nokia-snake-game.html

<style>
  .game {
      background-color: #f0f0f0;
      border-radius: 10px;
      padding: 10px;
      max-width: 300px;
      margin: auto;
  }

  #snake {
    display: block;
    margin: 0 auto;
    background-color: #000;
    width: 85vw;
    max-width: 280px;
  }
</style

<div class="game">
    <canvas id="snake" height="240" />
</div>                

<script src="snake.js"></script>

snake.js

/**
* Truly hacked up javascript. I am sure you can make this better.
*/

var canvas = document.getElementById("snake");
var context = canvas.getContext("2d");

game = {
  
  score: 0,
  fps: 8,
  over: false,
  message: null,
  
  start: function() {
    game.over = false;
    game.message = null;
    game.score = 0;
    game.fps = 8;
    snake.init();
    food.set();
  },
  
  stop: function() {
    game.over = true;
    game.message = 'TAP TO PLAY';
  },
  
  drawBox: function(x, y, size, color) {
    context.fillStyle = color;
    context.beginPath();
    context.moveTo(x - (size / 2), y - (size / 2));
    context.lineTo(x + (size / 2), y - (size / 2));
    context.lineTo(x + (size / 2), y + (size / 2));
    context.lineTo(x - (size / 2), y + (size / 2));
    context.closePath();
    context.fill();
  },
  
  drawScore: function() {
    context.fillStyle = '#ddd';
    context.font = '36px Impact, Ariel, sans-serif';
    context.textAlign = 'center';
    context.fillText(game.score, canvas.width/2, canvas.height  * .9);
  },
  
  drawMessage: function() {
    if (game.message !== null) {
      context.fillStyle = '#fff';
      context.font = (canvas.height / 10) + 'px Impact, Ariel, sans-serif';
      context.textAlign = 'center';
      context.fillText(game.message, canvas.width/2, canvas.height/2);
    }
  },
  
  resetCanvas: function() {
    context.clearRect(0, 0, canvas.width, canvas.height);
  }
  
};

snake = {  
  size: canvas.width / 40,
  x: null,
  y: null,
  color: '#0F0',
  direction: 'left',
  sections: [],
  
  init: function() {
    snake.sections = [];
    snake.direction = 'left';
    snake.x = canvas.width / 2 + snake.size / 2;
    snake.y = canvas.height /2 + snake.size / 2;
    for (i = snake.x + (5 * snake.size); i >= snake.x; i-=snake.size) {
      snake.sections.push(i + ',' + snake.y); 
    }
  },
  
  move: function() {
    switch(snake.direction) {
      case 'up':
        snake.y-=snake.size;
        break;
      case 'down':
        snake.y+=snake.size;
        break;
      case 'left':
        snake.x-=snake.size;
        break;
      case 'right':
        snake.x+=snake.size;
        break;
    }
    snake.checkCollision();
    snake.checkGrowth();
    snake.sections.push(snake.x + ',' + snake.y);
  },
  
  draw: function() {
    for (i = 0; i < snake.sections.length; i++) {
      snake.drawSection(snake.sections[i].split(','));
    }    
  },
  
  drawSection: function(section) {
    game.drawBox(parseInt(section[0]), parseInt(section[1]), snake.size, snake.color);
  },
  
  checkCollision: function() {
    if (snake.isCollision(snake.x, snake.y) === true) {
      game.stop();
    }
  },
  
  isCollision: function(x, y) {
    if (x < snake.size/2 ||
        x > canvas.width ||
        y < snake.size/2 ||
        y > canvas.height ||
        snake.sections.indexOf(x+','+y) >= 0) {
      return true;
    }
  },
  
  checkGrowth: function() {
    if (snake.x == food.x && snake.y == food.y) {
      game.score++;
      if (game.score % 5 == 0 && game.fps < 60) {
        game.fps++;
      }
      food.set();
    } else {
      snake.sections.shift();
    }
  }
  
};

food = {
  size: null,
  x: null,
  y: null,
  color: '#0f0',
  
  set: function() {
    food.size = snake.size;
    food.x = (Math.ceil(Math.random() * 10) * snake.size * 4) - snake.size / 2;
    food.y = (Math.ceil(Math.random() * 10) * snake.size * 3) - snake.size / 2;
  },
  
  draw: function() {
    game.drawBox(food.x, food.y, food.size, food.color);
  }  
};

inverseDirection = {
  'up':'down',
  'left':'right',
  'right':'left',
  'down':'up'
};

keys = {
  up: [38, 75, 87],
  down: [40, 74, 83],
  left: [37, 65, 72],
  right: [39, 68, 76],
  start_game: [13, 32]
};

Object.prototype.getKey = function(value){
  for(var key in this){
    if(this[key] instanceof Array && this[key].indexOf(value) >= 0){
      return key;
    }
  }
  return null;
};

            
function isTouchDevice() {
    if ("ontouchstart" in document.documentElement) {
        return true;
    } else {
        return false;
    }            
}
        
if (isTouchDevice()) {    
    addEventListener("touchstart", handleEvent, false);    
} else {
    addEventListener("keydown", function (e) {
        lastKey = keys.getKey(e.keyCode);
        if (['up', 'down', 'left', 'right'].indexOf(lastKey) >= 0
            && lastKey != inverseDirection[snake.direction]) {
          snake.direction = lastKey;
        } else if (['start_game'].indexOf(lastKey) >= 0 && game.over) {
          game.start();
        }
    }, false);    
    addEventListener("click", handleEvent, false);    
}
        
        
function handleEvent(e) {
    e.stopPropagation(); 
    
    if (game.over) {
        game.start();        
    }    
    if (snake.direction == 'left')
        snake.direction = 'down';
    else if (snake.direction == 'down')
        snake.direction = 'right';
    else if (snake.direction == 'right')
        snake.direction = 'up';
    else if (snake.direction == 'up')
        snake.direction = 'left';
}        
        
        
var requestAnimationFrame =  requestAnimationFrame ||
      webkitRequestAnimationFrame ||
      mozRequestAnimationFrame ||
      msRequestAnimationFrame ||
      oRequestAnimationFrame;

function loop() {
  if (game.over == false) {
    game.resetCanvas();
    game.drawScore();
    snake.move();
    food.draw();
    snake.draw();
    game.drawMessage();
  }
  setTimeout(function() {
    requestAnimationFrame(loop);
  }, 1000 / game.fps);
};

requestAnimationFrame(loop);    

Thanks for the nice Snake Game

Thanks for the nice Snake Game

Glad you liked it!