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<header class="wrap">
<h1>Snake</h1>
<p class="score">Score: <span id="score_value">0</span></p>
</header>
<canvas class="wrap" id="snake" width="320" height="320" tabindex="1"></canvas>
<!-- Game Over Screen -->
<div id="gameover">
<h2>Game Over</h2>
<p>press <span style="background-color: #FFFFFF; color: #000000">space</span> to begin a</p>
<a id="newgame_gameover">new game</a>
<a id="setting_gameover">settings</a>
</div>
<!-- Setting screen -->
<div id="setting">
<h2>Settings</h2>
<a id="newgame_setting">new game</a>
<p>Speed:
<input id="speed1" type="radio" name="speed" value="120" checked/>
<label for="speed1">Slow</label>
<input id="speed2" type="radio" name="speed" value="75"/>
<label for="speed2">Normal</label>
<input id="speed3" type="radio" name="speed" value="35"/>
<label for="speed3">Fast</label>
</p>
<p>Wall:
<input id="wallon" type="radio" name="wall" value="1" checked/>
<label for="wallon">On</label>
<input id="walloff" type="radio" name="wall" value="0"/>
<label for="walloff">Off</label>
</p>
</div>
<!-- Main Menu Screen -->
<div id="menu">
<h2>Snake</h2>
<a id="newgame_menu">new game</a>
<a id="setting_menu">settings</a>
</div>
<!--
<div id="debug" style="font-size: 16px; color: #FFF;"></div>
-->
@import url("https://fonts.googleapis.com/css?family=VT323");
::selection {color:#FFFFFF; background:transparent;}
::-moz-selection {color:#FFFFFF; background:transparent;}
*{
margin: 0;
padding: 0;
font-family: "VT323";
}
body{
background-color: #000000;
}
.wrap{
margin-left: auto;
margin-right: auto;
}
header{
width: 340px;
font-size: 0;
}
canvas{
display: none;
border-style: solid;
border-width: 10px;
border-color: #FFFFFF;
}
canvas:focus{
outline: none;
}
/* Top Styles */
h1{
display: inline-block;
width: 100px;
font-size: 32px;
color: #FFFFFF;
}
.score{
display: inline-block;
width: 240px;
font-size: 20px;
color: #FFFFFF;
text-align: right;
}
.score_value{
font-size: inherit;
}
/* All screens style */
#gameover a, #setting a, #menu a{
display: block;
}
#gameover a, #setting a:hover, #menu a:hover{
cursor: pointer;
}
#gameover a:hover::before, #setting a:hover::before, #menu a:hover::before{
content: ">";
margin-right: 10px;
}
/* Menu Screen Style */
#menu{
display: block;
width: 340px;
padding-top: 95px;
padding-bottom: 95px;
font-size: 40px;
margin-left: auto;
margin-right: auto;
text-align: center;
color: #FFF;
}
#menu h2{
-webkit-animation: logo-ani 1000ms linear infinite;
animation: logo-ani 1000ms linear infinite;
margin-bottom: 30px;
}
#menu a{
font-size: 30px;
}
@-webkit-keyframes logo-ani{
50%{-webkit-transform: scale(1.3,1.3);}
100%{-webkit-transform: scale(1.0,1.0);}
}
@keyframes logo-ani{
50%{transform: scale(1.3,1.3);}
100%{transform: scale(1.0,1.0);}
}
/* Game Over Screen Style */
#gameover{
display: none;
width: 340px;
padding-top: 95px;
padding-bottom: 95px;
margin-left: auto;
margin-right: auto;
text-align: center;
font-size: 30px;
color: #FFF;
}
#gameover p{
margin-top: 25px;
font-size: 20px;
}
/* Settings Screen Style */
#setting{
display: none;
width: 340px;
margin-left: auto;
margin-right: auto;
padding-top: 85px;
padding-bottom: 85px;
font-size: 30px;
color: #FFF;
text-align: center;
}
#setting h2{
margin-bottom: 15px;
}
#setting p{
margin-top: 10px;
}
#setting input{
display:none;
}
#setting label{
cursor: pointer;
}
#setting input:checked + label{
background-color: #FFF;
color: #000;
}
(function(){
/////////////////////////////////////////////////////////////
// Canvas & Context
var canvas;
var ctx;
// Snake
var snake;
var snake_dir;
var snake_next_dir;
var snake_speed;
// Food
