shine-move;
				background: linear-gradient(45deg, rgba(255,255,255,.75) 0%,rgba(255,255,255,0) 60%);
				transition: transform 0.3s ease;
			}
		}

		.info-container
		{
			height: 100%;
			width: 100%;
			min-height: 50px;
			margin-top: 5px;
			display: flex;
			flex-direction: row;
			//align-items: center;
			align-content: center;
			justify-content: space-between;
			transform: translateZ(20px);

			.label
			{
				margin: 5px 5px 0 0;
			}

			#score
			{
				font-size: 1.5em;
				font-weight: 300;
				padding: 10px 20px;
			}

			.flex
			{
				flex: 1;
			}
		}
	}

	&.PLAYING
	{
		#board-container
		{
			box-shadow: 0 45px 100px rgba(0, 0, 0, 0.3);
			transform: translateZ(40px);

			&.up
			{ 
				transform: rotateX($tilt-amount); 
				.shine-container .shine { transform: rotateX($tilt-amount) translateX(-$shine-move) translateZ(1px) } 
			}
			&.down
			{ 
				transform: rotateX(-$tilt-amount); 
				.shine-container .shine { transform: rotateX(-$tilt-amount) translateX($shine-move) translateZ(1px) } 
			}
			&.left
			{ 
				transform: rotateY(-$tilt-amount); 
				.shine-container .shine { transform: rotateY(-$tilt-amount) translateY(-$shine-move) translateZ(1px) } 
			}
			&.right
			{ 
				transform: rotateY($tilt-amount); 
				.shine-container .shine { transform: rotateY($tilt-amount) translateY($shine-move) translateZ(1px) } 
			}
		}
	}

	#start-button
	{
		font-family: inherit;
		text-transform: uppercase;
		font-size: 1.5em;
		background-color: transparent;
		color: $color-snake;
		padding: 10px 20px;
		//border: 2px solid $color-snake;
		border: 0;
		border-radius: 2px;
		//margin: 10px 10px 40px 10px;
		cursor: pointer;
		outline: none;

		&:hover
		{
			color: white;
		//	background-color: $color-background;
			border-color: $color-background;
		}
	}

	.state-driven
	{
		display: none;
	}

	&.READY
	{
		#start-button
		{
			display: block;
		}
	}

	&.ENDED
	{
		#start-button
		{
			display: block;
		}

		.re
		{
			display: inline;
		}
	}

	.controls
	{
		.keyboard{ display: inline; }
		.touch{ display: none; }

		@media (any-hover: none) and (any-pointer: coarse) 
		{ 
			.keyboard{ display: none; }
			.touch{ display: inline; }
		}

	}
}

@keyframes flash 
{
    0% { opacity: 1 }
    50% { opacity: 0 }
}

#board 
{
	--grid-columns: 0;
	--grid-rows: 0;
    --grid-size: 0;

    width: calc(var(--grid-size) * var(--grid-columns) * 1px);
    height: calc(var(--grid-size) * var(--grid-rows) * 1px);
	display: grid;
	grid-template-columns: repeat(var(--grid-columns), 1fr);
 	grid-template-rows: repeat(var(--grid-rows), 1fr);
    grid-gap: 1px;
    
	>div
	{
        background-color: transparent;

        &.food, &.snake
        {
            box-shadow: 0px 0px 0px rgba(0,0,0,0.1);
            transition: box-shadow 0.3s ease;
        }

        &.food
        {
            background-color: $color-snake;
            border-radius: 50%;
            margin: 1px;
        }
        
        &.snake
        {
            background-color: $color-snake;

            &.head
            {
                &.up{ border-top-left-radius: 50%; border-top-right-radius: 50%;}
                &.down{ border-bottom-left-radius: 50%; border-bottom-right-radius: 50%;}
                &.left{ border-top-left-radius: 50%; border-bottom-left-radius: 50%;}
                &.right{ border-top-right-radius: 50%; border-bottom-right-radius: 50%;}
            }

