标签：style io color os ar java for sp on
学习canvas吃球小效果
最后导出图片及图片编码
<!doctype html>
<html>
<head>
<meta charset="utf-8">
<title>无标题文档</title>
<style>
*{margin:0;padding:0}
</style>
</head>
<body>
<canvas id="myCanvas" width="800" height="500" style="border:1px solid #c3c3c3;"></canvas>
<script type="text/javascript">
var canvas=document.getElementById(‘myCanvas‘);
var c=document.getElementById("myCanvas");
var cxt=c.getContext("2d");
var start1=60,radius1=50,size=3,start2=250,radius2=20;
fn();
function fn()
{
cxt.clearRect(0,0,canvas.width,canvas.height);
cxt.fillStyle="#FF0000";
cxt.beginPath(); //起始一条路径，或重置当前路径
cxt.arc(start1,200,radius1,Math.PI*0.2,Math.PI*1.8,false);//创建弧/曲线（用于创建圆形或部分圆）
cxt.lineTo(start1,200);
cxt.closePath();//创建从当前点回到起始点的路径
cxt.fill();//填充当前绘图（路径）
for(var i=0;i<size;i++)
{
getCircle(start2+i*200,200,radius2,0,‘blue‘)
};
function getCircle(x,y,r,s,color){
cxt.fillStyle=color;
cxt.beginPath()
cxt.arc(x,y,r,s,Math.PI*2);
cxt.fill();
};
start1+=10;
if(start1+radius1>start2+10)
{
size--;
start2+=200;
setTimeout(function(){
cxt.clearRect(0,0,canvas.width,canvas.height);
cxt.fillStyle=‘red‘;
cxt.beginPath();
cxt.arc(start1,200,radius1,0,Math.PI*2);
cxt.closePath();
cxt.fill();
for(var i=0;i<size;i++)
{
getCircle(start2+i*200,200,radius2,0,‘blue‘)
};
start1+=10;
if(size>0)
{
setTimeout(fn,30)
}else
{
var type = ‘png‘;
var imgData = canvas.toDataURL(type);
document.body.innerHTML=imgData;
var oImg=document.createElement(‘img‘);
oImg.src=imgData;
document.body.appendChild(oImg);
};
},100);
}
else
{
setTimeout(fn,30);
};
};
</script>
</body>
</html>
标签：style io color os ar java for sp on
原文地址：http://www.cnblogs.com/andyjs/p/4064622.html
