获取旋转矩形UIView角点坐标iOS

我正在尝试找到旋转的矩形UIView的四个角的坐标。

我认为我可以做的一种方法是使用识别器。旋转，找到旋转的角度，然后计算起源。 但这需要一些几何计算。

- (IBAction)handlePan:(UIRotationGestureRecognizer*)recognizer { NSLog(@"Rotation in degrees since last change: %f", [recognizer rotation] * (180 / M_PI)); recognizer.view.transform = CGAffineTransformRotate(recognizer.view.transform, recognizer.rotation); NSLog(@"%@",recognizer); recognizer.rotation = 0; NSLog(@"bound is %f and %f, frame is %f and %f, %f and %f.",recognizer.view.bounds.size.width,recognizer.view.bounds.size.height, recognizer.view.frame.size.width,recognizer.view.frame.size.height, recognizer.view.frame.origin.x, recognizer.view.frame.origin.y); } 

我只是想知道是否有其他更简单的方法来获得坐标？ 谢谢！

编辑：

看起来我们在这里有一个很好的答案（见下面的答案）。 我设法通过一种愚蠢的方式计算角落 – 使用旋转角度和几何。 它有效，但不容易和轻松。 我在这里分享我的代码以防万一有人可能想要使用它（即使我怀疑它。）

  float r = 100; NSLog(@"radius is %f.",r); float AAngle = M_PI/3+self.rotatedAngle; float AY = recognizer.view.center.y - sin(AAngle)*r; float AX = recognizer.view.center.x - cos(AAngle)*r; self.pointPADA = CGPointMake(AX, AY); NSLog(@"View Center is (%f,%f)",recognizer.view.center.x,recognizer.view.center.y); NSLog(@"Point A has coordinate (%f,%f)",self.pointPADA.x,self.pointPADA.y); float BAngle = M_PI/3-self.rotatedAngle; float BY = recognizer.view.center.y - sin(BAngle)*r; float BX = recognizer.view.center.x + cos(BAngle)*r; self.pointPADB = CGPointMake(BX, BY); NSLog(@"Point B has coordinate (%f,%f)",BX,BY); float CY = recognizer.view.center.y + sin(AAngle)*r; float CX = recognizer.view.center.x + cos(AAngle)*r; self.pointPADC = CGPointMake(CX, CY); NSLog(@"Point C has coordinate (%f,%f)",CX,CY); float DY = recognizer.view.center.y + sin(BAngle)*r; float DX = recognizer.view.center.x - cos(BAngle)*r; self.pointPADD = CGPointMake(DX, DY); NSLog(@"Point D has coordinate (%f,%f)",DX,DY); 

Answer 1

这是我的解决方案，但我想知道是否有更简洁的方式：

 CGPoint originalCenter = CGPointApplyAffineTransform(theView.center, CGAffineTransformInvert(theView.transform)); CGPoint topLeft = originalCenter; topLeft.x -= theView.bounds.size.width / 2; topLeft.y -= theView.bounds.size.height / 2; topLeft = CGPointApplyAffineTransform(topLeft, theView.transform); CGPoint topRight = originalCenter; topRight.x += theView.bounds.size.width / 2; topRight.y -= theView.bounds.size.height / 2; topRight = CGPointApplyAffineTransform(topRight, theView.transform); CGPoint bottomLeft = originalCenter; bottomLeft.x -= theView.bounds.size.width / 2; bottomLeft.y += theView.bounds.size.height / 2; bottomLeft = CGPointApplyAffineTransform(bottomLeft, theView.transform); CGPoint bottomRight = originalCenter; bottomRight.x += theView.bounds.size.width / 2; bottomRight.y += theView.bounds.size.height / 2; bottomRight = CGPointApplyAffineTransform(bottomRight, theView.transform); 

Answer 2

在Swift 3.1中检查了答案

 struct ViewCorners { private var _topLeft: CGPoint! private var _topRight: CGPoint! private var _bottomLeft: CGPoint! private var _bottomRight: CGPoint! var topLeft: CGPoint { return _topLeft } var topRight: CGPoint { return _topRight } var bottomLeft: CGPoint { return _bottomLeft } var bottomRight: CGPoint { return _bottomRight } private let originalCenter: CGPoint private let transformedView: UIView private func pointWith(multipliedWidth: CGFloat, multipliedHeight: CGFloat) -> CGPoint { var x = originalCenter.x x += transformedView.bounds.width / 2 * multipliedWidth var y = originalCenter.y y += transformedView.bounds.height / 2 * multipliedHeight var result = CGPoint(x: x, y: y).applying(transformedView.transform) result.x += transformedView.transform.tx result.y += transformedView.transform.ty return result } init(view: UIView) { transformedView = view originalCenter = view.center.applying(view.transform.inverted()) _topLeft = pointWith(multipliedWidth:-1, multipliedHeight:-1) _topRight = pointWith(multipliedWidth: 1, multipliedHeight:-1) _bottomLeft = pointWith(multipliedWidth:-1, multipliedHeight: 1) _bottomRight = pointWith(multipliedWidth: 1, multipliedHeight: 1) } }