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@mappable-world/mappable-web-mercator-projection package

Web Mercator projection package for Mappable JS API.

npm version npm Build Status

projection scheme

Install

You can install this package via npm:

npm install --save @mappable-world/mappable-web-mercator-projection

How use

To use Web Mercator projection, just import it:

import {WebMercator} from '@mappable-world/mappable-web-mercator-projection';

const projection = new WebMercator();

console.log(projection.toWorldCoordinates([-180, 90])) // {x: -1, y: 1}
console.log(projection.toWorldCoordinates([-180, 85.051])) // ~ {x: -1, y: 1}
console.log(projection.toWorldCoordinates([90, 0])) // ~ {x: 0.5, y: 0}
console.log(projection.toWorldCoordinates([0, -23.6])) // ~ {x: 0, y: -0.135}

console.log(projection.fromWorldCoordinates({x: -1, y: 1})) // ~ [-180, 85.051]
console.log(projection.fromWorldCoordinates({x: 0.5, y: 0})) // [90, 0]
console.log(projection.fromWorldCoordinates({x: 0, y: -0.135})) // ~ [0, -23.6]

Usage without npm

You can use some CDN with mappable.import JS API module loading handler on your page:

const {WebMercator} = await mappable.import('@mappable-world/mappable-web-mercator-projection');

NOTE: By default mappable.import can load self modules, scripts or style. To make the code above work, you should add a loader:

// Add loader at the beginning of the loader queue
mappable.import.loaders.unshift(async (pkg) => {
    // Process only this package
    if (!pkg.includes('@mappable-world/mappable-web-mercator-projection')) return;

    // Load script directly. You can use another CDN
    await mappable.import.script(`https://unpkg.com/${pkg}/dist/index.js`);

    // Return result object
    return window['@mappable-world/mappable-web-mercator-projection'];
});