iOS画圆

/* Add an arc of a circle to the context‘s path, possibly preceded by a

   straight line segment. `(x, y)‘ is the center of the arc; `radius‘ is its

   radius; `startAngle‘ is the angle to the first endpoint of the arc;

   `endAngle‘ is the angle to the second endpoint of the arc; and

   `clockwise‘ is 1 if the arc is to be drawn clockwise, 0 otherwise.

   `startAngle‘ and `endAngle‘ are measured in radians. */

  ”(x,y)”是弧的中心,“radius”是它的半径;“startAngle”是第一个的角弧的端点;“endAngle”的第二个端点弧角;和

  “clockwise” == 1电弧是顺时针,否则为0。

  “startAngle”和“endAngle测量的弧度。

 CG_EXTERN void CGContextAddArc(CGContextRef c, CGFloat x, CGFloat y,

  CGFloat radius, CGFloat startAngle, CGFloat endAngle, int clockwise)

  CG_AVAILABLE_STARTING(__MAC_10_0, __IPHONE_2_0);

 

 CGContextAddArc(context, x, y, 3, 0, 2*PI, 0); //添加一个圆   圆心为(x, y)半径为3 圆周为2*PI的小圆,

郑重声明:本站内容如果来自互联网及其他传播媒体,其版权均属原媒体及文章作者所有。转载目的在于传递更多信息及用于网络分享,并不代表本站赞同其观点和对其真实性负责,也不构成任何其他建议。