雨夹雪背景特效
在这暖暖的冬天，给自己的网站加点雪花特效简直美滋滋啊。
来给生活比个样！
效果图：
实现代码：
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>冬雪</title>
</head>
<body style="width: 100%;height: 100%;background:#add8e6;">
</body>
</html>
<script>
class Snow {
constructor (opt = {}) {
// 是否是雨
this.isRain = opt.isRain || false
// 元素
this.el = null
// 倾斜方向
this.dir = opt.dir || 'r'
// 直径
this.width = 0
// 最大直径
this.maxWidth = opt.maxWidth || 80
// 最小直径
this.minWidth = opt.minWidth || 2
// 透明度
this.opacity = 0
// 水平位置
this.x = 0
// 重置位置
this.y = 0
// z轴位置
this.z = 0
// 水平速度
this.sx = 0
// 是否左右摇摆
this.isSwing = false
// 左右摇摆的步长
this.stepSx = 0.02
// 左右摇摆的正弦函数x变量
this.swingRadian = 1
// 左右摇摆的正弦x步长
this.swingStep = 0.01
// 垂直速度
this.sy = 0
// 最大速度
this.maxSpeed = opt.maxSpeed || 4
// 最小速度
this.minSpeed = opt.minSpeed || 1
// 快速划过的最大速度
this.quickMaxSpeed = opt.quickMaxSpeed || 10
// 快速划过的最小速度
this.quickMinSpeed = opt.quickMinSpeed || 8
// 快速划过的宽度
this.quickWidth = opt.quickWidth || 80
// 快速划过的透明度
this.quickOpacity = opt.quickOpacity || 0.2
// 窗口尺寸
this.windowWidth = window.innerWidth
this.windowHeight = window.innerHeight
this.init()
}
// 随机初始化属性
init (reset) {
let isQuick = Math.random() > 0.8
this.isSwing = Math.random() > 0.8
this.width = isQuick ? this.quickWidth : Math.floor(Math.random() * this.maxWidth + this.minWidth)
this.opacity = isQuick ? this.quickOpacity : Math.random()
this.x = Math.floor(Math.random() * (this.windowWidth - this.width))
this.y = Math.floor(Math.random() * (this.windowHeight - this.width))
if (reset && Math.random() > 0.8) {
this.x = -this.width
} else if (reset) {
this.y = -this.width
}
this.sy = isQuick ? Math.random() * this.quickMaxSpeed + this.quickMinSpeed : Math.random() * this.maxSpeed + this.minSpeed
this.sx = this.dir === 'r' ? this.sy : -this.sy
this.z = isQuick ? Math.random() * 300 + 200 : 0
this.swingStep = 0.01 * Math.random()
this.swingRadian = Math.random() * (1.1 - 0.9) + 0.9
}
// 设置样式
setStyle () {
this.el.style.cssText = `
position: fixed;
left: 0;
top: 0;
display: block;
width: ${this.isRain ? 1 : this.width}px;
height: ${this.width}px;
opacity: ${this.opacity};
background-image: radial-gradient(#fff 0%, rgba(255, 255, 255, 0) 60%);
border-radius: 50%;
z-index: 9999999999999;
pointer-events: none;
transform: translate(${this.x}px, ${this.y}px) ${this.getRotate(this.sy, this.sx)};
`
}
// 渲染
render () {
this.el = document.createElement('div')
this.setStyle()
document.body.appendChild(this.el)
}
move () {
if (this.isSwing) {
// if (this.sx >= 1 || this.sx <= -1) {
// this.stepSx = -this.stepSx
// }
// this.sx += this.stepSx
if (this.swingRadian > 1.1 || this.swingRadian < 0.9) {
this.swingStep = -this.swingStep
}
this.swingRadian += this.swingStep
if (this.isRain) {
this.x += this.sx
} else {
this.x += this.sx * Math.sin(this.swingRadian * Math.PI)
}
this.y -= this.sy * Math.cos(this.swingRadian * Math.PI)
} else {
this.x += this.sx
this.y += this.sy
}
// 完全离开窗口就调一下初始化方法，另外还需要修改一下init方法，因为重新出现我们是希望它的y坐标为0或者小于0，这样就不会又凭空出现的感觉，而是从天上下来的
