效果圖:
基本原理[圖來自官方文檔]:
當前點[current point]、控制點[control point]和結束點[endPoint]之間的關系定義了實際的曲線。
函數代碼實例:
#pragma mark畫二次貝塞爾曲線
-(void)secondBeziePathDraw
{
UIBezierPath*path=[UIBezierPathbezierPath];
//起點[左側]
[pathmoveToPoint:CGPointMake(20,self.frame.size.height-100)];
//二次曲線
[pathaddQuadCurveToPoint:CGPointMake(self.frame.size.width-30,self.frame.size.height-100)controlPoint:CGPointMake(self.frame.size.width/2,self.frame.size.height-10)];
path.lineWidth=8;
UIColor*sColor=[UIColorredColor];
[sColorset];
[pathstroke];
}