确定纬度/经度点是否在Mapview中的MKPolygon中

Question

此时，我正试图弄清楚MKMapView上的坐标是否在提前绘制的具有纬度/经度的MKPolygon内。

我使用CGPathContainsPoint来确定坐标是否在地图上的多边形内，但无论我选择的坐标如何，它总是返回false。

谁能解释一下到底是哪里出了问题?下面是我在Swift中的代码。

class ViewController: UIViewController, MKMapViewDelegate
@IBOutlet weak var mapView: MKMapView!
    let initialLocation = CLLocation(latitude: 43.656734, longitude: -79.381576)
    let point = CGPointMake(43.656734, -79.381576)
    let regionRadius: CLLocationDistance = 500
    let point1 = CLLocationCoordinate2D(latitude: 43.656734, longitude: -79.381576)
    var points = [CLLocationCoordinate2DMake(43.655782, -79.382094),
        CLLocationCoordinate2DMake(43.657499, -79.382310),
        CLLocationCoordinate2DMake(43.656656, -79.380497),
        CLLocationCoordinate2DMake(43.655782, -79.382094)]
    override func viewDidLoad() {
        super.viewDidLoad()
        centerMapOnLocation(initialLocation)
        let polygon = MKPolygon(coordinates: &points, count: points.count)
        mapView.addOverlay(polygon)
        var annotation = MKPointAnnotation()
        annotation.coordinate = point1
        annotation.title = "Test"
        annotation.subtitle = "Test"
        mapView.addAnnotation(annotation)
        self.mapView.delegate = self
    }
    func centerMapOnLocation(location: CLLocation) {
        let coordinateRegion = MKCoordinateRegionMakeWithDistance(location.coordinate, regionRadius * 2.0, regionRadius * 2.0)
        mapView.setRegion(coordinateRegion, animated: true)
    }
    func mapView(mapView: MKMapView!, rendererForOverlay overlay: MKOverlay!) -> MKOverlayRenderer! {
        if overlay is MKPolygon {
            let polygonView = MKPolygonRenderer(overlay: overlay)
            polygonView.strokeColor = UIColor.redColor()
            if  CGPathContainsPoint(polygonView.path, nil, CGPointMake(43.656734, -79.381576), true) {
                print("True!!!!!")
            } else {
                println("False")
            }
            return polygonView
        }
        return nil
    }

Answer 1

已更新为SWIFT 4

你混淆了CGPoints，它是x和y坐标对，指向视图中的位置，与cllocationcoordinate2d，这是地球上的坐标。

对于CGPathContainsPoint，你想传递你的polygonRenderer路径(从你的多边形在viewDidLoad()中创建)和当前位置，像这样:

let polygonRenderer = MKPolygonRenderer(polygon: polygon)
let mapPoint: MKMapPoint = MKMapPointForCoordinate(coordinate)
let polygonViewPoint: CGPoint = polygonRenderer.pointForMapPoint(mapPoint)
if polygonRenderer.path.contains(polygonViewPoint) {
    print("Your location was inside your polygon.")
}

所以你要考虑你应该把这段代码放在哪里，因为你现在有它在函数中，当MKOverlay被绘制到屏幕上时被调用，这是完全无关的。

Answer 2

已更新为Swift 3

let polygonRenderer = MKPolygonRenderer(polygon: polygon)
let mapPoint: MKMapPoint = MKMapPointForCoordinate(coordinate)
let polygonViewPoint: CGPoint = polygonRenderer.point(for: mapPoint)
if polygonRenderer.path.contains(polygonViewPoint)
{
    print("Your location was inside your polygon.")
}

Answer 3

Swift 5解决方案:

因为渲染器。路径的包含方法需要点作为CGPoint，我们需要通过MKMapPoint将它从地理坐标转换为rederer的点，否则结果将是意想不到的。

@objc
func mapTapped(_ tap: UILongPressGestureRecognizer) {
    if tap.state == .recognized {
        let touchPoint = tap.location(in: mapView)
        let coord = mapView.convert(touchPoint, toCoordinateFrom: mapView)
        for overlay: MKOverlay in mapView.overlays {
            if let polygon = overlay as? MKPolygon {
                let renderer = MKPolygonRenderer(polygon: polygon)
                let mapPoint = MKMapPoint(coord)
                let rendererPoint = renderer.point(for: mapPoint)
                if renderer.path.contains(rendererPoint) {
                    // here comes your code
                }
            }
        }
    }
}

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