iphone - 将 CLLocation 移动 x 米

Question

我定义了一个 CLLocation，我想将该点向东移动 x 米，向南移动 y 米。我怎样才能实现这一目标？

Answer 1

到 Swift 的转换，取自 this answer :

func locationWithBearing(bearingRadians:Double, distanceMeters:Double, origin:CLLocationCoordinate2D) -> CLLocationCoordinate2D {
    let distRadians = distanceMeters / (6372797.6) // earth radius in meters

    let lat1 = origin.latitude * M_PI / 180
    let lon1 = origin.longitude * M_PI / 180

    let lat2 = asin(sin(lat1) * cos(distRadians) + cos(lat1) * sin(distRadians) * cos(bearingRadians))
    let lon2 = lon1 + atan2(sin(bearingRadians) * sin(distRadians) * cos(lat1), cos(distRadians) - sin(lat1) * sin(lat2))

    return CLLocationCoordinate2D(latitude: lat2 * 180 / M_PI, longitude: lon2 * 180 / M_PI)
}

Morgan Chen wrote this:

All of the math in this method is done in radians. At the start of themethod, lon1 and lat1 are converted to radians for this purpose aswell. Bearing is in radians too. Keep in mind this method takes intoaccount the curvature of the Earth, which you don't really need to dofor small distances.

我的评论(2021 年 3 月 25 日):

这种方法中使用的计算称为求解“直接测地线问题”，这在 C.F.F. 中进行了讨论。 Karney 的文章“Algorithms for geodesics”，2012 年。上面给出的代码使用的技术不如 Karney 文章中介绍的算法准确。