MGLPolyline


@interface MGLPolyline : MGLMultiPoint <MGLOverlay>

An MGLPolyline object represents a shape consisting of two or more vertices, specified as CLLocationCoordinate2D instances, and the line segments that connect them. For example, you could use an polyline to represent a road or the path along which something moves.

You can add polyline shapes to the map by adding them to an MGLShapeSource object. Configure the appearance of an MGLShapeSource’s or MGLVectorSource’s polylines collectively using an MGLLineStyleLayer or MGLSymbolStyleLayer object.

Alternatively, you can add a polyline overlay directly to a map view using the -[MGLMapView addAnnotation:] or -[MGLMapView addOverlay:] method. Configure a polyline overlay’s appearance using -[MGLMapViewDelegate mapView:strokeColorForShapeAnnotation:] and -[MGLMapViewDelegate mapView:lineWidthForPolylineAnnotation:].

The vertices are automatically connected in the order in which you provide them. The first and last vertices are not connected to each other, but you can specify the same CLLocationCoordinate2D as the first and last vertices in order to close the polyline. To fill the space within the shape, use an MGLPolygon object. To group multiple polylines together in one shape, use an MGLMultiPolyline or MGLShapeCollection object.

To make the polyline go across the antimeridian or international date line, specify some longitudes less than −180 degrees or greater than 180 degrees. For example, a polyline that stretches from Tokyo to San Francisco would have coordinates of (35.68476, -220.24257) and (37.78428, -122.41310).

let coordinates = [
    CLLocationCoordinate2D(latitude: 35.68476, longitude: -220.24257),
    CLLocationCoordinate2D(latitude: 37.78428, longitude: -122.41310)
]
let polyline = MGLPolyline(coordinates: coordinates, count: UInt(coordinates.count))

A polyline is known as a LineString geometry in GeoJSON.

  • Creates and returns an MGLPolyline object from the specified set of coordinates.

    Declaration

    Objective-C

    + (nonnull instancetype)polylineWithCoordinates:
                                (nonnull const CLLocationCoordinate2D *)coords
                                              count:(NSUInteger)count;

    Swift

    convenience init(coordinates coords: UnsafePointer<CLLocationCoordinate2D>, count: UInt)

    Parameters

    coords

    The array of coordinates defining the shape. The data in this array is copied to the new object.

    count

    The number of items in the coords array.

    Return Value

    A new polyline object.