Context.beginPath();
Context.arc(x,y,radius,startAngle,endAngle,anticlockwise);(for循环圆心、半径)
Context.closePath();
Context.fillStyle=’rgba(255,0,0,0.25)’
Context.fill()
ellipse(x,y,radiusX,radiusY,rotation,startAngle,endAngle,anticlockwise)
- <head>
- <meta charset="UTF-8">
- <title>圆-椭圆</title>
- <meta name="viewport" content="width=device-width,initial-scale=1,minimum-scale=1,maximum-scale=1,user-scalable=no" />
- </head>
- <body>
- <canvas id="canvas" width="500" height="500"></canvas>
- <script type="text/javascript">
- var oCanvas = document.getElementById("canvas");
- var context = oCanvas.getContext("2d");
- context.fillStyle = "#ededed";
- context.fillRect(, , , );
- //画圆第一个
- context.beginPath(); //开始圆
- context.arc(, , , , * Math.PI, true); //50半径,Math.PI圆的π,true顺时针
- context.closePath(); // 关闭圆,然后回到起点
- context.fillStyle = "rgba(255,0,0,0.5)"; //颜色,0.5透明度
- context.fill(); //填充这个圆
- for(var i = ; i < ; i++) {
- context.beginPath(); //开始圆
- context.arc(i*, i*, i*, , * Math.PI, true); //50半径,Math.PI圆的π,true顺时针
- context.closePath(); // 关闭圆,然后回到起点
- context.fillStyle = "rgba(255,0,0,0.5)"; //颜色
- context.fill(); //填充这个圆
- }
- //椭圆
- context.beginPath();
- context.ellipse(, , , , 0.5, , *Math.PI, true);//radiusX:x方向上半径,radiusY:x方向上半径,0.5:rotation:旋转角度
- context.closePath();
- context.fillStyle = "#06e";
- context.fill();
- </script>
- </body>
- </html>
以上就是HTML5之canvas-2圆 椭圆的详细内容,更多关于HTML5之canvas-2圆 椭圆的资料请关注九品源码其它相关文章!