如何使用 Swift 将 Mapbox 缩放到以千米为单位的给定半径？

Question

我最近从旧版 Mapbox SDK（版本 1.6）更新到最新的 Mapbox iOS SDK 3.x。

在新版本中，我无法弄清楚如何将 Mapbox MGLMapView 缩放到以公里为单位的给定半径以适合屏幕。

在旧版本（1.6 版）中，RMMapView.zoomWithLatitudeLongitudeBoundsSouthWest 方法的工作如下：

func centerAndZoom(center: CLLocationCoordinate2D, kilometers: Float) {
    let meters = Double(kilometers * 1000)
    let region = MKCoordinateRegionMakeWithDistance(center, meters / 2, meters / 2);

    let northEastLat = center.latitude - (region.span.latitudeDelta / 2);
    let northEastLon = center.longitude + (region.span.longitudeDelta / 2);
    let northEast = CLLocationCoordinate2D(latitude: northEastLat, longitude: northEastLon)

    let southEastLat = center.latitude + (region.span.latitudeDelta  / 2);
    let southEastLon = center.longitude - (region.span.longitudeDelta / 2);
    let southEast = CLLocationCoordinate2D(latitude: southEastLat, longitude: southEastLon)

    self.mapView.zoomWithLatitudeLongitudeBoundsSouthWest(southEast, northEast: northEast, animated: true)
}

如何使用Swift在最新的Mapbox中实现半径缩放？

Answer 1

现在 -setVisibleCoordinateBounds:animated 将完成这项工作：

Changes the receiver’s viewport to fit the given coordinate bounds, optionally animating the change.

Mapbox iOS SDK Reference

这是一个例子：

let bounds = MGLCoordinateBounds(
        sw: CLLocationCoordinate2D(latitude: 43.7115, longitude: 10.3725),
        ne: CLLocationCoordinate2D(latitude: 43.7318, longitude: 10.4222))
mapView.setVisibleCoordinateBounds(bounds, animated: false)

Answer 2

以下是我如何从给定坐标缩放到特定半径：

let center = CLLocationCoordinate2D(latitude: <#T##CLLocationDegrees#>, longitude: <#T##CLLocationDegrees#>)
let kilometers: Double = 2.0
let halfMeters = (kilometers * 1000) / 2
let region = MKCoordinateRegionMakeWithDistance(center, halfMeters, halfMeters)
let southWest = CLLocationCoordinate2D(
    latitude: center.latitude - (region.span.latitudeDelta  / 2),
    longitude: center.longitude - (region.span.longitudeDelta / 2)
)
let northEast = CLLocationCoordinate2D(
    latitude: center.latitude + (region.span.latitudeDelta  / 2),
    longitude: center.longitude + (region.span.longitudeDelta / 2)
)

let bounds = MGLCoordinateBounds(sw: southWest, ne: northEast)
mapView.setVisibleCoordinateBounds(bounds, edgePadding: .zero, animated: false)

如何使用 Swift 将 Mapbox 缩放到以千米为单位的给定半径？

How to zoom Mapbox using Swift to a given radius in kilometers?

ios

mapbox

swift