好的,我想将 CGPoint(A) 围绕 CGPoint(B) 旋转 50 度,有什么好的方法吗?
CGPoint(A) = CGPoint(x: 50, y: 100)
CGPoint(B) = CGPoint(x: 50, y: 0)
这是我想做的:
最佳答案
这真是一道数学题。在 Swift 中,你想要这样的东西:
func rotatePoint(target: CGPoint, aroundOrigin origin: CGPoint, byDegrees: CGFloat) -> CGPoint {
let dx = target.x - origin.x
let dy = target.y - origin.y
let radius = sqrt(dx * dx + dy * dy)
let azimuth = atan2(dy, dx) // in radians
let newAzimuth = azimuth + byDegrees * CGFloat(M_PI / 180.0) // convert it to radians
let x = origin.x + radius * cos(newAzimuth)
let y = origin.y + radius * sin(newAzimuth)
return CGPoint(x: x, y: y)
}
有很多方法可以简化它,它是 CGPoint
扩展的完美案例,但为了清楚起见,我将其保留得很冗长。
关于swift - 围绕另一个 CGPoint 旋转一个 CGPoint,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/35683376/