            &.tail
            {
                &.up{ border-bottom-left-radius: 50% 100%; border-bottom-right-radius: 50% 100%;}
                &.down{ border-top-left-radius: 50% 100%; border-top-right-radius: 50% 100%;}
                &.right{ border-bottom-left-radius: 100% 50%; border-top-left-radius: 100% 50%;}
                &.left{ border-bottom-right-radius: 100% 50%; border-top-right-radius: 100% 50%;}
            }

            &.turn-left
            {
                &.up{ border-top-right-radius: 50%;}
                &.down{ border-bottom-right-radius: 50%;}
            }
            
            &.turn-right
            {
                &.up{ border-top-left-radius: 50%;}
                &.down{ border-bottom-left-radius: 50%;}
            }
            
            &.turn-up
            {
                &.left{ border-bottom-left-radius: 50%;}
                &.right{ border-bottom-right-radius: 50%;}
            }
            
            &.turn-down
            {
                &.left{ border-top-left-radius: 50%;}
                &.right{ border-top-right-radius: 50%;}
            }

            &.dead
            {
                animation: flash 0.3s steps(1) infinite;
            }
        }  
	}
}

$snake-shadow: 5px;

.up #board >div
{
    &.food, &.snake { box-shadow: 0px $snake-shadow 0px 0px rgba(0,0,0,0.1);}
}

.down #board >div
{
    &.food, &.snake { box-shadow: 0px (-$snake-shadow) 0px 0px rgba(0,0,0,0.1);}
}

.left #board >div
{
    &.food, &.snake { box-shadow: $snake-shadow 0px 0px 0px rgba(0,0,0,0.1);}
}

.right #board >div
{
    &.food, &.snake { box-shadow: -$snake-shadow 0px 0px 0px rgba(0,0,0,0.1);}
}

            
          
!

JS

            
              

// Also on Github with Webpack and better Typescript support
// https://github.com/ste-vg/snake



console.clear();

enum GAME_STATES
{
	ready = 'READY',
	playing = 'PLAYING',
	ended = 'ENDED',
	paused = 'PAUSED'
}

enum SOUND
{
	move = 'move',
	dead = 'dead',
	collect = 'collect',
	start = 'start'
}

interface Direction
{
    name: string;
    x: number;
    y: number;
}

interface Position
{
    x: number;
    y: number;
}

interface SnakePart
{
    position: Position;
    direction: Direction;
}

interface States
{
    direction: Direction;
    nextDirection: Direction[];
    speed: number;
    game: string;
    timeStamp: number;
    snakeLength: number;
    score: number;
}

class App
{
    private game:Snake;
    private score:HTMLElement;
    private container:HTMLElement;
    private boardContainer:HTMLElement;
    private gameState:string;

    constructor()
    {  
        this.setupUI();
        this.setupGame();
    }

    setupUI()
    {
        this.score = document.getElementById('score');
        this.container = document.getElementById('container');
        this.boardContainer = document.getElementById('board-container');
        let startButton = Rx.Observable.fromEvent(document.getElementById('start-button'), 'click');
        startButton.subscribe((e:MouseEvent) => { console.log('click'); this.startGame(); })
    }

    setupGame()
    {
        let board = document.getElementById('board');

        this.game = new Snake(board);
        this.game.score.subscribe((score:number) => this.score.innerHTML = String(score));
        this.game.state.subscribe((state:string) => 
        {
            this.gameState = state;
            this.container.setAttribute('class', state)
        })
        this.game.direction.subscribe((direction:string) => this.boardContainer.setAttribute('class', direction))
        this.game.reset();
    }

    startGame()
    {
        if(this.gameState == GAME_STATES.ready || this.gameState == GAME_STATES.ended)
        {
            this.game.start();
        }
    }
}

class Snake
{
	private SETTINGS = {
		grid: {size: 10, rows: 20, columns: 28},
		game: {scoreIncrement: 10},
		snake: {startLength: 3, startSpeed: 300, speedIncrement: 10, minSpeed: 100, growBy: 2}
	}

	private DIRECTION = {
		up: 	{name: 'up', 	x: 0, 	y: -1},
		down: 	{name: 'down', 	x: 0, 	y: 1},
		left: 	{name: 'left', 	x: -1, 	y: 0},
		right: 	{name: 'right', x: 1, 	y: 0},
	}

	private states:States = {
		direction: this.DIRECTION.up,
		nextDirection: [this.DIRECTION.up],
		speed: 0,
		game: GAME_STATES.ready,
		timeStamp: 0,
		snakeLength: 0,
		score: 0
	}

