<!DOCTYPE html>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge, chrome=1">
<meta name="viewport" content="width=device-width, initial-scale=1.0, minimum-scale=1.0, maximum-scale=1.0, user-scalable=no">
<meta name="robots" content="noindex">
<title>io-fx16</title>
<meta name="author" content="iowen.cn">
<style>
#bg {
position:fixed;
top:0;
left:0;
width:100%;
height:100%;
z-index:-1;
background-color: #0b5a99;
background-image: linear-gradient(335deg, #0b5a99 0%, #49bee8 100%);
}
#bg canvas {
position:absolute;
top:0;
left:0;
width:100%;
height:100%;
}
</style>
</head>
<body>
<div id="bg">
<canvas></canvas>
<canvas></canvas>
<canvas></canvas>
</div>
<script src="https://cdn.staticfile.org/jquery/2.2.4/jquery.min.js"></script>
<script>
(function($){
var canvas = $('#bg').children('canvas'),
background = canvas[0],
foreground1 = canvas[1],
foreground2 = canvas[2],
config = {
circle: {
amount: 18,
layer: 3,
color: [157, 97, 207],
alpha: 0.3
},
line: {
amount: 12,
layer: 3,
color: [255, 255, 255],
alpha: 0.3
},
speed: 0.5,
angle: 20
};
if (background.getContext){
var bctx = background.getContext('2d'),
fctx1 = foreground1.getContext('2d'),
fctx2 = foreground2.getContext('2d'),
M = window.Math, // Cached Math
degree = config.angle/360*M.PI*2,
circles = [],
lines = [],
wWidth, wHeight, timer;
requestAnimationFrame = window.requestAnimationFrame ||
window.mozRequestAnimationFrame ||
window.webkitRequestAnimationFrame ||
window.msRequestAnimationFrame ||
window.oRequestAnimationFrame ||
function(callback, element) { setTimeout(callback, 1000 / 60); };
cancelAnimationFrame = window.cancelAnimationFrame ||
window.mozCancelAnimationFrame ||
window.webkitCancelAnimationFrame ||
window.msCancelAnimationFrame ||
window.oCancelAnimationFrame ||
clearTimeout;
var setCanvasHeight = function(){
wWidth = $(window).width();
wHeight = $(window).height(),
canvas.each(function(){
this.width = wWidth;
this.height = wHeight;
});
};
var drawCircle = function(x, y, radius, color, alpha){
var gradient = fctx1.createRadialGradient(x, y, radius, x, y, 0);
gradient.addColorStop(0, 'rgba('+color[0]+','+color[1]+','+color[2]+','+alpha+')');
gradient.addColorStop(1, 'rgba('+color[0]+','+color[1]+','+color[2]+','+(alpha-0.1)+')');
fctx1.beginPath();
fctx1.arc(x, y, radius, 0, M.PI*2, true);
fctx1.fillStyle = gradient;
fctx1.fill();
};
var drawLine = function(x, y, width, color, alpha){
var endX = x+M.sin(degree)*width,
endY = y-M.cos(degree)*width,
gradient = fctx2.createLinearGradient(x, y, endX, endY);
gradient.addColorStop(0, 'rgba('+color[0]+','+color[1]+','+color[2]+','+alpha+')');
gradient.addColorStop(1, 'rgba('+color[0]+','+color[1]+','+color[2]+','+(alpha-0.1)+')');
fctx2.beginPath();
fctx2.moveTo(x, y);
fctx2.lineTo(endX, endY);
fctx2.lineWidth = 3;
fctx2.lineCap = 'round';
fctx2.strokeStyle = gradient;
fctx2.stroke();
};
var drawBack = function(){
bctx.clearRect(0, 0, wWidth, wHeight);
var gradient = [];
gradient[0] = bctx.createRadialGradient(wWidth*0.3, wHeight*0.1, 0, wWidth*0.3, wHeight*0.1, wWidth*0.9);
gradient[0].addColorStop(0, 'rgb(0, 26, 77)');
