geodesicUtils

Method Overview

Method Details

geodesicAreas(polygons, unit){Number[]}static

Geodetically computes the area for one or more polygons.

Parameters:

polygons Polygon[] The polygons to compute the area for.

unit String optional Default Value: "square-meters" Output area units. Possible Values:"square-millimeters"|"square-centimeters"|"square-decimeters"|"square-meters"|"square-kilometers"|"square-inches"|"square-feet"|"square-yards"|"square-miles"|"square-us-feet"|"acres"|"ares"|"hectares"

Returns:

Type	Description
Number[]	An array of areas corresponding to the source polygons.

Example:

// Display the area of the Bermuda Triangle.
const MIAMI    = { lat: 25.775278, lon: -80.208889 };  // Florida
const HAMILTON = { lat: 32.293, lon: -64.782 };        // Bermuda
const SANJUAN  = { lat: 18.406389, lon:  -66.063889 }; // Puerto Rico
const polygon = new Polygon({
  rings: [[
    [MIAMI.lon, MIAMI.lat],
    [HAMILTON.lon, HAMILTON.lat],
    [SANJUAN.lon, SANJUAN.lat],
    [MIAMI.lon, MIAMI.lat]
  ]]
});
const areas = geodesicUtils.geodesicAreas([polygon], "square-kilometers");
const area = Math.round(areas[0]);
console.log("Area: ", area, " km²"); // Area: 1150498 km²

geodesicDensify(geometry, maxSegmentLength){Polyline|Polygon}static

Computes and returns a densified polyline or polygon.

Parameters:

geometry Polyline|Polygon The input polyline or polygon.

maxSegmentLength Number The maximum length (in meters) between vertices.

Returns:

Type	Description
Polyline | Polygon	The densified polyline or polygon.

Example:

// Densify the polygon representing Bermuda Triangle with maximum segment size of 100km.
const MIAMI    = { lat: 25.775278, lon: -80.208889 };  // Florida
const HAMILTON = { lat: 32.293, lon: -64.782 };        // Bermuda
const SANJUAN  = { lat: 18.406389, lon:  -66.063889 }; // Puerto Rico
const polygon = new Polygon({
  rings: [[
    [MIAMI.lon, MIAMI.lat],
    [HAMILTON.lon, HAMILTON.lat],
    [SANJUAN.lon, SANJUAN.lat],
    [MIAMI.lon, MIAMI.lat]
  ]]
});
const densifiedPolygon = geodesicUtils.geodesicDensify(polygon, 100000);
const vertexCountBefore = polygon.rings[0].length;
const vertexCountAfter = densifiedPolygon.rings[0].length;
console.log("Before: ", vertexCountBefore, ", After: ", vertexCountAfter); // Before: 4, After: 51

geodesicDistance(from, to, unit){GeodesicDistanceResult}static

Geodetically computes the direction and distance between two known locations. Both input points must have the same geographic coordinate system.

Parameters:

from Point The origin location.

to Point The destination location.

unit String optional Default Value: "meters" Output linear units. Possible Values:"millimeters"|"centimeters"|"decimeters"|"meters"|"kilometers"|"inches"|"feet"|"yards"|"miles"|"nautical-miles"|"us-feet"

Returns:

Type	Description
GeodesicDistanceResult	Computed distance and direction between the two known locations. Name Type Description distance number The distance between the two locations. azimuth number The azimuth (or "bearing") in degrees. Values range from 0° to 360°. reverseAzimuth number The reverse azimuth in degrees. Values range from 0° to 360°.

Example:

// Display the distance and direction between Los Angeles and New York City.
const LA = {
  latitude: 34.05,
  longitude: -118.25
};
const NY = {
  latitude: 40.7127,
  longitude: -74.0059
};
const join = geodesicUtils.geodesicDistance(
  new Point({ x: LA.longitude, y: LA.latitude }),
  new Point({ x: NY.longitude, y: NY.latitude }),
  "kilometers"
);
const { distance, azimuth } = join;
console.log("Distance: ", distance, ", Direction: ", azimuth);

geodesicLengths(geometries, unit){Number[]}static

Geodetically computes polygon perimeter or polyline length for one or more geometries.

Parameters:

geometries Polyline[]|Polygon[] The input polylines or polygons.

unit String optional Default Value: "meters" Output linear units. Possible Values:"millimeters"|"centimeters"|"decimeters"|"meters"|"kilometers"|"inches"|"feet"|"yards"|"miles"|"nautical-miles"|"us-feet"

Returns:

Type	Description
Number[]	An array of lengths/perimeters corresponding to the input geometries.

Example:

// Display the perimeter of the Bermuda Triangle.
const MIAMI    = { lat: 25.775278, lon: -80.208889 };  // Florida
const HAMILTON = { lat: 32.293, lon: -64.782 };        // Bermuda
const SANJUAN  = { lat: 18.406389, lon:  -66.063889 }; // Puerto Rico
const polygon = new Polygon({
  rings: [[
    [MIAMI.lon, MIAMI.lat],
    [HAMILTON.lon, HAMILTON.lat],
    [SANJUAN.lon, SANJUAN.lat],
    [MIAMI.lon, MIAMI.lat]
  ]]
});
const perimeters = geodesicUtils.geodesicLengths([polygon], "kilometers");
const perimeter = Math.round(perimeters[0]);
console.log("Perimeter: ", perimeter, " km"); // Perimeter: 4879 km

pointFromDistance(point, distance, azimuth){Point}static

Geodetically computes the location at a defined distance and direction from a known location.

Parameters:

point Point Origin location.

distance Number Distance from the origin in meters.

azimuth Number Direction from the origin in degrees.

Returns:

Type	Description
Point	The computed point.

Example:

// Display the location of a point 10km East of Los Angeles.
const LA = {
  latitude: 34.05,
  longitude: -118.25
};
const destination = geodesicUtils.pointFromDistance(
  new Point({ x: LA.longitude, y: LA.latitude }),
  10000,
  90
);
const { latitude, longitude } = destination;
console.log("Latitude: ", latitude, ", Longitude: ", longitude);

Type Definitions

GeodesicDistanceResult

Computed distance and direction between two known locations.

Properties:

distance Number optional The distance between the two locations.

azimuth Number optional The azimuth (or "bearing") in degrees. Value will be in the range of 0-360°.

reverseAzimuth Number optional The azimuth in degrees in the reverse direction. Value will be in the range of 0-360°.