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import {LatLng} from '../LatLng';
import {Bounds} from '../../geometry/Bounds';
import {Point} from '../../geometry/Point';
/*
* @namespace Projection
* @projection L.Projection.SphericalMercator
*
* Spherical Mercator projection — the most common projection for online maps,
* used by almost all free and commercial tile providers. Assumes that Earth is
* a sphere. Used by the `EPSG:3857` CRS.
*/
export var SphericalMercator = {
R: 6378137,
MAX_LATITUDE: 85.0511287798,
project: function (latlng) {
var d = Math.PI / 180,
max = this.MAX_LATITUDE,
lat = Math.max(Math.min(max, latlng.lat), -max),
sin = Math.sin(lat * d);
return new Point(
this.R * latlng.lng * d,
this.R * Math.log((1 + sin) / (1 - sin)) / 2);
},
unproject: function (point) {
var d = 180 / Math.PI;
return new LatLng(
(2 * Math.atan(Math.exp(point.y / this.R)) - (Math.PI / 2)) * d,
point.x * d / this.R);
},
bounds: (function () {
var d = 6378137 * Math.PI;
return new Bounds([-d, -d], [d, d]);
})()
};
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