1   /* Contributed in the public domain.
2    * Licensed to CS GROUP (CS) under one or more
3    * contributor license agreements.  See the NOTICE file distributed with
4    * this work for additional information regarding copyright ownership.
5    * CS licenses this file to You under the Apache License, Version 2.0
6    * (the "License"); you may not use this file except in compliance with
7    * the License.  You may obtain a copy of the License at
8    *
9    *   http://www.apache.org/licenses/LICENSE-2.0
10   *
11   * Unless required by applicable law or agreed to in writing, software
12   * distributed under the License is distributed on an "AS IS" BASIS,
13   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14   * See the License for the specific language governing permissions and
15   * limitations under the License.
16   */
17  package org.orekit.models.earth;
18  
19  import org.orekit.bodies.BodyShape;
20  
21  /**
22   * All models of Earth's shape have some common properties that are not shared with
23   * arbitrary {@link BodyShape}s. In particular, an ellipsoidal (or spherical) model is
24   * used to compute latitude and longitude.
25   *
26   * @author Evan Ward
27   * @see #getEllipsoid()
28   */
29  public interface EarthShape extends BodyShape {
30  
31      /**
32       * Get the underlying ellipsoid model that defines latitude and longitude. If the
33       * height component of a {@link org.orekit.bodies.GeodeticPoint} is not needed,
34       * then using the ellipsoid will provide the quickest transformation.
35       *
36       * @return the reference ellipsoid. May be {@code this}, but never {@code null}.
37       */
38      ReferenceEllipsoid getEllipsoid();
39  
40  }