MKMapView center and zoom in

Question

I am using MKMapView on a project and would like to center the map on a coordinate and zoom in. Just like Google maps has:

GMSCameraPosition.camera(withLatitude:         


        

Answer 1

Base on apinho answer. This option follows Swift 5 syntax and allows to use it as an initializer of MKCoordinateRegion, so can be used in other objects beside MKMapView for example in MKMapSnapshotter.

extension MKCoordinateRegion {

    init(center: CLLocationCoordinate2D, zoom: UInt, bounds: CGRect) {
        let zoom = min(zoom, 20)
        let span = MKCoordinateSpan(center: center, zoom: zoom, bounds: bounds)
        self.init(center: center, span: span)
    }
}

extension MKCoordinateSpan {

    static var mercatorOffset: Double {
        return 268435456.0
    }

    static var mercatorRadius: Double {
        return 85445659.44705395
    }

    private static func longitudeToPixelSpaceX(longitude: Double) -> Double {
        return round(mercatorOffset + mercatorRadius * longitude * Double.pi / 180.0)
    }

    private static func latitudeToPixelSpaceY(latitude: Double) -> Double {
        return round(mercatorOffset - mercatorRadius * log((1 + sin(latitude * Double.pi / 180.0)) / (1 - sin(latitude * Double.pi / 180.0))) / 2.0)
    }

    private static func pixelSpaceXToLongitude(pixelX: Double) -> Double {
        return ((round(pixelX) - mercatorOffset) / mercatorRadius) * 180.0 / Double.pi
    }

    private static func pixelSpaceYToLatitude(pixelY: Double) -> Double {
        return (Double.pi / 2.0 - 2.0 * atan(exp((round(pixelY) - mercatorOffset) / mercatorRadius))) * 180.0 / Double.pi
    }

    init(center: CLLocationCoordinate2D, zoom: UInt, bounds: CGRect) {

        let centerPixelX = MKCoordinateSpan.longitudeToPixelSpaceX(longitude: center.longitude)
        let centerPixelY = MKCoordinateSpan.latitudeToPixelSpaceY(latitude: center.latitude)

        let zoomExponent = Double(20 - zoom)
        let zoomScale = pow(2.0, zoomExponent)

        let mapSizeInPixels = bounds.size
        let scaledMapWidth =  Double(mapSizeInPixels.width) * zoomScale
        let scaledMapHeight = Double(mapSizeInPixels.height) * zoomScale

        let topLeftPixelX = centerPixelX - (scaledMapWidth / 2)
        let topLeftPixelY = centerPixelY - (scaledMapHeight / 2)

        // find delta between left and right longitudes
        let minLng = MKCoordinateSpan.pixelSpaceXToLongitude(pixelX: topLeftPixelX)
        let maxLng = MKCoordinateSpan.pixelSpaceXToLongitude(pixelX: topLeftPixelX + scaledMapWidth)
        let longitudeDelta = maxLng - minLng

        let minLat = MKCoordinateSpan.pixelSpaceYToLatitude(pixelY: topLeftPixelY)
        let maxLat = MKCoordinateSpan.pixelSpaceYToLatitude(pixelY: topLeftPixelY + scaledMapHeight)
        let latitudeDelta = -1 * (maxLat - minLat)

        self.init(latitudeDelta: latitudeDelta, longitudeDelta: longitudeDelta)
    }
}