html5 canvas贝塞尔曲线篇(上)

<!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">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>html5 canvas贝塞尔曲线篇</title>
<script src="js/modernizr.js"></script>
</head>

<body>
<h1>html5 canvas贝塞尔曲线篇</h1>

<script type="text/javascript">
window.addEventListener('load',eventWindowLoaded,false);
function eventWindowLoaded(){
	canvasApp();
}
function canvasSupport(){
	return Modernizr.canvas;
}
function canvasApp(){
	if(!canvasSupport()){
		return;
	}else{
		var theCanvas = document.getElementById('canvas')
		var context = theCanvas.getContext("2d")

	}
	drawScreen();
    function drawScreen(){
		//颜色粉色,线宽10,
	     context.beginPath();
	     context.strokeStyle="red";
             context.lineWidth=2;
		 context.moveTo(0,0);  //从0,0开始
		 
		 //context.quadraticCurveTo(cpx,cpy,x,y);
		 
		 context.quadraticCurveTo(200,50,0,100);  //0,100结束,创建弧线的点位于(200,25)
		 context.stroke();
		 context.closePath();
		 
	}
}


</script>
<canvas id="canvas" width="500" height="500">
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</canvas>
</body>
</html>

 //context.quadraticCurveTo(cpx,cpy,x,y);

说明在代码内有注释哦

原文地址:https://www.cnblogs.com/LoveOrHate/p/4390249.html