JavaScript实现流星雨效果
下面是实现流星雨效果的JavaScript代码示例：
HTML：
<!DOCTYPE html>
<html>
<head>
<title>流星雨效果</title>
<style>
body {
background: black;
overflow: hidden;
}
</style>
</head>
<body>
<canvas id="canvas"></canvas>
<script src="meteor.js"></script>
</body>
</html>
JavaScript：
// 定义画布
var canvas = document.getElementById('canvas');
var ctx = canvas.getContext('2d');
// 设置画布宽和高
var W = window.innerWidth;
var H = window.innerHeight;
canvas.width = W;
canvas.height = H;
// 定义流星数组
var meteors = [];
// 定义流星对象
var Meteor = function(x, y, speed) {
this.x = x;
this.y = y;
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