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.