	//http://loov.io/jsfx

	private sfxLibrary:any = {
		"start":{
			"Frequency":{"Start":463.2977575242697,"Slide":0.4268311992714056,"RepeatSpeed":0.6870767779635416},
			"Generator":{"A":0.015696072909390766},
			"Volume":{"Sustain":0.11353385475559997,"Decay":0.15242709930669884}
		},
		"collect1":{
			"Frequency":{"Start":1183.9224793246758,"ChangeSpeed":0.12793431035602038,"ChangeAmount":4.8612434857196085},
			"Volume":{"Sustain":0.011448880380128946,"Decay":0.3895997546965799,"Punch":0.4554389528366015}
		},
		"collect2":{
			"Frequency":{"Start":1070.9337014976563,"ChangeSpeed":0.1375978771153015,"ChangeAmount":5.9409661118536246},
			"Volume":{"Sustain":0.04890791064198004,"Decay":0.3415421194668815,"Punch":0.46291381941601983}
		},
		"dead":{
			"Frequency":{"Start":194.70758491034655,"Slide":-0.011628522004559189,"ChangeSpeed":0.6591296059731018,"ChangeAmount":2.6287197798189297},
			"Generator":{"Func":"noise"},
			"Volume":{"Sustain":0.17655222296084297,"Decay":0.24077933399701645,"Punch":0.6485369099751499}
		},
		"move1":{
			"Frequency":{"Start":452,"Slide":-0.04,"Min":30,"DeltaSlide":-0.05},
			"Generator":{"Func":"sine","A":0.08999657142884616,"ASlide":0.3390436675524937},
			"Filter":{"HP":0.10068425608105215},
			"Volume":{"Sustain":0,"Decay":0.041,"Attack":0.011,"Punch":0.04,"Master":0.18}
		},
		"move2":{
			"Frequency":{"Start":452,"Slide":-0.01,"Min":30,"DeltaSlide":-0.05},
			"Generator":{"Func":"sine","A":0.08999657142884616,"ASlide":0.3390436675524937},
			"Filter":{"HP":0.26,"LPResonance":0,"HPSlide":0.35,"LPSlide":0.51,"LP":1},
			"Volume":{"Sustain":0.02,"Decay":0.001,"Attack":0.021,"Punch":0.05,"Master":0.18},
			"Phaser":{"Offset":-0.03,"Sweep":-0.02},
			"Vibrato":{"FrequencySlide":0.04,"Frequency":14.01,"Depth":0.06}
		},
		"move3":{
			"Frequency":{"Start":452,"Slide":-0.01,"Min":30,"DeltaSlide":-0.05},
			"Generator":{"Func":"sine","A":0.08999657142884616,"ASlide":0.3390436675524937},
			"Filter":{"HP":0.26,"LPResonance":0,"HPSlide":0.35,"LPSlide":0.51,"LP":1},
			"Volume":{"Sustain":0.02,"Decay":0.001,"Attack":0.021,"Punch":0.05,"Master":0.18},
			"Phaser":{"Offset":-0.03,"Sweep":-0.02},
			"Vibrato":{"FrequencySlide":0.04,"Frequency":14.01,"Depth":0.16}
		},
		"move4":{
			"Frequency":{"Start":452,"Slide":-0.01,"Min":30,"DeltaSlide":-0.05},
			"Generator":{"Func":"sine","A":0.08999657142884616,"ASlide":0.3390436675524937},
			"Filter":{"HP":0.26,"LPResonance":0,"HPSlide":0.35,"LPSlide":0.51,"LP":1},
			"Volume":{"Sustain":0.02,"Decay":0.001,"Attack":0.021,"Punch":0.05,"Master":0.18},
			"Phaser":{"Offset":-0.03,"Sweep":-0.02},
			"Vibrato":{"FrequencySlide":0.04,"Frequency":14.01,"Depth":0.27}
		}
	}

	private player:any = jsfx.Sounds(this.sfxLibrary);

	private sounds:any = {
		collect: ['collect1', 'collect2'],
		dead: ['dead'],
		start: ['start'],
		move: ['move1', 'move2', 'move3', 'move4']
	}

	private board:HTMLElement;
	private grid:HTMLElement[] = [];
	private snake:SnakePart[] = [];
	private food:Position;
	private touchStartPosition:Position;

