LngLat

A LngLat object represents a given longitude and latitude coordinate, measured in degrees. These coordinates are based on the WGS84 (EPSG:4326) standard.

MapLibre GL JS uses longitude, latitude coordinate order (as opposed to latitude, longitude) to match the GeoJSON specification.

Note that any MapLibre GL JS method that accepts a LngLat object as an argument or option can also accept an Array of two numbers and will perform an implicit conversion. This flexible type is documented as LngLatLike.

Example

let ll = new LngLat(-123.9749, 40.7736);
ll.lng; // = -123.9749

See

Get coordinates of the mouse pointer

Constructors

Constructor

new LngLat(lng: number, lat: number): LngLat

Parameters

Returns

LngLat

Methods

distanceTo()

distanceTo(lngLat: LngLat): number

Returns the approximate distance between a pair of coordinates in meters Uses the Haversine Formula (from R.W. Sinnott, "Virtues of the Haversine", Sky and Telescope, vol. 68, no. 2, 1984, p. 159)

Parameters

Returns

number

Distance in meters between the two coordinates.

Example

let new_york = new LngLat(-74.0060, 40.7128);
let los_angeles = new LngLat(-118.2437, 34.0522);
new_york.distanceTo(los_angeles); // = 3935751.690893987, "true distance" using a non-spherical approximation is ~3966km

toArray()

toArray(): [number, number]

Returns the coordinates represented as an array of two numbers.

Returns

[number, number]

The coordinates represented as an array of longitude and latitude.

Example

let ll = new LngLat(-73.9749, 40.7736);
ll.toArray(); // = [-73.9749, 40.7736]

toString()

toString(): string

Returns the coordinates represent as a string.

Returns

string

The coordinates represented as a string of the format 'LngLat(lng, lat)'.

Example

let ll = new LngLat(-73.9749, 40.7736);
ll.toString(); // = "LngLat(-73.9749, 40.7736)"

wrap()

wrap(): LngLat

Returns a new LngLat object whose longitude is wrapped to the range (-180, 180).

Returns

LngLat

The wrapped LngLat object.

Example

let ll = new LngLat(286.0251, 40.7736);
let wrapped = ll.wrap();
wrapped.lng; // = -73.9749

convert()

static convert(input: LngLatLike): LngLat

Converts an array of two numbers or an object with lng and lat or lon and lat properties to a LngLat object.

If a LngLat object is passed in, the function returns it unchanged.

Parameters

Returns

LngLat

A new LngLat object, if a conversion occurred, or the original LngLat object.

Example

let arr = [-73.9749, 40.7736];
let ll = LngLat.convert(arr);
ll;   // = LngLat {lng: -73.9749, lat: 40.7736}

Properties

lat

lat: number

Latitude, measured in degrees.

lng

lng: number

Longitude, measured in degrees.