measurer.WGS84Sphere

measurer.WGS84Sphere is the WGS84 ellipsoid/sphere measurer, mixing in measurer.Common and serving as maptalks' default measurer (sphere radius 6378137). It computes length with the great-circle distance formula and area with the spherical formulation, suitable for most GIS coordinate systems. It is an object mixin with no standalone constructor.

import { measurer } from "maptalks";

const m = measurer.Measurer.getInstance(); // the default WGS84Sphere
m.measureLenBetween([116.39, 39.9], [121.47, 31.23]); // great-circle distance

Properties / Static Methods

• measure: string — The measurer code, 'EPSG:4326'.
• sphere: Sphere — The underlying sphere measurer, radius 6378137.

Methods

• measureLenBetween(c1, c2): number — Great-circle distance (meters).
• measureArea(coords): number — Closed area of a spherical geometry.
• locate(c, xDist, yDist, out?): Coordinate — Locate a coordinate from a source coordinate by x-axis and y-axis distances.
• rotate(c, pivot, angle): Coordinate — Rotate a coordinate around a pivot by a given angle.
• Additionally inherits measureLength from measurer.Common.