110 lines
2.4 KiB
HTML
110 lines
2.4 KiB
HTML
<!DOCTYPE html>
|
|
<html>
|
|
<head>
|
|
<meta charset="utf-8" />
|
|
<title>MDN Breakout</title>
|
|
<style>
|
|
* { padding: 0; margin: 0; }
|
|
canvas { background: #eee; display: block; margin: 0 auto; }
|
|
</style>
|
|
</head>
|
|
<body>
|
|
<canvas id="myCanvas" width="480" height="320"></canvas>
|
|
<script>
|
|
(function() {
|
|
var canvas = document.getElementById("myCanvas");
|
|
var ctx = canvas.getContext("2d");
|
|
var ballRadius = 10;
|
|
var ballColor = '#0095DD';
|
|
var paddleHeight = 10;
|
|
var paddleWidth = 75;
|
|
var paddleX = (canvas.width-paddleWidth)/2;
|
|
var paddleSpeed = 7;
|
|
var rightPressed = false;
|
|
var leftPressed = false;
|
|
var x = canvas.width/2;
|
|
var y = canvas.height-30;
|
|
var dx = 2;
|
|
var dy = -2;
|
|
|
|
function randInt(min, max) {
|
|
min = Math.ceil(min);
|
|
max = Math.floor(max);
|
|
return Math.floor(Math.random() * (max - min)) + min;
|
|
}
|
|
|
|
function randColor() {
|
|
return 'rgba(' + ([
|
|
randInt(0, 255),
|
|
randInt(0, 255),
|
|
randInt(0, 255)
|
|
].map(function(elem, i) { return '' + elem; }).join(',')) + ', 1.0)'
|
|
}
|
|
|
|
function drawBall() {
|
|
ctx.beginPath();
|
|
ctx.arc(x, y, ballRadius, 0, Math.PI*2);
|
|
ctx.fillStyle = ballColor;
|
|
ctx.fill();
|
|
ctx.closePath();
|
|
}
|
|
|
|
function drawPaddle() {
|
|
ctx.beginPath();
|
|
ctx.rect(paddleX, canvas.height-paddleHeight, paddleWidth, paddleHeight);
|
|
ctx.fillStyle = "#0095DD";
|
|
ctx.fill();
|
|
ctx.closePath();
|
|
}
|
|
|
|
function draw() {
|
|
ctx.clearRect(0, 0, canvas.width, canvas.height);
|
|
drawBall();
|
|
drawPaddle();
|
|
|
|
if(x + dx > canvas.width-ballRadius || x + dx < ballRadius) {
|
|
dx = -dx;
|
|
ballColor = randColor();
|
|
}
|
|
if(y + dy > canvas.height-ballRadius || y + dy < ballRadius) {
|
|
dy = -dy;
|
|
ballColor = randColor();
|
|
}
|
|
|
|
if(rightPressed && paddleX < canvas.width-paddleWidth) {
|
|
paddleX += paddleSpeed;
|
|
}
|
|
else if(leftPressed && paddleX > 0) {
|
|
paddleX -= paddleSpeed;
|
|
}
|
|
|
|
x += dx;
|
|
y += dy;
|
|
}
|
|
|
|
function keyDownHandler(e) {
|
|
if(e.keyCode == 39) {
|
|
rightPressed = true;
|
|
}
|
|
else if(e.keyCode == 37) {
|
|
leftPressed = true;
|
|
}
|
|
}
|
|
|
|
function keyUpHandler(e) {
|
|
if(e.keyCode == 39) {
|
|
rightPressed = false;
|
|
}
|
|
else if(e.keyCode == 37) {
|
|
leftPressed = false;
|
|
}
|
|
}
|
|
|
|
document.addEventListener("keydown", keyDownHandler, false);
|
|
document.addEventListener("keyup", keyUpHandler, false);
|
|
setInterval(draw, 10);
|
|
})();
|
|
</script>
|
|
</body>
|
|
</html>
|