@id-sdk/geo
Installing
npm install @id-sdk/geo
This library is distributed in ESM format only. It cannot be require()'d from CommonJS.
For more, please read Sindre Sorhus’s FAQ.
import * as geo from '@id-sdk/geo';
import { geoLatToMeters } from '@id-sdk/geo';Contributing
This project is just getting started!
We're not able to support external contributors at this time, but check back in a bit when things have matured.
API Reference
Functions
- geoLatToMeters(dLat: number): number
- geoLonToMeters(dLon: number, atLat: number): number
- geoMetersToLat(m: number): number
- geoMetersToLon(m: number, atLat: number): number
- geoMetersToOffset(m: Vec2, tileSize?: number): Vec2
- geoOffsetToMeters(offset: Vec2, tileSize?: number): Vec2
- geoSphericalDistance(a: Vec2, b: Vec2): number
- geoScaleToZoom(k: number, tileSize?: number): number
- geoZoomToScale(z: number, tileSize?: number): number
- geoSphericalClosestPoint(points: Vec2[], a: Vec2): Closest | null
Types
Functions
# geoLatToMeters(dLat: number): number <>
Convert degrees latitude to meters.
geoLatToMeters(1); // returns ≈111319# geoLonToMeters(dLon: number, atLat: number): number <>
Convert degrees longitude to meters at a given latitude.
geoLonToMeters(1, 0); // returns ≈110946 at equator# geoMetersToLat(m: number): number <>
Convert meters to degrees latitude.
geoMetersToLat(111319); // returns ≈1°# geoMetersToLon(m: number, atLat: number): number <>
Convert meters to degrees longitude at a given latitude.
geoMetersToLon(110946, 0); // returns ≈1° at equator# geoMetersToOffset(m: Vec2, tileSize?: number): Vec2 <>
Convert offset in meters (for example, imagery offset) to offset in tile pixels. tileSize defaults to 256px.
geoMetersToOffset([100, 100]); // returns ≈[0.00064, -0.00064] pixels# geoOffsetToMeters(offset: Vec2, tileSize?: number): Vec2 <>
Convert imagery offset in tile pixels to offset in meters. tileSize defaults to 256px.
geoOffsetToMeters([0.00064, -0.00064]); // returns ≈[100, 100] meters# geoSphericalDistance(a: Vec2, b: Vec2): number <>
Equirectangular approximation of spherical distances on Earth.
geoSphericalDistance([0, 0], [1, 0]); // returns ≈110946 meters# geoScaleToZoom(k: number, tileSize?: number): number <>
Projection scale factor to tile zoom level. tileSize defaults to 256px.
geoScaleToZoom(5340353.7154); // returns ≈17# geoZoomToScale(z: number, tileSize?: number): number <>
Tile zoom to projection scale factor. tileSize defaults to 256px.
geoZoomToScale(17); // returns ≈5340353.7154# geoSphericalClosestPoint(points: Vec2[], a: Vec2): Closest | null <>
Returns info about the point from points closest to the given test point a.
Types
# Vec2
An array of two numbers.
[number, number]
# Closest
An Object containing index, distance, and point properties. Used as the return value for geoSphericalClosestPoint().
{ index: number, distance: number, point: Vec2 }