001/*
002 *    GeoAPI - Java interfaces for OGC/ISO standards
003 *    Copyright © 2003-2023 Open Geospatial Consortium, Inc.
004 *    http://www.geoapi.org
005 *
006 *    Licensed under the Apache License, Version 2.0 (the "License");
007 *    you may not use this file except in compliance with the License.
008 *    You may obtain a copy of the License at
009 *
010 *        http://www.apache.org/licenses/LICENSE-2.0
011 *
012 *    Unless required by applicable law or agreed to in writing, software
013 *    distributed under the License is distributed on an "AS IS" BASIS,
014 *    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
015 *    See the License for the specific language governing permissions and
016 *    limitations under the License.
017 */
018package org.opengis.referencing.crs;
019
020import java.util.Map;
021import org.opengis.referencing.cs.CoordinateSystem;
022import org.opengis.referencing.datum.DatumEnsemble;
023import org.opengis.referencing.datum.EngineeringDatum;
024import org.opengis.annotation.UML;
025
026import static org.opengis.annotation.Obligation.*;
027import static org.opengis.annotation.Specification.*;
028
029
030/**
031 * A 1-, 2- or 3-dimensional <abbr>CRS</abbr> used locally.
032 * It can be divided into three broad categories:
033 *
034 * <ul>
035 *   <li>planet-fixed systems applied to engineering activities on or near the surface of the planet;</li>
036 *   <li><abbr>CRS</abbr>s on moving platforms such as road vehicles, vessels, aircraft, or spacecraft.</li>
037 *   <li><abbr>CRS</abbr>s used to describe spatial location internally on an image.</li>
038 * </ul>
039 *
040 * <p>Planet-fixed engineering <abbr>CRS</abbr>s are commonly based on a simple flat-earth approximation
041 * of the planet's surface, and the effect of planet curvature on feature geometry is ignored:
042 * calculations on coordinates use simple plane arithmetic without any corrections for planet curvature.</p>
043 *
044 * <p>Engineering <abbr>CRS</abbr>s used on moving platforms
045 * are subject to all the motions of the platform with which they are associated.
046 * In this case the associated coordinates are meaningful only relative to the moving platform.
047 * Transformation of coordinates from these moving engineering <abbr>CRS</abbr>s to planet-referenced
048 * <abbr>CRS</abbr>s involves time-dependent coordinate operation parameters.</p>
049 *
050 * <h2>Permitted coordinate systems</h2>
051 * This type of CRS can be used with coordinate systems of type
052 * {@link org.opengis.referencing.cs.AffineCS},
053 * {@link org.opengis.referencing.cs.CartesianCS},
054 * {@link org.opengis.referencing.cs.CylindricalCS},
055 * {@link org.opengis.referencing.cs.LinearCS},
056 * {@link org.opengis.referencing.cs.PolarCS},
057 * {@link org.opengis.referencing.cs.SphericalCS}.
058 *
059 * @author  OGC Topic 2 (for abstract model and documentation)
060 * @author  Martin Desruisseaux (IRD, Geomatys)
061 * @version 3.1
062 * @since   1.0
063 *
064 * @see CRSAuthorityFactory#createEngineeringCRS(String)
065 * @see CRSFactory#createEngineeringCRS(Map, EngineeringDatum, DatumEnsemble, CoordinateSystem)
066 */
067@UML(identifier="EngineeringCRS", specification=ISO_19111)
068public interface EngineeringCRS extends SingleCRS {
069    /**
070     * Returns the datum, which shall be an engineering one.
071     * This property may be null if this <abbr>CRS</abbr> is related to an object
072     * identified only by a {@linkplain #getDatumEnsemble() datum ensemble}.
073     *
074     * @return the engineering datum, or {@code null} if this <abbr>CRS</abbr> is related to
075     *         an object identified only by a {@linkplain #getDatumEnsemble() datum ensemble}.
076     *
077     * @condition Mandatory if the {@linkplain #getDatumEnsemble() datum ensemble} is not documented.
078     */
079    @Override
080    @UML(identifier="datum", obligation=CONDITIONAL, specification=ISO_19111)
081    EngineeringDatum getDatum();
082
083    /**
084     * Returns the datum ensemble, which shall have engineering datum members.
085     * This property may be null if this <abbr>CRS</abbr> is related to an object
086     * identified only by a single {@linkplain #getDatum() datum}.
087     *
088     * <p>The default implementation returns {@code null}.</p>
089     *
090     * @return the datum ensemble, or {@code null} if this <abbr>CRS</abbr> is related
091     *         to an object identified only by a single {@linkplain #getDatum() datum}.
092     *
093     * @condition Mandatory if the {@linkplain #getDatum() datum} is not documented.
094     * @since 3.1
095     */
096    @Override
097    @UML(identifier="datum", obligation=CONDITIONAL, specification=ISO_19111)
098    default DatumEnsemble<EngineeringDatum> getDatumEnsemble() {
099        return null;
100    }
101}