ol/proj/epsg3857.js

OpenLayers mapping library

var __extends = (this && this.__extends) || (function () {
    var extendStatics = function (d, b) {
        extendStatics = Object.setPrototypeOf ||
            ({ __proto__: [] } instanceof Array && function (d, b) { d.__proto__ = b; }) ||
            function (d, b) { for (var p in b) if (b.hasOwnProperty(p)) d[p] = b[p]; };
        return extendStatics(d, b);
    };
    return function (d, b) {
        extendStatics(d, b);
        function __() { this.constructor = d; }
        d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
    };
})();
/**
 * @module ol/proj/epsg3857
 */
import { cosh } from '../math.js';
import Projection from './Projection.js';
import Units from './Units.js';
/**
 * Radius of WGS84 sphere
 *
 * @const
 * @type {number}
 */
export var RADIUS = 6378137;
/**
 * @const
 * @type {number}
 */
export var HALF_SIZE = Math.PI * RADIUS;
/**
 * @const
 * @type {import("../extent.js").Extent}
 */
export var EXTENT = [
    -HALF_SIZE, -HALF_SIZE,
    HALF_SIZE, HALF_SIZE
];
/**
 * @const
 * @type {import("../extent.js").Extent}
 */
export var WORLD_EXTENT = [-180, -85, 180, 85];
/**
 * @classdesc
 * Projection object for web/spherical Mercator (EPSG:3857).
 */
var EPSG3857Projection = /** @class */ (function (_super) {
    __extends(EPSG3857Projection, _super);
    /**
     * @param {string} code Code.
     */
    function EPSG3857Projection(code) {
        return _super.call(this, {
            code: code,
            units: Units.METERS,
            extent: EXTENT,
            global: true,
            worldExtent: WORLD_EXTENT,
            getPointResolution: function (resolution, point) {
                return resolution / cosh(point[1] / RADIUS);
            }
        }) || this;
    }
    return EPSG3857Projection;
}(Projection));
/**
 * Projections equal to EPSG:3857.
 *
 * @const
 * @type {Array<import("./Projection.js").default>}
 */
export var PROJECTIONS = [
    new EPSG3857Projection('EPSG:3857'),
    new EPSG3857Projection('EPSG:102100'),
    new EPSG3857Projection('EPSG:102113'),
    new EPSG3857Projection('EPSG:900913'),
    new EPSG3857Projection('urn:ogc:def:crs:EPSG:6.18:3:3857'),
    new EPSG3857Projection('urn:ogc:def:crs:EPSG::3857'),
    new EPSG3857Projection('http://www.opengis.net/gml/srs/epsg.xml#3857')
];
/**
 * Transformation from EPSG:4326 to EPSG:3857.
 *
 * @param {Array<number>} input Input array of coordinate values.
 * @param {Array<number>=} opt_output Output array of coordinate values.
 * @param {number=} opt_dimension Dimension (default is `2`).
 * @return {Array<number>} Output array of coordinate values.
 */
export function fromEPSG4326(input, opt_output, opt_dimension) {
    var length = input.length;
    var dimension = opt_dimension > 1 ? opt_dimension : 2;
    var output = opt_output;
    if (output === undefined) {
        if (dimension > 2) {
            // preserve values beyond second dimension
            output = input.slice();
        }
        else {
            output = new Array(length);
        }
    }
    var halfSize = HALF_SIZE;
    for (var i = 0; i < length; i += dimension) {
        output[i] = halfSize * input[i] / 180;
        var y = RADIUS *
            Math.log(Math.tan(Math.PI * (+input[i + 1] + 90) / 360));
        if (y > halfSize) {
            y = halfSize;
        }
        else if (y < -halfSize) {
            y = -halfSize;
        }
        output[i + 1] = y;
    }
    return output;
}
/**
 * Transformation from EPSG:3857 to EPSG:4326.
 *
 * @param {Array<number>} input Input array of coordinate values.
 * @param {Array<number>=} opt_output Output array of coordinate values.
 * @param {number=} opt_dimension Dimension (default is `2`).
 * @return {Array<number>} Output array of coordinate values.
 */
export function toEPSG4326(input, opt_output, opt_dimension) {
    var length = input.length;
    var dimension = opt_dimension > 1 ? opt_dimension : 2;
    var output = opt_output;
    if (output === undefined) {
        if (dimension > 2) {
            // preserve values beyond second dimension
            output = input.slice();
        }
        else {
            output = new Array(length);
        }
    }
    for (var i = 0; i < length; i += dimension) {
        output[i] = 180 * input[i] / HALF_SIZE;
        output[i + 1] = 360 * Math.atan(Math.exp(input[i + 1] / RADIUS)) / Math.PI - 90;
    }
    return output;
}
//# sourceMappingURL=epsg3857.js.map