mars-coord/lib/index.js

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"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
exports.convertCoordinate = exports.cgcs2000_to_bd09 = exports.bd09_to_cgcs2000 = exports.cgcs2000_to_gcj02 = exports.gcj02_to_cgcs2000 = exports.wgs84_to_cgcs2000 = exports.cgcs2000_to_wgs84 = exports.bd09_to_gcj02 = exports.gcj02_to_bd09 = exports.gcj02_to_wgs84 = exports.wgs84_to_gcj02 = void 0;
/**
 * The semi-major axis of the Earth, in meters.
 * 地球的半长轴，以米为单位。
 */
const a = 6378245.0;
/**
 * The square of the eccentricity of the Earth's ellipsoid.
 * 地球椭球体离心率的平方。
 */
const ee = 0.00669342162296594323;
/**
 * The mathematical constant pi.
 * 数学常数 π。
 */
const pi = 3.1415926535897932384626;
/**
 * Transform latitude from WGS-84 to GCJ-02
 * 将纬度从WGS-84转换为GCJ-02
 * @param x longitude
 * @param y latitude
 */
function transformLat(x, y) {
    let ret = -100.0 + 2.0 * x + 3.0 * y + 0.2 * y * y + 0.1 * x * y + 0.2 * Math.sqrt(Math.abs(x));
    ret += (20.0 * Math.sin(6.0 * x * pi) + 20.0 * Math.sin(2.0 * x * pi)) * 2.0 / 3.0;
    ret += (20.0 * Math.sin(y * pi) + 40.0 * Math.sin(y / 3.0 * pi)) * 2.0 / 3.0;
    ret += (160.0 * Math.sin(y / 12.0 * pi) + 320.0 * Math.sin(y * pi / 30.0)) * 2.0 / 3.0;
    return ret;
}
/**
 * Transform longitude from WGS-84 to GCJ-02
 * 将经度从WGS-84转换为GCJ-02
 * @param x longitude
 * @param y latitude
 */
function transformLon(x, y) {
    let ret = 300.0 + x + 2.0 * y + 0.1 * x * x + 0.1 * x * y + 0.1 * Math.sqrt(Math.abs(x));
    ret += (20.0 * Math.sin(6.0 * x * pi) + 20.0 * Math.sin(2.0 * x * pi)) * 2.0 / 3.0;
    ret += (20.0 * Math.sin(x * pi) + 40.0 * Math.sin(x / 3.0 * pi)) * 2.0 / 3.0;
    ret += (150.0 * Math.sin(x / 12.0 * pi) + 300.0 * Math.sin(x / 30.0 * pi)) * 2.0 / 3.0;
    return ret;
}
/**
 * Convert from WGS-84 to GCJ-02.
 * 将WGS-84转换为GCJ-02。
 * WGS-84: standard world geodetic system 标准世界地理系统
 * GCJ-02: Chinese national standard used by AMap(高德), Tencent maps(腾讯地图), Google Maps in China etc. 中国国家标准，由高德、腾讯地图、中国谷歌地图等使用。
 */
function wgs84_to_gcj02(coord) {
    let [lng, lat] = coord;
    let dlat = transformLat(lng - 105.0, lat - 35.0);
    let dlon = transformLon(lng - 105.0, lat - 35.0);
    let radlat = lat / 180.0 * pi;
    let magic = Math.sin(radlat);
    magic = 1 - ee * magic * magic;
    let sqrtmagic = Math.sqrt(magic);
    dlat = (dlat * 180.0) / ((a * (1 - ee)) / (magic * sqrtmagic) * pi);
    dlon = (dlon * 180.0) / (a / sqrtmagic * Math.cos(radlat) * pi);
    let mglat = lat + dlat;
    let mglng = lng + dlon;
    return [mglng, mglat];
}
exports.wgs84_to_gcj02 = wgs84_to_gcj02;
/**
 * Convert from GCJ-02 to WGS-84
 * 将GCJ-02转换为WGS-84
 * GCJ-02: Chinese national standard used by AMap(高德), Tencent maps(腾讯地图), Google Maps in China etc. 中国国家标准，由高德、腾讯地图、中国谷歌地图等使用。
 * WGS-84: standard world geodetic system 标准世界地理系统
 */
function gcj02_to_wgs84(coord) {
    let [lng, lat] = coord;
    let dlat = transformLat(lng - 105.0, lat - 35.0);
    let dlon = transformLon(lng - 105.0, lat - 35.0);
    let radlat = lat / 180.0 * pi;
    let magic = Math.sin(radlat);
    magic = 1 - ee * magic * magic;
    let sqrtmagic = Math.sqrt(magic);
    dlat = (dlat * 180.0) / ((a * (1 - ee)) / (magic * sqrtmagic) * pi);
    dlon = (dlon * 180.0) / (a / sqrtmagic * Math.cos(radlat) * pi);
    let mglat = lat - dlat;
    let mglng = lng - dlon;
    return [mglng, mglat];
}
exports.gcj02_to_wgs84 = gcj02_to_wgs84;
/**
 * Convert from GCJ-02 to BD-09
 * GCJ-02: Chinese national standard used by AMap(高德), Tencent maps(腾讯地图), Google Maps in China etc.