	// subjects

	public state:Subject<string> = new Rx.Subject();
	public score:Subject<number> = new Rx.Subject();
	public direction:Subject<string> = new Rx.Subject();

	// observables

	private keyPress:Observable<any>;
	private input:Input;

	// subscriptions
	private keyPressSubscription:Subscription;
	private touchStartSubscription:Subscription;
	private touchEndSubscription:Subscription;
	private keyRestartSubscription:Subscription;

	constructor(boardElement: HTMLElement)
	{
		this.board = boardElement;
		
		// setup the game board grid
		
		this.board.style.setProperty("--grid-size", String(this.SETTINGS.grid.size));
		this.board.style.setProperty("--grid-columns", String(this.SETTINGS.grid.columns));
		this.board.style.setProperty("--grid-rows", String(this.SETTINGS.grid.rows));
		
		let count = this.SETTINGS.grid.columns * this.SETTINGS.grid.rows;
		for(let i = 0; i < count; i++)
		{
			let sq = document.createElement("div");
			this.grid.push(sq);
			this.board.appendChild(sq);
		}

		// setup observables

		this.input = new Input(document.body);
	
		this.keyPress = Rx.Observable.fromEvent(document, "keydown")
			.filter((e:KeyboardEvent) => ['arrowright', 'arrowleft', 'arrowup', 'arrowdown'].indexOf(e.key.toLowerCase()) >= 0)
			.map((e:KeyboardEvent) => 
			{
				e.preventDefault();
				return e.key.toLowerCase().replace('arrow','')
			})

		let onEnter = Rx.Observable.fromEvent(document, "keydown")
			.filter((e:KeyboardEvent) => ['enter'].indexOf(e.key.toLowerCase()) >= 0)
				
		this.touchStartSubscription = this.input.starts.subscribe((position:Position) => {
			this.touchStartPosition = position;
		})

		this.touchEndSubscription = this.input.ends.subscribe((position:Position) => 
		{
			let hDiff = this.touchStartPosition.x - position.x;	
			let hDiffAbs = Math.abs(hDiff);	
			let vDiff = this.touchStartPosition.y - position.y;
			let vDiffAbs = Math.abs(vDiff);
			
			if(hDiffAbs > 10 || vDiffAbs > 10)
			{
				if(hDiffAbs > vDiffAbs)
				{
					if(hDiff < 0) this.setDirection(this.DIRECTION['right']);
					else this.setDirection(this.DIRECTION['left']);
				}
				else
				{
					if(vDiff < 0) this.setDirection(this.DIRECTION['down']);
					else this.setDirection(this.DIRECTION['up']);
				}
			}
		})			

		this.keyPressSubscription = this.keyPress.subscribe((key: string) => 
		{
			if(this.states.game == GAME_STATES.playing)
			{
				this.setDirection(this.DIRECTION[key])
			}
		})

		this.keyRestartSubscription = onEnter.subscribe(e => this.start())
	}

	private playSound(type:SOUND)
	{
		let options = this.sounds[type];
		let selected = options[Math.floor(Math.random() * options.length)];
		this.player[selected]();
	}
	
	private checkDirection(setDirection:Direction, newDirection:Direction):boolean
	{
		return setDirection.x != newDirection.x && setDirection.y != newDirection.y;	
	}

	private setDirection(direction:Direction)
	{
		let queueable:boolean = false;

		if(this.states.direction.name != this.states.nextDirection[0].name)
		{
			//if a valid move we could queue this move
			if(this.states.nextDirection.length == 1 && this.checkDirection(this.states.nextDirection[0], direction))
			{
				queueable = true;
			}
		}