var food = {x: 0, y: 0};
// Score
var score;
// Wall
var wall;
// HTML Elements
var screen_snake;
var screen_menu;
var screen_setting;
var screen_gameover;
var button_newgame_menu;
var button_newgame_setting;
var button_newgame_gameover;
var button_setting_menu;
var button_setting_gameover;
var ele_score;
var speed_setting;
var wall_setting;
/////////////////////////////////////////////////////////////
var activeDot = function(x, y){
ctx.fillStyle = "#FFFFFF";
ctx.fillRect(x * 10, y * 10, 10, 10);
}
/////////////////////////////////////////////////////////////
var changeDir = function(key){
if(key == 38 && snake_dir != 2){
snake_next_dir = 0;
}else{
if (key == 39 && snake_dir != 3){
snake_next_dir = 1;
}else{
if (key == 40 && snake_dir != 0){
snake_next_dir = 2;
}else{
if(key == 37 && snake_dir != 1){
snake_next_dir = 3;
} } } }
}
/////////////////////////////////////////////////////////////
var addFood = function(){
food.x = Math.floor(Math.random() * ((canvas.width / 10) - 1));
food.y = Math.floor(Math.random() * ((canvas.height / 10) - 1));
for(var i = 0; i < snake.length; i++){
if(checkBlock(food.x, food.y, snake[i].x, snake[i].y)){
addFood();
}
}
}
/////////////////////////////////////////////////////////////
var checkBlock = function(x, y, _x, _y){
return (x == _x && y == _y) ? true : false;
}
/////////////////////////////////////////////////////////////
var altScore = function(score_val){
ele_score.innerHTML = String(score_val);
}
/////////////////////////////////////////////////////////////
var mainLoop = function(){
var _x = snake[0].x;
var _y = snake[0].y;
snake_dir = snake_next_dir;
// 0 - Up, 1 - Right, 2 - Down, 3 - Left
switch(snake_dir){
case 0: _y--; break;
case 1: _x++; break;
case 2: _y++; break;
case 3: _x--; break;
}
snake.pop();
snake.unshift({x: _x, y: _y});
// --------------------
// Wall
if(wall == 1){
// On
if (snake[0].x < 0 || snake[0].x == canvas.width / 10 || snake[0].y < 0 || snake[0].y == canvas.height / 10){
showScreen(3);
return;
}
}else{
// Off
for(var i = 0, x = snake.length; i < x; i++){
if(snake[i].x < 0){
snake[i].x = snake[i].x + (canvas.width / 10);
}
if(snake[i].x == canvas.width / 10){
snake[i].x = snake[i].x - (canvas.width / 10);
}
if(snake[i].y < 0){
snake[i].y = snake[i].y + (canvas.height / 10);
}
if(snake[i].y == canvas.height / 10){
snake[i].y = snake[i].y - (canvas.height / 10);
}
}
}
// --------------------
// Autophagy death
for(var i = 1; i < snake.length; i++){
if (snake[0].x == snake[i].x && snake[0].y == snake[i].y){
showScreen(3);
return;
}
}
// --------------------
// Eat Food
if(checkBlock(snake[0].x, snake[0].y, food.x, food.y)){
snake[snake.length] = {x: snake[0].x, y: snake[0].y};
score += 1;
altScore(score);
addFood();
activeDot(food.x, food.y);
}
// --------------------
ctx.beginPath();
ctx.fillStyle = "#000000";
ctx.fillRect(0, 0, canvas.width, canvas.height);
// --------------------
for(var i = 0; i < snake.length; i++){
activeDot(snake[i].x, snake[i].y);
}
// --------------------
activeDot(food.x, food.y);
// Debug
//document.getElementById("debug").innerHTML = snake_dir + " " + snake_next_dir + " " + snake[0].x + " " + snake[0].y;
setTimeout(mainLoop, snake_speed);
}
/////////////////////////////////////////////////////////////
var newGame = function(){
showScreen(0);
screen_snake.focus();
snake = [];
for(var i = 4; i >= 0; i--){
snake.push({x: i, y: 15});
}
snake_next_dir = 1;
score = 0;
altScore(score);
addFood();
canvas.onkeydown = function(evt) {
evt = evt || window.event;
changeDir(evt.keyCode);
}
mainLoop();
}
/////////////////////////////////////////////////////////////
// Change the snake speed...
