网站添加Sketch.JS鼠标点击特效Canvas点击效果

点几下网页就卡成渣了，后来找到了一个基于sketch.js效果，sketch 效率也高很多，完全不会卡，修改了一下替换了之前的。

实测缺点：动画未结束时切换窗口，动画会停留直到切换回来才会继续。

JS代码

代码中包含了sketch.min.js的源码，如果你的网站已经引用了，请删掉下面的1到2行。

/* Copyright (C) 2013 Justin Windle sketch.min.js, http://soulwire.co.uk */
var Sketch=function(){"use strict";function e(e){return"[object Array]"==Object.prototype.toString.call(e)}function t(e){return"function"==typeof e}function n(e){return"number"==typeof e}function o(e){return"string"==typeof e}function r(e){return E[e]||String.fromCharCode(e)}function i(e,t,n){for(var o in t)(n||!e.hasOwnProperty(o))&&(e[o]=t[o]);return e}function u(e,t){return function(){e.apply(t,arguments)}}function a(e){var n={};for(var o in e)n[o]=t(e[o])?u(e[o],e):e[o];return n}function c(e){function n(n){t(n)&&n.apply(e,[].splice.call(arguments,1))}function u(e){for(_=0;_<J.length;_++)G=J[_],o(G)?O[(e?"add":"remove")+"EventListener"].call(O,G,k,!1):t(G)?k=G:O=G}function c(){L(T),T=I(c),U||(n(e.setup),U=t(e.setup),n(e.resize)),e.running&&!j&&(e.dt=(B=+new Date)-e.now,e.millis+=e.dt,e.now=B,n(e.update),e.autoclear&&K&&e.clear(),n(e.draw)),j=++j%e.interval}function l(){O=Y?e.style:e.canvas,D=Y?"px":"",e.fullscreen&&(e.height=w.innerHeight,e.width=w.innerWidth),O.height=e.height+D,O.width=e.width+D,e.retina&&K&&X&&(O.height=e.height*X,O.width=e.width*X,O.style.height=e.height+"px",O.style.width=e.width+"px",e.scale(X,X)),U&&n(e.resize)}function s(e,t){return N=t.getBoundingClientRect(),e.x=e.pageX-N.left-w.scrollX,e.y=e.pageY-N.top-w.scrollY,e}function f(t,n){return s(t,e.element),n=n||{},n.ox=n.x||t.x,n.oy=n.y||t.y,n.x=t.x,n.y=t.y,n.dx=n.x-n.ox,n.dy=n.y-n.oy,n}function g(e){if(e.preventDefault(),W=a(e),W.originalEvent=e,W.touches)for(M.length=W.touches.length,_=0;_<W.touches.length;_++)M[_]=f(W.touches[_],M[_]);else M.length=0,M[0]=f(W,V);return i(V,M[0],!0),W}function h(t){for(t=g(t),q=(Q=J.indexOf(z=t.type))-1,e.dragging=/down|start/.test(z)?!0:/up|end/.test(z)?!1:e.dragging;q;)o(J[q])?n(e[J[q--]],t):o(J[Q])?n(e[J[Q++]],t):q=0}function p(t){F=t.keyCode,H="keyup"==t.type,Z[F]=Z[r(F)]=!H,n(e[t.type],t)}function v(t){e.autopause&&("blur"==t.type?b:C)(),n(e[t.type],t)}function C(){e.now=+new Date,e.running=!0}function b(){e.running=!1}function P(){(e.running?b:C)()}function A(){K&&e.clearRect(0,0,e.width,e.height)}function S(){R=e.element.parentNode,_=x.indexOf(e),R&&R.removeChild(e.element),~_&&x.splice(_,1),u(!1),b()}var T,k,O,R,N,_,D,B,G,W,z,F,H,q,Q,j=0,M=[],U=!1,X=w.devicePixelRatio,Y=e.type==m,K=e.type==d,V={x:0,y:0,ox:0,oy:0,dx:0,dy:0},J=[e.element,h,"mousedown","touchstart",h,"mousemove","touchmove",h,"mouseup","touchend",h,"click",y,p,"keydown","keyup",w,v,"focus","blur",l,"resize"],Z={};for(F in E)Z[E[F]]=!1;return i(e,{touches:M,mouse:V,keys:Z,dragging:!1,running:!1,millis:0,now:0/0,dt:0/0,destroy:S,toggle:P,clear:A,start:C,stop:b}),x.push(e),e.autostart&&C(),u(!0),l(),c(),e}for(var l,s,f="E LN10 LN2 LOG2E LOG10E PI SQRT1_2 SQRT2 abs acos asin atan ceil cos exp floor log round sin sqrt tan atan2 pow max min".split(" "),g="__hasSketch",h=Math,d="canvas",p="webgl",m="dom",y=document,w=window,x=[],v={fullscreen:!0,autostart:!0,autoclear:!0,autopause:!0,container:y.body,interval:1,globals:!0,retina:!1,type:d},E={8:"BACKSPACE",9:"TAB",13:"ENTER",16:"SHIFT",27:"ESCAPE",32:"SPACE",37:"LEFT",38:"UP",39:"RIGHT",40:"DOWN"},C={CANVAS:d,WEB_GL:p,WEBGL:p,DOM:m,instances:x,install:function(t){if(!t[g]){for(var o=0;o<f.length;o++)t[f[o]]=h[f[o]];i(t,{TWO_PI:2*h.PI,HALF_PI:h.PI/2,QUATER_PI:h.PI/4,random:function(t,o){return e(t)?t[~~(h.random()*t.length)]:(n(o)||(o=t||1,t=0),t+h.random()*(o-t))},lerp:function(e,t,n){return e+n*(t-e)},map:function(e,t,n,o,r){return(e-t)/(n-t)*(r-o)+o}}),t[g]=!0}},create:function(e){return e=i(e||{},v),e.globals&&C.install(self),l=e.element=e.element||y.createElement(e.type===m?"div":"canvas"),s=e.context=e.context||function(){switch(e.type){case d:return l.getContext("2d",e);case p:return l.getContext("webgl",e)||l.getContext("experimental-webgl",e);case m:return l.canvas=l}}(),e.container.appendChild(l),C.augment(s,e)},augment:function(e,t){return t=i(t||{},v),t.element=e.canvas||e,t.element.className+=" sketch",i(e,t,!0),c(e)}},b=["ms","moz","webkit","o"],P=self,A=0,S="AnimationFrame",T="request"+S,k="cancel"+S,I=P[T],L=P[k],O=0;O<b.length&&!I;O++)I=P[b[O]+"Request"+S],L=P[b[O]+"Cancel"+T];return P[T]=I=I||function(e){var t=+new Date,n=h.max(0,16-(t-A)),o=setTimeout(function(){e(t+n)},n);return A=t+n,o},P[k]=L=L||function(e){clearTimeout(e)},C}();

