Cet article présente principalement l'effet de l'utilisation de canevas pour dessiner le système solaire en HTML5. Les amis qui en ont besoin peuvent s'y référer :
<canvas id="canvas" width="1000" style="max-width:90%" style="background-color: #000;"></canvas>
Le code est. comme suit :
var canvas=document.getElementById("canvas"); var cxt=canvas.getContext("2d"); function DrawTrack(){ for(var i=0;i<8;i++){ cxt.beginPath(); cxt.arc(500,500,(i+1)*50,0,360,false); cxt.closePath(); cxt.strokeStyle="#fff"; cxt.stroke(); } } function DrawStart(x,y,radius,cycle,sColor,eColor){ //画出星球需要哪些属性 //星球的坐标点 this.x=x; this.y=y; //星球的半径 this.radius=radius; //星球的颜色(开始色,结束色) this.sColor=sColor; this.eColor=eColor; //创建一个渐变色空对象 this.color=null; this.time=0; //公共周期 this.cycle=cycle; this.draw=function(){ cxt.save(); cxt.translate(500,500); //设置旋转角度 cxt.rotate(this.time*360/this.cycle*Math.PI/180); cxt.beginPath(); cxt.arc(this.x,this.y,this.radius,0,360,false); cxt.closePath(); this.color=cxt.createRadialGradient(this.x,this.y,0,this.x,this.y,this.radius); this.color.addColorStop(0,this.sColor); this.color.addColorStop(1,this.eColor); cxt.fillStyle=this.color; cxt.fill(); cxt.restore(); this.time+=1; } }</p> <p> function Sun(){//太阳1 DrawStart.call(this,0,0,20,0,"#f00","#f90"); } function Mercury(){//水星2 DrawStart.call(this,0,-50,10,87.70,"#A69697","#5c3e40"); } function Venus(){//金星3 DrawStart.call(this,0,-100,10,224.71,"#c4bbac","#1f1315"); } function Earth(){//地球4 DrawStart.call(this,0,-150,10,365.224,"#78b1e8","#050c12"); } function Mars(){//火星5 DrawStart.call(this,0,-200,10,686.98,"#cec9b6","#76422d"); } function Jupiter(){//木星6 DrawStart.call(this,0,-250,10,4332.589,"#c0a48e","#322"); } function Saturn(){//土星7 DrawStart.call(this,0,-300,10,10759.5,"#f7f9e3","#5c4533"); } function Uranus(){//天王星8 DrawStart.call(this,0,-350,10,30799.95,"#a7e1e5","#19243a"); } function Neptune(){//天王星9 DrawStart.call(this,0,-400,10,60152.95,"#0661b2","#1E3b73"); } var s=new Sun();//1 var m=new Mercury();//2 var v=new Venus();//3 var e=new Earth();//4 var ma=new Mars();//5 var j=new Jupiter();//6 var sa=new Saturn();//7 var ur=new Uranus();//8 var ne=new Neptune();//9 setInterval(function(){ cxt.clearRect(0,0,1000,1000); DrawTrack(); s.draw(); m.draw(); v.draw(); e.draw(); ma.draw(); j.draw(); sa.draw(); ur.draw(); ne.draw(); },10);
Ce qui précède est l'intégralité du contenu de ce chapitre. Pour plus de didacticiels connexes, veuillez visiter le Tutoriel vidéo HTML5 !