MLNPolygon class

An MLNPolygon object represents a closed shape consisting of four or more vertices, specified as CLLocationCoordinate2D instances, and the edges that connect them. For example, you could use a polygon shape to represent a building, a lake, or an area you want to highlight.

You can add polygon shapes to the map by adding them to an MLNShapeSource object. Configure the appearance of an MLNShapeSource’s or MLNVectorTileSource’s polygons collectively using an MLNVectorTileSource or MLNSymbolStyleLayer object. To access a polygon’s attributes, use an MLNPolygonFeature object.

Alternatively, you can add a polygon overlay directly to a map view using the MLNMapView/addAnnotation: or MLNMapView/addOverlay: method. Configure a polygon overlay’s appearance using MLNMapViewDelegate/mapView:strokeColorForShapeAnnotation: and MLNMapViewDelegate/mapView:fillColorForPolygonAnnotation:.

The vertices are automatically connected in the order in which you provide them. You should close the polygon by specifying the same CLLocationCoordinate2D as the first and last vertices; otherwise, the polygon’s fill may not cover the area you expect it to. To avoid filling the space within the shape, give the polygon a transparent fill or use an MLNPolyline object.

A polygon may have one or more interior polygons, or holes, that you specify as MLNPolygon objects with the +polygonWithCoordinates:count:interiorPolygons: method. For example, if a polygon represents a lake, it could exclude an island within the lake using an interior polygon. Interior polygons may not themselves have interior polygons. To represent a shape that includes a polygon within a hole or, more generally, to group multiple polygons together in one shape, use an MLNMultiPolygon or MLNMultiPolygon object.

To make the polygon straddle the antimeridian, specify some longitudes less than −180 degrees or greater than 180 degrees.

Related examples

TODO: Add a polygon annotation, learn how to initialize an MLNPolygon object from an array of coordinates.