		if(queueable && this.checkDirection(this.states.nextDirection[0], direction)) 
		{
			this.states.nextDirection.push(direction);
			this.playSound(SOUND.move);
		}
		else if(this.checkDirection(this.states.direction, direction)) 
		{
			this.states.nextDirection = [direction];
			this.playSound(SOUND.move);
		}
	}

	public reset()
	{
		this.updateGameState(GAME_STATES.ready);

		this.snake = []
		this.states.direction = this.DIRECTION.up;
		this.states.nextDirection = [this.DIRECTION.up];
		this.states.snakeLength = this.SETTINGS.snake.startLength;
		this.updateScore(0);
		let center:Position = {x: Math.round(this.SETTINGS.grid.columns / 2), y: Math.round(this.SETTINGS.grid.rows / 2)};

		for(let i = 0; i < this.states.snakeLength; i++)
		{
			let snakePart:SnakePart = {
				position: {x: center.x, y: center.y + (i * 1)},
				direction: this.DIRECTION.up
			}

			this.snake.unshift(snakePart);
		}

		this.placeFood();

		this.draw();
	}

	private draw()
	{
		// reset all sqaures
		for(let i = 0; i < this.grid.length; i++) this.grid[i].className = '';

		// set snake squares
		for(let i = 0; i < this.snake.length; i++)
		{
			let classes = ['snake'];
			if(this.states.game == GAME_STATES.ended) classes.push('dead');
			if(i == 0) classes.push('tail');
			if(i == this.snake.length - 1) classes.push('head');
			let snakePart = this.snake[i];
			let nextSnakePart = this.snake[i + 1] ? this.snake[i + 1] : null;
			
			if(nextSnakePart && snakePart.direction.name != nextSnakePart.direction.name)
			{
				classes.push('turn-' + nextSnakePart.direction.name)
			}
			
			if(i == 0 && nextSnakePart)
			{
				classes.push(nextSnakePart.direction.name);
			}
			else
			{
				classes.push(snakePart.direction.name);
			}
			let gridIndex = this.getIndexFromPosition(snakePart.position);
			this.grid[gridIndex].className = classes.join(' ');
		}

		// set food sqaure

		let foodSquare = this.grid[this.getIndexFromPosition(this.food)];
		foodSquare.className = 'food';
	}

	private getIndexFromPosition(position:Position):number
	{
		return position.x + (position.y * this.SETTINGS.grid.columns);
	}

	private getPositionFromIndex(index:number):Position
	{
		let y = Math.floor(index / this.SETTINGS.grid.columns);
		let x = Math.floor(index % this.SETTINGS.grid.columns);
		return {x: x, y: y};
	}

	private eatFood()
	{
		this.addScore();
		this.playSound(SOUND.collect);
		this.states.snakeLength += this.SETTINGS.snake.growBy;
		this.states.speed -= this.SETTINGS.snake.speedIncrement;
		if(this.states.speed < this.SETTINGS.snake.minSpeed) this.states.speed = this.SETTINGS.snake.minSpeed;
		this.placeFood();
		
	}

	private updateGameState(newState:string)
	{
		this.states.game = newState;
		this.state.next(this.states.game);
	}

	private addScore()
	{
		this.updateScore(this.states.score + this.SETTINGS.game.scoreIncrement);
	}
	
	private updateScore(newScore:number)
	{
		this.states.score = newScore;
		this.score.next(this.states.score);
	}

	private placeFood()
	{
		let takenSpaces: number[] = [];
		for(let i = 0; i < this.snake.length; i++)
		{
			let index = this.getIndexFromPosition(this.snake[i].position);
			takenSpaces.push(index);
		}

		let availableSpaces: number[] = [];
		for(let i = 0; i < this.grid.length; i++)
		{
			if(takenSpaces.indexOf(i) < 0) availableSpaces.push(i);
		}

		let i = Math.floor(Math.random() * availableSpaces.length);
		this.food = this.getPositionFromIndex(availableSpaces[i]);
	}

	private tick(timeStamp:number)
	{
		if(this.states.game == GAME_STATES.playing)
		{
			if(!this.states.timeStamp || (timeStamp - this.states.timeStamp) > this.states.speed)
			{
				this.states.timeStamp = timeStamp;
				if(this.states.nextDirection.length > 1)
				{
					this.states.direction = this.states.nextDirection.shift();
				}
				else
				{
					this.states.direction = this.states.nextDirection[0];
				}
				this.direction.next(this.states.nextDirection[this.states.nextDirection.length - 1].name);

				let snakeHead = this.snake[this.snake.length - 1];
				let newPosition:Position = {
					x: snakeHead.position.x + this.states.direction.x,
					y: snakeHead.position.y + this.states.direction.y
				}

