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.cs; 019 020import java.util.Map; 021import org.opengis.annotation.UML; 022import static org.opengis.annotation.Specification.*; 023 024 025/** 026 * A 1-dimensional coordinate system used to record the heights or depths of points. 027 * Such a coordinate system is usually dependent on the planet's gravity field, perhaps 028 * loosely as when atmospheric pressure is the basis for the vertical coordinate system axis. 029 * An exact definition is deliberately not provided as the complexities of the subject fall 030 * outside the scope of the ISO 19111 specification. 031 * 032 * <p>This type of <abbr>CS</abbr> can be used by coordinate reference systems of type 033 * {@link org.opengis.referencing.crs.VerticalCRS}, potentially in combination with 034 * {@link org.opengis.referencing.crs.DerivedCRS}. 035 * The following examples describe some possible axes for vertical CS used with the above-cited CRS:</p> 036 * 037 * <table class="ogc"> 038 * <caption>Example 1: positive values above sea level</caption> 039 * <tr><th>Axis name</th> <th>Abbr.</th> <th>Direction</th> <th>Unit</th></tr> 040 * <tr><td>Gravity-related height</td> <td>H</td> <td>{@link AxisDirection#UP}</td> <td>metre</td></tr> 041 * </table> 042 * 043 * <table class="ogc"> 044 * <caption>Example 2: positive values below sea level</caption> 045 * <tr><th>Axis name</th> <th>Abbr.</th> <th>Direction</th> <th>Unit</th></tr> 046 * <tr><td>Depth</td> <td>D</td> <td>{@link AxisDirection#DOWN}</td> <td>metre</td></tr> 047 * </table> 048 * 049 * @author OGC Topic 2 (for abstract model and documentation) 050 * @author Martin Desruisseaux (IRD, Geomatys) 051 * @version 3.1 052 * @since 1.0 053 * 054 * @see CSAuthorityFactory#createVerticalCS(String) 055 * @see CSFactory#createVerticalCS(Map, CoordinateSystemAxis) 056 */ 057@UML(identifier="VerticalCS", specification=ISO_19111) 058public interface VerticalCS extends CoordinateSystem { 059 /** 060 * Returns the number of dimensions, which is 1 for this type of coordinate system. 061 * 062 * @return always 1. 063 */ 064 @Override 065 default int getDimension() { 066 return 1; 067 } 068}