//往上是sketch.min.js的代码
if(document.getElementById("clickCanvas")) {
    function Particle(x, y, radius) {
        this.init(x, y, radius);
    }
    Particle.prototype = {
        init : function(x, y, radius) {
            this.alive = true;
            this.radius = radius || 10;
            this.wander = 0.15;
            this.theta = random(TWO_PI);
            this.drag = 0.92;
            this.color = '#ffeb3b';

            this.x = x || 0.0;
            this.y = y || 0.0;
            this.vx = 0.0;
            this.vy = 0.0;
        },
        move : function() {
            this.x += this.vx;
            this.y += this.vy;
            this.vx *= this.drag;
            this.vy *= this.drag;
            this.theta += random(-0.5, 0.5) * this.wander;
            this.vx += sin(this.theta) * 0.1;
            this.vy += cos(this.theta) * 0.1;
            this.radius *= 0.96;
            this.alive = this.radius > 0.5;
        },
        draw : function(ctx) {
            ctx.beginPath();
            ctx.arc(this.x, this.y, this.radius, 0, TWO_PI);
            ctx.fillStyle = this.color;
            ctx.fill();
        }
    };
    var MAX_PARTICLES = 50;
    //圆点颜色库
    var COLOURS = [ "#5ee4ff", "#f44033", "#ffeb3b", "#F38630", "#FA6900", "#f403e8", "#F9D423" ];
    var particles = [];
    var pool = [];
    var clickparticle = Sketch.create({
        container : document.getElementById('clickCanvas')
    });
    clickparticle.spawn = function(x, y) {
        if (particles.length >= MAX_PARTICLES)
            pool.push(particles.shift());
        particle = pool.length ? pool.pop() : new Particle();
        particle.init(x, y, random(5, 20));//圆点大小范围
        particle.wander = random(0.5, 2.0);
        particle.color = random(COLOURS);
        particle.drag = random(0.9, 0.99);
        theta = random(TWO_PI);
        force = random(1, 5);
        particle.vx = sin(theta) * force;
        particle.vy = cos(theta) * force;
        particles.push(particle);
    };
    clickparticle.update = function() {
        var i, particle;
        for (i = particles.length - 1; i >= 0; i--) {
            particle = particles[i];
            if (particle.alive)
                particle.move();
            else
                pool.push(particles.splice(i, 1)[0]);
        }
    };
    clickparticle.draw = function() {
        clickparticle.globalCompositeOperation = 'lighter';
        for ( var i = particles.length - 1; i >= 0; i--) {
            particles[i].draw(clickparticle);
        }
    };
    //按下时显示效果，mousedown 换成 click 为点击时显示效果（我用的 click）
    document.addEventListener("mousedown", function(e) {
      var max, j;
      //排除一些元素
      "TEXTAREA" !== e.target.nodeName && "INPUT" !== e.target.nodeName && "A" !== e.target.nodeName && "I" !== e.target.nodeName && "IMG" !== e.target.nodeName 
      && function() {
          for (max = random(15, 20), j = 0; j < max; j++) 
          clickparticle.spawn(e.clientX, e.clientY);
      }();
    });
}

部署方法

复制上面的 js 代码到主题的主 js 文件最下面，或者保存为一个单独的 js 文件，然后引入主题。如果你是单独保存为一个 js 文件，请在 footer 引入js文件。

然后在页面 body 标签中加入

<div id="clickCanvas" style=" position:fixed;left:0;top:0;z-index:999999999;pointer-events:none;"></div>

WordPress 可以在主题的 header.php 文件在<body>下方（如果 header.php 中没有，请全盘搜素下 <body ），加入以下代码。

<?php if(!wp_is_mobile()): ?>
<div id="clickCanvas" style=" position:fixed;left:0;top:0;z-index:999999999;pointer-events:none;"></div>
<?php endif; ?>

如果移动端也想要这效果，请删除上面代码的第1行和第3行。

PS：如果你不喜欢，可以自定义一些设置，比如大小、颜色、速度等，看参数名称调整就可以了