代码如下：
<!DOCTYPE html><html lang="en"><head><meta charset="UTF-8"><title>Title</title></head><body><canvas id="cas" width="840" height="945"></canvas><script>var canvas = document.getElementById("cas");var ctx = canvas.getContext("2d");resize();window.onresize = resize;function resize() {canvas.width = window.innerWidth || document.documentElement.clientWidth || document.body.clientWidth;canvas.height = window.innerHeight || document.documentElement.clientHeight || document.body.clientHeight;}var RAF = (function() {return window.requestAnimationFrame || window.webkitRequestAnimationFrame || window.mozRequestAnimationFrame || window.oRequestAnimationFrame || window.msRequestAnimationFrame || function(callback) {window.setTimeout(callback, 1000 / 60);};})();// 鼠标活动时，获取鼠标坐标var warea = {x: null, y: null, max: 20000};window.onmousemove = function(e) {e = e || window.event;warea.x = e.clientX;warea.y = e.clientY;};window.onmouseout = function(e) {warea.x = null;warea.y = null;};// 添加粒子// x，y为粒子坐标，xa, ya为粒子xy轴加速度，max为连线的最大距离var dots = [];for (var i = 0; i < 300; i++) {var x = Math.random() * canvas.width;var y = Math.random() * canvas.height;var xa = Math.random() * 2 - 1;var ya = Math.random() * 2 - 1;dots.push({x: x,y: y,xa: xa,ya: ya,max: 6000})}// 延迟100秒开始执行动画，如果立即执行有时位置计算会出错setTimeout(function() {animate();}, 100);// 每一帧循环的逻辑function animate() {ctx.clearRect(0, 0, canvas.width, canvas.height);// 将鼠标坐标添加进去，产生一个用于比对距离的点数组var ndots = [warea].concat(dots);dots.forEach(function(dot) {// 粒子位移dot.x += dot.xa;dot.y += dot.ya;// 遇到边界将加速度反向dot.xa *= (dot.x > canvas.width || dot.x < 0) ? -1 : 1;dot.ya *= (dot.y > canvas.height || dot.y < 0) ? -1 : 1;// 绘制点ctx.fillRect(dot.x - 0.5, dot.y - 0.5, 1, 1);// 循环比对粒子间的距离for (var i = 0; i < ndots.length; i++) {var d2 = ndots[i];if (dot === d2 || d2.x === null || d2.y === null) continue;var xc = dot.x - d2.x;var yc = dot.y - d2.y;// 两个粒子之间的距离var dis = xc * xc + yc * yc;// 距离比var ratio;// 如果两个粒子之间的距离小于粒子对象的max值，则在两个粒子间画线if (dis < d2.max) {// 如果是鼠标，则让粒子向鼠标的位置移动if (d2 === warea && dis > (d2.max / 2)) {dot.x -= xc * 0.03;dot.y -= yc * 0.03;}// 计算距离比ratio = (d2.max - dis) / d2.max;// 画线ctx.beginPath();ctx.lineWidth = ratio / 2;//线条颜色ctx.strokeStyle = 'rgba(0,0,0,' + (ratio + 0.2) + ')';ctx.moveTo(dot.x, dot.y);ctx.lineTo(d2.x, d2.y);ctx.stroke();}}// 将已经计算过的粒子从数组中删除ndots.splice(ndots.indexOf(dot), 1);});RAF(animate);}</script></body></html>
效果如下：