 * BD-09: coordinate system used by Baidu Maps(百度地图)
 */
function gcj02_to_bd09(coord) {
    let [lng, lat] = coord;
    let z = Math.sqrt(lng * lng + lat * lat) + 0.00002 * Math.sin(lat * pi);
    let theta = Math.atan2(lat, lng) + 0.000003 * Math.cos(lng * pi);
    let bd_lng = z * Math.cos(theta) + 0.0065;
    let bd_lat = z * Math.sin(theta) + 0.006;
    return [bd_lng, bd_lat];
}
exports.gcj02_to_bd09 = gcj02_to_bd09;
/**
 * Convert from BD-09 to GCJ-02
 * 将BD-09转换为GCJ-02
 * BD-09: coordinate system used by Baidu Maps(百度地图) 百度地图使用的坐标系
 * GCJ-02: Chinese national standard used by AMap(高德), Tencent maps(腾讯地图), Google Maps in China etc. 中国国家标准，由高德、腾讯地图、中国谷歌地图等使用。
 */
function bd09_to_gcj02(coord) {
    let [lng, lat] = coord;
    let x = lng - 0.0065, y = lat - 0.006;
    let z = Math.sqrt(x * x + y * y) - 0.00002 * Math.sin(y * pi);
    let theta = Math.atan2(y, x) - 0.000003 * Math.cos(x * pi);
    let gg_lng = z * Math.cos(theta);
    let gg_lat = z * Math.sin(theta);
    return [gg_lng, gg_lat];
}
exports.bd09_to_gcj02 = bd09_to_gcj02;
// CGCS2000 and WGS-84 are very similar, with typical errors of less than 1 meter, so they can be considered equivalent here
// CGCS2000和WGS-84非常相似，典型误差小于1米，因此可以在这里被认为是等效的
/**
 * Convert from CGCS2000 to WGS-84
 * 将CGCS2000转换为WGS-84
 */
const cgcs2000_to_wgs84 = (coord) => coord;
exports.cgcs2000_to_wgs84 = cgcs2000_to_wgs84;
/**
 * Convert from WGS-84 to CGCS2000
 * 将WGS-84转换为CGCS2000
 */
const wgs84_to_cgcs2000 = (coord) => coord;
exports.wgs84_to_cgcs2000 = wgs84_to_cgcs2000;
/**
 * Convert from GCJ-02 to CGCS2000
 * 将GCJ-02转换为CGCS2000
 */
exports.gcj02_to_cgcs2000 = exports.wgs84_to_cgcs2000;
/**
 * Convert from CGCS2000 to GCJ-02
 * 将CGCS2000转换为GCJ-02
 */
exports.cgcs2000_to_gcj02 = gcj02_to_wgs84;
/**
 * Convert from BD-09 to CGCS2000
 * 将BD-09转换为CGCS2000
 */
const bd09_to_cgcs2000 = (coord) => (0, exports.wgs84_to_cgcs2000)(gcj02_to_wgs84(bd09_to_gcj02(coord)));
exports.bd09_to_cgcs2000 = bd09_to_cgcs2000;
/** Convert from CGCS2000 to BD-09 */
const cgcs2000_to_bd09 = (coord) => gcj02_to_bd09(wgs84_to_gcj02((0, exports.cgcs2000_to_wgs84)(coord)));
exports.cgcs2000_to_bd09 = cgcs2000_to_bd09;
/**
 * Convert coordinates from one type to all
 * 将坐标从一种类型转换为所有类型
 * @param coord Coordinates to convert 需要转换的坐标
 * @param coordType Type of coordinates 坐标类型
 * @returns All coordinates 所有坐标
 */
function convertCoordinate(coord, coordType) {
    let WGS84;
    let GCJ02;
    let BD09;
    let CGCS2000;
    switch (coordType) {
        case 'WGS84':
            WGS84 = coord;
            GCJ02 = wgs84_to_gcj02(coord);
            BD09 = gcj02_to_bd09(GCJ02);
            CGCS2000 = (0, exports.wgs84_to_cgcs2000)(coord);
            break;
        case 'GCJ02':
        case 'AMAP':
        case 'QQ':
            GCJ02 = coord;
            WGS84 = gcj02_to_wgs84(coord);
            BD09 = gcj02_to_bd09(coord);
            CGCS2000 = (0, exports.gcj02_to_cgcs2000)(coord);
            break;
        case 'BD09':
        case 'BAIDU':
            BD09 = coord;
            GCJ02 = bd09_to_gcj02(coord);
            WGS84 = gcj02_to_wgs84(GCJ02);
            CGCS2000 = (0, exports.bd09_to_cgcs2000)(coord);
            break;
        case 'CGCS2000':
            CGCS2000 = coord;
            WGS84 = (0, exports.cgcs2000_to_wgs84)(coord);
            GCJ02 = (0, exports.cgcs2000_to_gcj02)(coord);
            BD09 = (0, exports.cgcs2000_to_bd09)(coord);
            break;
    }
    return {
        WGS84,
        GCJ02,
        AMAP: GCJ02,
        QQ: GCJ02,
        BD09,
        BAIDU: BD09,
        CGCS2000
    };
}
exports.convertCoordinate = convertCoordinate;