博客园页脚html代码,博客园页脚动态背景代码
作者：互联网
Title
!function() {//封装方法，压缩之后减少文件大小
functionget_attribute(node, attr, default_value) {returnnode.getAttribute(attr)||default_value;
}//封装方法，压缩之后减少文件大小
functionget_by_tagname(name) {returndocument.getElementsByTagName(name);
}//获取配置参数
functionget_config_option() {varscripts=get_by_tagname("script"),
script_len=scripts.length,
script=scripts[script_len- 1];//当前加载的script
return{
l: script_len,//长度，用于生成id用
z: get_attribute(script,"zIndex",-1),//z-index
o: get_attribute(script,"opacity",0.8),//opacity
c: get_attribute(script,"color","255,255,255"),//color
n: get_attribute(script,"count",350)//count
};
}//设置canvas的高宽
functionset_canvas_size() {
canvas_width=the_canvas.width=window.innerWidth||document.documentElement.clientWidth||document.body.clientWidth,
canvas_height=the_canvas.height=window.innerHeight||document.documentElement.clientHeight||document.body.clientHeight;
}//绘制过程
functiondraw_canvas() {
context.clearRect(0,0, canvas_width, canvas_height);//随机的线条和当前位置联合数组
vare, i, d, x_dist, y_dist, dist;//临时节点
//遍历处理每一个点
random_points.forEach(function(r, idx) {
r.x+=r.xa,
r.y+=r.ya,//移动
r.xa*=r.x>canvas_width||r.x< 0 ? -1:1,
r.ya*=r.y>canvas_height||r.y< 0 ? -1:1,//碰到边界，反向反弹
context.fillRect(r.x- 0.5, r.y- 0.5,1,1);//绘制一个宽高为1的点
//从下一个点开始
for(i=idx+ 1; i
e=all_array[i];//当前点存在
if(null !==e.x&& null !==e.y) {
x_dist=r.x-e.x;//x轴距离 l
y_dist=r.y-e.y;//y轴距离 n
dist=x_dist*x_dist+y_dist*y_dist;//总距离, m
dist=e.max/ 2 &&(r.x-= 0.03 *x_dist, r.y-= 0.03 *y_dist),//靠近的时候加速
d=(e.max-dist)/e.max,
context.beginPath(),
context.lineWidth=d/ 2,
context.strokeStyle= "#555555",//这里是线条的颜色
context.moveTo(r.x, r.y),
context.lineTo(e.x, e.y),
context.stroke());
}
}
}), frame_func(draw_canvas);
}//创建画布，并添加到body中
varthe_canvas=document.createElement("canvas"),//画布
config=get_config_option(),//配置
canvas_id= "c_n" +config.l,//canvas id
context=the_canvas.getContext("2d"), canvas_width, canvas_height,
frame_func=window.requestAnimationFrame||window.webkitRequestAnimationFrame||window.mozRequestAnimationFrame||window.oRequestAnimationFrame||window.msRequestAnimationFrame|| function(func) {
window.setTimeout(func,1000 / 40);
}, random=Math.random,
current_point={
x:null,//当前鼠标x
y:null,//当前鼠标y
max:20000 //圈半径的平方
},
all_array;
the_canvas.id=canvas_id;
the_canvas.style.cssText= "position:fixed;top:0;left:0;z-index:" +config.z+ ";opacity:" +config.o;
get_by_tagname("body")[0].appendChild(the_canvas);//初始化画布大小
set_canvas_size();
window.οnresize=set_canvas_size;//当时鼠标位置存储，离开的时候，释放当前位置信息
window.οnmοusemοve= function(e) {
e=e||window.event;
current_point.x=e.clientX;
current_point.y=e.clientY;
}, window.οnmοuseοut= function() {
current_point.x= null;
current_point.y= null;
};//随机生成config.n条线位置信息
for(varrandom_points=[], i= 0; config.n>i; i++) {varx=random()*canvas_width,//随机位置
y=random()*canvas_height,
xa= 2 *random()- 1,//随机运动方向
ya= 2 *random()- 1;//随机点
random_points.push({
x: x,
y: y,
xa: xa,
ya: ya,
max:6000 //沾附距离
});
}
all_array=random_points.concat([current_point]);//0.1秒后绘制
setTimeout(function() {
draw_canvas();
},100);
}();
标签：canvas,random,dist,页脚,博客园,script,window,context,代码 来源： https://www.cnblogs.com/aixuexi666888/p/15509836.html