HTML5 verwendet Canvas zum Zeichnen von Sonnensystemeffekten

In diesem Artikel wird hauptsächlich der Effekt der Verwendung von Canvas zum Zeichnen des Sonnensystems in HTML5 vorgestellt. Freunde, die es benötigen, können darauf verweisen:

<canvas id="canvas" width="1000"    style="max-width:90%" style="background-color: #000;"></canvas>

Der Code ist wie folgt:

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);

Das Obige ist der gesamte Inhalt dieses Kapitels. Weitere verwandte Tutorials finden Sie unter Html5-Video-Tutorial!