@sparta-utils/gps-transform-utils/dist/transformer.js

一个支持三参数与七参数的 GPS 坐标转换工具，适用于 WGS84 转 CGCS2000、北京54 等坐标系的正向与反向平面投影计算。

import proj4 from 'proj4';
/**
 * 自动获取中央经线（三度带）
 */
function getDefaultCentralMeridian(lng, zoneWidth) {
    if (zoneWidth === void 0) { zoneWidth = 3; }
    var zone = Math.floor(lng / zoneWidth) + 1;
    return zone * zoneWidth;
}
/**
 * 构建 proj4 投影字符串
 */
function buildProjString(coordSystem, centralMeridian, towgs84) {
    var parts = [
        '+proj=tmerc',
        '+lat_0=0',
        "+lon_0=".concat(centralMeridian),
        '+k=1.0',
        '+x_0=500000',
        '+y_0=0',
        coordSystem === 'CGCS2000' ? '+ellps=GRS80' : '+a=6378245.0',
        coordSystem === '北京54' ? '+b=6356863.0188' : '',
        "+towgs84=".concat(towgs84),
        '+units=m',
        '+no_defs'
    ];
    return parts.filter(Boolean).join(' ');
}
/**
 * GPS → 平面（3参数）
 */
export function gpsToPlaneBy3Params(coordSystem, params, gps, centralMeridian) {
    var cm = centralMeridian !== null && centralMeridian !== void 0 ? centralMeridian : getDefaultCentralMeridian(gps.lng);
    var towgs84 = "".concat(params.dx, ",").concat(params.dy, ",").concat(params.dz);
    var projDef = buildProjString(coordSystem, cm, towgs84);
    var _a = proj4('EPSG:4326', projDef, [gps.lng, gps.lat]), x = _a[0], y = _a[1];
    return { x: parseFloat(x.toFixed(3)), y: parseFloat(y.toFixed(3)) };
}
/**
 * GPS → 平面（7参数）
 */
export function gpsToPlaneBy7Params(coordSystem, params, gps, centralMeridian) {
    var cm = centralMeridian !== null && centralMeridian !== void 0 ? centralMeridian : getDefaultCentralMeridian(gps.lng);
    var dx = params.dx, dy = params.dy, dz = params.dz, rx = params.rx, ry = params.ry, rz = params.rz, scale = params.scale;
    var towgs84 = "".concat(dx, ",").concat(dy, ",").concat(dz, ",").concat(rx, ",").concat(ry, ",").concat(rz, ",").concat(scale);
    var projDef = buildProjString(coordSystem, cm, towgs84);
    var _a = proj4('EPSG:4326', projDef, [gps.lng, gps.lat]), x = _a[0], y = _a[1];
    return { x: parseFloat(x.toFixed(3)), y: parseFloat(y.toFixed(3)) };
}
/**
 * 平面 → GPS 坐标（反向投影）
 */
export function planeToGps(coordSystem, params, xy, centralMeridian, isSevenParam) {
    if (isSevenParam === void 0) { isSevenParam = false; }
    var towgs84 = isSevenParam
        ? "".concat(params.dx, ",").concat(params.dy, ",").concat(params.dz, ",").concat(params.rx, ",").concat(params.ry, ",").concat(params.rz, ",").concat(params.scale)
        : "".concat(params.dx, ",").concat(params.dy, ",").concat(params.dz);
    var projDef = buildProjString(coordSystem, centralMeridian, towgs84);
    var _a = proj4(projDef, 'EPSG:4326', [xy.x, xy.y]), lng = _a[0], lat = _a[1];
    return { lng: parseFloat(lng.toFixed(8)), lat: parseFloat(lat.toFixed(8)) };
}