if (this.x < -this.width || this.x > this.windowWidth || this.y > this.windowHeight) {
this.init(true)
this.setStyle()
}
this.el.style.transform = `translate3d(${this.x}px, ${this.y}px, ${this.z}px) ${this.getRotate(this.sy, this.sx)}`
}
getRotate(sy, sx) {
return this.isRain ? `rotate(${sx === 0 ? 0 : (90 + Math.atan(sy / sx) * (180 / Math.PI))}deg)` : ''
}
}
class Snows {
constructor(opt = {}) {
this.num = opt.num || 100
this.opt = opt
this.snowList = []
this.createSnows()
this.moveSnow()
}
createSnows () {
this.snowList = []
for (let i = 0; i < this.num; i++) {
let snow = new Snow(this.opt)
snow.render()
this.snowList.push(snow)
}
}
moveSnow () {
window.requestAnimationFrame(() => {
this.snowList.forEach((item) => {
item.move()
})
this.moveSnow()
})
}
}
new Snows({
isRain: true,
num: 300,
maxSpeed: 15
})
new Snows({
isRain: false,
num: 150
})
</script>
随鼠标移动而变换的线条特效：
function() {
function n(n, e, t) {
return n.getAttribute(e) || t
}
function e(n) {
return document.getElementsByTagName(n)
}
function t() {
var t = e("script"),
o = t.length,
i = t[o - 1];
return {
l: o,
z: n(i, "zIndex", -1),
o: n(i, "opacity", .5),
c: n(i, "color", "0,0,0"),
n: n(i, "count", 99)
}
}
function o() {
a = m.width = window.innerWidth || document.documentElement.clientWidth || document.body.clientWidth,
c = m.height = window.innerHeight || document.documentElement.clientHeight || document.body.clientHeight
}
function i() {
r.clearRect(0, 0, a, c);
var n, e, t, o, m, l;
s.forEach(function(i, x) {
for (i.x += i.xa, i.y += i.ya, i.xa *= i.x > a || i.x < 0 ? -1 : 1, i.ya *= i.y > c || i.y < 0 ? -1 : 1, r.fillRect(i.x - .5, i.y - .5, 1, 1), e = x + 1; e < u.length; e++) n = u[e],
null !== n.x && null !== n.y && (o = i.x - n.x, m = i.y - n.y, l = o * o + m * m, l < n.max && (n === y && l >= n.max / 2 && (i.x -= .03 * o, i.y -= .03 * m), t = (n.max - l) / n.max, r.beginPath(), r.lineWidth = t / 2, r.strokeStyle = "rgba(" + d.c + "," + (t + .2) + ")", r.moveTo(i.x, i.y), r.lineTo(n.x, n.y), r.stroke()))
}),
x(i)
}
var a, c, u, m = document.createElement("canvas"),
d = t(),
l = "c_n" + d.l,
r = m.getContext("2d"),
x = window.requestAnimationFrame || window.webkitRequestAnimationFrame || window.mozRequestAnimationFrame || window.oRequestAnimationFrame || window.msRequestAnimationFrame ||
function(n) {
window.setTimeout(n, 1e3 / 45)
},
w = Math.random,
y = {
x: null,
y: null,
max: 2e4
};
m.id = l,
m.style.cssText = "position:fixed;top:0;left:0;z-index:" + d.z + ";opacity:" + d.o,
e("body")[0].appendChild(m),
o(),
window.onresize = o,
window.onmousemove = function(n) {
n = n || window.event,
y.x = n.clientX,
y.y = n.clientY
},
window.onmouseout = function() {
y.x = null,
y.y = null
};
for (var s = [], f = 0; d.n > f; f++) {
var h = w() * a,
g = w() * c,
v = 2 * w() - 1,
p = 2 * w() - 1;
s.push({
x: h,
y: g,
xa: v,
ya: p,
max: 6e3
})
}
u = s.concat([y]),
setTimeout(function() {
i()
},
100)
} ();