				// end the game if the new postion is out of bounds

				if(	newPosition.x < 0 || 
					newPosition.x > this.SETTINGS.grid.columns - 1 || 
					newPosition.y < 0 || 
					newPosition.y > this.SETTINGS.grid.rows - 1)
				{
					return this.end();
				}

				// end the game if the new position is already taken by snake

				for(let i = 0; i < this.snake.length; i++)
				{
					if(this.snake[i].position.x == newPosition.x && this.snake[i].position.y == newPosition.y)
					{
						return this.end();
					}
				}

				// all good to proceed with new snake head

				let newSnakeHead:SnakePart = {
					position: newPosition,
					direction: this.DIRECTION[this.states.direction.name]
				}
				this.snake.push(newSnakeHead);

				while(this.snake.length > this.states.snakeLength)
				{
					this.snake.shift();
				}

				// check if head is on food

				if(newSnakeHead.position.x == this.food.x && newSnakeHead.position.y == this.food.y)
				{
					this.eatFood();
				}

				this.draw();
			}

			window.requestAnimationFrame(time => this.tick(time));
		}
	}

	public start()
	{
		this.reset();
		this.playSound(SOUND.start);
		this.states.speed = this.SETTINGS.snake.startSpeed;
		this.updateGameState(GAME_STATES.playing);
		this.tick(0);
		window.focus();
	}

	private end()
	{
		console.warn('GAME OVER')
		this.playSound(SOUND.dead);
		this.updateGameState(GAME_STATES.ended);
		this.direction.next('');
		this.draw();
	}
}

// touch & mouse input code form https://codepen.io/HunorMarton/post/handling-complex-mouse-and-touch-events-with-rxjs

class Input
{
    private mouseDowns:Observable<Position>;
    private mouseMoves:Observable<Position>;
    private mouseUps:Observable<Position>;

    private touchStarts:Observable<Position>;
    private touchMoves:Observable<Position>;
    private touchEnds:Observable<Position>;

    public starts:Observable<Position>;
    public moves:Observable<Position>;
    public ends:Observable<Position>;

    constructor(element:HTMLElement)
    {
        this.mouseDowns = Rx.Observable.fromEvent(element, "mousedown").map(this.mouseEventToCoordinate);
        this.mouseMoves = Rx.Observable.fromEvent(window, "mousemove").map(this.mouseEventToCoordinate);
        this.mouseUps = Rx.Observable.fromEvent(window, "mouseup").map(this.mouseEventToCoordinate);

        this.touchStarts = Rx.Observable.fromEvent(element, "touchstart").map(this.touchEventToCoordinate);
        this.touchMoves = Rx.Observable.fromEvent(element, "touchmove").map(this.touchEventToCoordinate);
        this.touchEnds = Rx.Observable.fromEvent(window, "touchend").map(this.touchEventToCoordinate);

        this.starts = this.mouseDowns.merge(this.touchStarts);
        this.moves = this.mouseMoves.merge(this.touchMoves);
        this.ends = this.mouseUps.merge(this.touchEnds);
    }

    private mouseEventToCoordinate = (mouseEvent:MouseEvent) => 
    {
        mouseEvent.preventDefault();
        return {
            x: mouseEvent.clientX, 
            y: mouseEvent.clientY
        };
    };

    private touchEventToCoordinate = (touchEvent:TouchEvent) => 
    {
        //touchEvent.preventDefault();
        return {
            x: touchEvent.changedTouches[0].clientX, 
            y: touchEvent.changedTouches[0].clientY
        };
    };
}

let app = new App();
            
          
!
999px

Console