斯威夫特:尝试旋转绘制的形状?

Question

我在尝试旋转我在以下代码中绘制的形状时遇到问题： 我尝试使用：

triangle.transform = triangle.transform.rotated(by: 3.14159)

但这给了我一个错误"类型为'CATransform3D'的值没有成员'旋转'"。我不确定如何旋转形状。

override func viewDidLoad() {
super.viewDidLoad()
let trianglePath = UIBezierPath()
trianglePath.move(to: CGPoint(x: UIScreen.main.bounds.size.width * 0.5, y: UIScreen.main.bounds.height * 0.5))
trianglePath.addLine(to: CGPoint(x: (UIScreen.main.bounds.size.width * 0.5) + 100, y: (UIScreen.main.bounds.height * 0.5) - 50))
trianglePath.addLine(to: CGPoint(x: (UIScreen.main.bounds.size.width * 0.5) + 100, y: (UIScreen.main.bounds.height * 0.5) + 50))
trianglePath.close()
let triangle = CAShapeLayer()
triangle.path = trianglePath.cgPath
triangle.fillColor = UIColor.gray.cgColor
self.view.layer.addSublayer(triangle)
}

Answer 1

使用它来旋转三角形，您可以使用 useCGAffineTransform

triangle.setAffineTransform(CGAffineTransform(rotationAngle: .pi))

或使用CATransform3D，在 Z 轴上按 pi 旋转

triangle.transform = CATransform3DMakeRotation(.pi, 0, 0, 1)

但是对于这项工作，您还需要调整CAShapeLayer框架

triangle.frame = self.view.bounds //this do the trick

用于显示后的动画

override func viewDidAppear(_ animated: Bool) {
super.viewDidAppear(animated)
UIView.animate(withDuration: 0.1) { 
triangle.setAffineTransform(CGAffineTransform(rotationAngle: .pi)) //this 
triangle.transform = CATransform3DMakeRotation(.pi, 0, 0, 1) //or this
}
}

希望这有帮助