// 150 = slow
// 100 = normal
// 50 = fast
var setSnakeSpeed = function(speed_value){
snake_speed = speed_value;
}
/////////////////////////////////////////////////////////////
var setWall = function(wall_value){
wall = wall_value;
if(wall == 0){screen_snake.style.borderColor = "#606060";}
if(wall == 1){screen_snake.style.borderColor = "#FFFFFF";}
}
/////////////////////////////////////////////////////////////
// 0 for the game
// 1 for the main menu
// 2 for the settings screen
// 3 for the game over screen
var showScreen = function(screen_opt){
switch(screen_opt){
case 0: screen_snake.style.display = "block";
screen_menu.style.display = "none";
screen_setting.style.display = "none";
screen_gameover.style.display = "none";
break;
case 1: screen_snake.style.display = "none";
screen_menu.style.display = "block";
screen_setting.style.display = "none";
screen_gameover.style.display = "none";
break;
case 2: screen_snake.style.display = "none";
screen_menu.style.display = "none";
screen_setting.style.display = "block";
screen_gameover.style.display = "none";
break;
case 3: screen_snake.style.display = "none";
screen_menu.style.display = "none";
screen_setting.style.display = "none";
screen_gameover.style.display = "block";
break;
}
}
/////////////////////////////////////////////////////////////
window.onload = function(){
canvas = document.getElementById("snake");
ctx = canvas.getContext("2d");
// Screens
screen_snake = document.getElementById("snake");
screen_menu = document.getElementById("menu");
screen_gameover = document.getElementById("gameover");
screen_setting = document.getElementById("setting");
// Buttons
button_newgame_menu = document.getElementById("newgame_menu");
button_newgame_setting = document.getElementById("newgame_setting");
button_newgame_gameover = document.getElementById("newgame_gameover");
button_setting_menu = document.getElementById("setting_menu");
button_setting_gameover = document.getElementById("setting_gameover");
// etc
ele_score = document.getElementById("score_value");
speed_setting = document.getElementsByName("speed");
wall_setting = document.getElementsByName("wall");
// --------------------
button_newgame_menu.onclick = function(){newGame();};
button_newgame_gameover.onclick = function(){newGame();};
button_newgame_setting.onclick = function(){newGame();};
button_setting_menu.onclick = function(){showScreen(2);};
button_setting_gameover.onclick = function(){showScreen(2)};
setSnakeSpeed(150);
setWall(1);
showScreen("menu");
// --------------------
// Settings
// speed
for(var i = 0; i < speed_setting.length; i++){
speed_setting[i].addEventListener("click", function(){
for(var i = 0; i < speed_setting.length; i++){
if(speed_setting[i].checked){
setSnakeSpeed(speed_setting[i].value);
}
}
});
}
// wall
for(var i = 0; i < wall_setting.length; i++){
wall_setting[i].addEventListener("click", function(){
for(var i = 0; i < wall_setting.length; i++){
if(wall_setting[i].checked){
setWall(wall_setting[i].value);
}
}
});
}
document.onkeydown = function(evt){
if(screen_gameover.style.display == "block"){
evt = evt || window.event;
if(evt.keyCode == 32){
newGame();
}
}
}
}
})();
Also see: Tab Triggers