tethys-feature-service/node_modules/proj4/lib/datum.js

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2023-10-02 13:04:02 +00:00
import {PJD_3PARAM, PJD_7PARAM, PJD_GRIDSHIFT, PJD_WGS84, PJD_NODATUM, SEC_TO_RAD} from './constants/values';
function datum(datumCode, datum_params, a, b, es, ep2, nadgrids) {
var out = {};
if (datumCode === undefined || datumCode === 'none') {
out.datum_type = PJD_NODATUM;
} else {
out.datum_type = PJD_WGS84;
}
if (datum_params) {
out.datum_params = datum_params.map(parseFloat);
if (out.datum_params[0] !== 0 || out.datum_params[1] !== 0 || out.datum_params[2] !== 0) {
out.datum_type = PJD_3PARAM;
}
if (out.datum_params.length > 3) {
if (out.datum_params[3] !== 0 || out.datum_params[4] !== 0 || out.datum_params[5] !== 0 || out.datum_params[6] !== 0) {
out.datum_type = PJD_7PARAM;
out.datum_params[3] *= SEC_TO_RAD;
out.datum_params[4] *= SEC_TO_RAD;
out.datum_params[5] *= SEC_TO_RAD;
out.datum_params[6] = (out.datum_params[6] / 1000000.0) + 1.0;
}
}
}
if (nadgrids) {
out.datum_type = PJD_GRIDSHIFT;
out.grids = nadgrids;
}
out.a = a; //datum object also uses these values
out.b = b;
out.es = es;
out.ep2 = ep2;
return out;
}
export default datum;