gradient[0].addColorStop(1, 'transparent');
bctx.translate(wWidth, 0);
bctx.scale(-1,1);
bctx.beginPath();
bctx.fillStyle = gradient[0];
bctx.fillRect(0, 0, wWidth, wHeight);
gradient[1] = bctx.createRadialGradient(wWidth*0.1, wHeight*0.1, 0, wWidth*0.3, wHeight*0.1, wWidth);
gradient[1].addColorStop(0, 'rgb(0, 150, 240)');
gradient[1].addColorStop(0.8, 'transparent');
bctx.translate(wWidth, 0);
bctx.scale(-1,1);
bctx.beginPath();
bctx.fillStyle = gradient[1];
bctx.fillRect(0, 0, wWidth, wHeight);
gradient[2] = bctx.createRadialGradient(wWidth*0.1, wHeight*0.5, 0, wWidth*0.1, wHeight*0.5, wWidth*0.5);
gradient[2].addColorStop(0, 'rgb(40, 20, 105)');
gradient[2].addColorStop(1, 'transparent');
bctx.beginPath();
bctx.fillStyle = gradient[2];
bctx.fillRect(0, 0, wWidth, wHeight);
};
var animate = function(){
var sin = M.sin(degree),
cos = M.cos(degree);
if (config.circle.amount > 0 && config.circle.layer > 0){
fctx1.clearRect(0, 0, wWidth, wHeight);
for (var i=0, len = circles.length; i<len; i++){
var item = circles[i],
x = item.x,
y = item.y,
radius = item.radius,
speed = item.speed;
if (x > wWidth + radius){
x = -radius;
} else if (x < -radius){
x = wWidth + radius
} else {
x += sin*speed;
}
if (y > wHeight + radius){
y = -radius;
} else if (y < -radius){
y = wHeight + radius;
} else {
y -= cos*speed;
}
item.x = x;
item.y = y;
drawCircle(x, y, radius, item.color, item.alpha);
}
}
if (config.line.amount > 0 && config.line.layer > 0){
fctx2.clearRect(0, 0, wWidth, wHeight);
for (var j=0, len = lines.length; j<len; j++){
var item = lines[j],
x = item.x,
y = item.y,
width = item.width,
speed = item.speed;
if (x > wWidth + width * sin){
x = -width * sin;
} else if (x < -width * sin){
x = wWidth + width * sin;
} else {
x += sin*speed;
}
if (y > wHeight + width * cos){
y = -width * cos;
} else if (y < -width * cos){
y = wHeight + width * cos;
} else {
y -= cos*speed;
}
item.x = x;
item.y = y;
drawLine(x, y, width, item.color, item.alpha);
}
}
timer = requestAnimationFrame(animate);
};
var createItem = function(){
circles = [];
lines = [];
if (config.circle.amount > 0 && config.circle.layer > 0){
for (var i=0; i<config.circle.amount/config.circle.layer; i++){
for (var j=0; j<config.circle.layer; j++){
circles.push({
x: M.random() * wWidth,
y: M.random() * wHeight,
radius: M.random()*(20+j*5)+(20+j*5),
color: config.circle.color,
alpha: M.random()*0.2+(config.circle.alpha-j*0.1),
speed: config.speed*(1+j*0.5)
});
}
}
}
if (config.line.amount > 0 && config.line.layer > 0){
for (var m=0; m<config.line.amount/config.line.layer; m++){
for (var n=0; n<config.line.layer; n++){
lines.push({
x: M.random() * wWidth,
y: M.random() * wHeight,
width: M.random()*(20+n*5)+(20+n*5),
color: config.line.color,
alpha: M.random()*0.2+(config.line.alpha-n*0.1),
speed: config.speed*(1+n*0.5)
});
}
}
}
cancelAnimationFrame(timer);
timer = requestAnimationFrame(animate);
drawBack();
};
$(document).ready(function(){
setCanvasHeight();
createItem();
});
$(window).resize(function(){
setCanvasHeight();
createItem();
});
}
})(jQuery);
</script>
</body>
</html>
