1   /* Copyright 2002-2025 CS GROUP
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.forces.gravity.potential;
18  
19  
20  /** Enumerate for tie systems.
21   * <p>
22   * Tide-systems are used to identify if the permanent tide is already present in
23   * the gravity field or if it should be handled when computing the solid tides
24   * force model.
25   * </p>
26   * @see SphericalHarmonicsProvider
27   * @author Luc Maisonobe
28   * @since 6.0
29   */
30  public enum TideSystem {
31  
32      /** Constant for tide-free gravity fields.
33       * <p>
34       * Tide-free fields don't include the permanent tide,
35       * so it must be taken care of when computing the solid tides effects.
36       * </p>
37       */
38      TIDE_FREE,
39  
40      /** Constant for zero-tide gravity fields.
41       * <p>
42       * Zero-tide systems already include the permanent tide,
43       * so the solid tides effects must not add them, to avoid it been counted twice.
44       * </p>
45       */
46      ZERO_TIDE,
47  
48      /** Constant for unknown tide system.
49       */
50      UNKNOWN;
51  
52  }