<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en"> <head> <meta http-equiv="Content-Type" content="text/html;charset=UTF-8"> <style> *{margin:0;padding:0;} body{background:#000;overflow:hidden;} input{ width: 150px; height: 30px; margin-left:-75px; position:absolute; bottom:30px; left:50%; background: #fcfff4; background: linear-gradient(to bottom, #fcfff4 0%, #dfe5d7 40%, #b3bead 100%); box-shadow: 0px 2px 5px 0px rgba(0, 0, 0, 0.3); border:none; border-radius:10px; text-indent:30px; } input,button:focus{ outline:none; } button{ width: 30px; height: 30px; margin-left:45px; border:none; border-radius:10px; background: #fcfff4; background: linear-gradient(to bottom, #fcfff4 0%, #dfe5d7 40%, #b3bead 100%); box-shadow: 0px 2px 5px 0px rgba(0, 0, 0, 0.3); position:absolute; bottom:30px; left:50%; } </style> </head> <script type="text/javascript"> window.onload = function(){ canvas = document.getElementById("mycanvas"); ctx = canvas.getContext("2d"); focallength = 250; var txt = document.getElementById("txt"); var btn = document.getElementById("btn"); var particleArr = getImgData(txt.value); var pause = false; var timer; //初始化位置 initMove(); function initMove(){ particleArr.forEach(function(){ this.locx =parseInt(Math.random()*canvas.width); this.locy =parseInt(Math.random()*canvas.height); this.locz =Math.random()*focallength*2 - focallength; this.x =parseInt(Math.random()*canvas.width); this.y =parseInt(Math.random()*canvas.height); this.z = Math.random()*focallength*2 - focallength; this.paint(); }); startMove(); } //速度 var lastTime; var derection = true; function startMove(){ clearInterval(timer); var thisTime = new Date(); ctx.clearRect(0,0,canvas.width , canvas.height); particleArr.forEach(function(){ var particle = this; if(derection){ if (Math.abs(particle.disx - particle.x) < 0.1 && Math.abs(particle.disy - particle.y) < 0.1 && Math.abs(particle.disz - particle.z)<0.1) { particle.x = particle.disx; particle.y = particle.disy; particle.z = particle.disz; if(thisTime - lastTime > 300){ derection = false; } }else{ particle.x = particle.x + (particle.disx - particle.x) * 0.1; particle.y = particle.y + (particle.disy - particle.y) * 0.1; particle.z = particle.z + (particle.disz - particle.z) * 0.1; lastTime = new Date() } }else{ if (Math.abs(particle.locx - particle.x) < 0.1 && Math.abs(particle.locy - particle.y) < 0.1 && Math.abs(particle.locz - particle.z)<0.1) { particle.x = particle.locx; particle.y = particle.locy; particle.z = particle.locz; pause = true; clearInterval(timer); move(); }else{ particle.x = particle.x + (particle.locx - particle.x) * 0.1; particle.y = particle.y + (particle.locy - particle.y) * 0.1; particle.z = particle.z + (particle.locz - particle.z) * 0.1; pause = false; } } particle.paint(); }); if(!pause) { if("requestAnimationFrame" in window){ requestAnimationFrame(startMove); } else if("webkitRequestAnimationFrame" in window){ webkitRequestAnimationFrame(startMove); } else if("msRequestAnimationFrame" in window){ msRequestAnimationFrame(startMove); } else if("mozRequestAnimationFrame" in window){ mozRequestAnimationFrame(startMove); } } } //点击改变文字 btn.onclick = function(){ if(!pause){ return } clearInterval(timer); particleArr = getImgData(txt.value); derection=true; pause = false; initMove(); } //键盘回车按键 document.onkeydown=function(e) { var e = e || event if(!pause){ return } if(e.keyCode=="13"){ clearInterval(timer) particleArr = getImgData(txt.value); derection=true; pause = false; initMove(); } } function move(){ timer = setInterval(makeParticle,10) } function makeParticle(){ ctx.clearRect(0,0,1432,768); for(var i = 0 ; i < particleArr.length; i++){ var particle = particleArr[i]; particle.paint(); } } } Array.prototype.forEach = function(callback){ for(var i=0;i<this.length;i++){ callback.call(this[i]); } } //根据getImageData接口重绘文字 function getImgData(text){ drawText(text); var imgData = ctx.getImageData(0,0,canvas.width,canvas.height); ctx.clearRect(0,0,canvas.width,canvas.height); var newArr = []; for(var i = 0 ; i < imgData.width ; i +=6){ for(var j = 0 ; j < imgData.height ; j+=6){ var num = (j*imgData.width+i)*4; if(imgData.data[num]>=128){ var particle = new Particle(i-3,j-3,0,3); newArr.push(particle); } } } return newArr } //画字 function drawText(text){ ctx.clearRect(0,0,canvas.width,canvas.height); ctx.save(); ctx.font = "200px 微软雅黑 bold"; ctx.fillStyle ="rgba(255,255,255,1)";//纯色 方便扫面 ctx.textAlign = "center"; ctx.textBaseline = "middle"; ctx.fillText(text , canvas.width/2 , canvas.height/2); ctx.restore(); } //定义粒子 构造函数 var Particle = function(x,y,z,r){ this.disx = x;//文字锁定的位置 this.disy = y; this.disz = z; this.x = x; this.y = y; this.z = z; this.locx = 0; this.locy = 0;// 运动前位置 this.locz = 0; this.radius = r; this.col = "rgba("+parseInt(Math.random()*255)+","+parseInt(Math.random()*255)+","+parseInt(Math.random()*255)+",1)"; } Particle.prototype={ paint:function(){ ctx.save(); ctx.beginPath(); var scale = focallength/(focallength + this.z); ctx.arc(canvas.width/2 + (this.x-canvas.width/2)*scale , canvas.height/2 + (this.y-canvas.height/2) * scale, this.radius*scale , 0 , 2*Math.PI); ctx.fillStyle = "rgba("+parseInt(Math.random()*255)+","+parseInt(Math.random()*255)+","+parseInt(Math.random()*255)+","+ scale +")"; ctx.fill() ctx.restore(); } } </script> <body> <canvas id = "mycanvas" width="1423" height = "768" ></canvas> <input type="text" value="Canvas" id="txt"> <button id = "btn">获取</button> </body> </html>
时间: 2024-10-13 01:11:50