001// License: GPL. For details, see LICENSE file.
002package org.openstreetmap.josm.data.projection.datum;
003
004import org.openstreetmap.josm.data.coor.LatLon;
005import org.openstreetmap.josm.data.projection.Ellipsoid;
006
007/**
008 * Represents a geodetic datum.
009 *
010 * Basically it provides conversion functions from and to the WGS84 datum.
011 */
012public interface Datum {
013
014    /**
015     * @return a human readable name of this projection
016     */
017    String getName();
018
019    /**
020     * @return the Proj.4 identifier
021     * (as reported by cs2cs -ld)
022     * If no id exists, return null.
023     */
024    String getProj4Id();
025
026    /**
027     * @return the ellipsoid associated with this datum
028     */
029    Ellipsoid getEllipsoid();
030
031    /**
032     * Convert lat/lon from this datum to WGS84 datum.
033     */
034    LatLon toWGS84(LatLon ll);
035
036    /**
037     * Convert lat/lon from WGS84 to this datum.
038     */
039    LatLon fromWGS84(LatLon ll);
040
041}