1/*
2 * Licensed to the Apache Software Foundation (ASF) under one or more
3 * contributor license agreements.  See the NOTICE file distributed with
4 * this work for additional information regarding copyright ownership.
5 * The ASF 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
18package org.apache.commons.math.geometry;
19
20/**
21 * This class is a utility representing a rotation order specification
22 * for Cardan or Euler angles specification.
23 *
24 * This class cannot be instanciated by the user. He can only use one
25 * of the twelve predefined supported orders as an argument to either
26 * the {@link Rotation#Rotation(RotationOrder,double,double,double)}
27 * constructor or the {@link Rotation#getAngles} method.
28 *
29 * @version $Revision: 811827 $ $Date: 2009-09-06 17:32:50 +0200 (dim. 06 sept. 2009) $
30 * @since 1.2
31 */
32public final class RotationOrder {
33
34    /** Set of Cardan angles.
35     * this ordered set of rotations is around X, then around Y, then
36     * around Z
37     */
38    public static final RotationOrder XYZ =
39      new RotationOrder("XYZ", Vector3D.PLUS_I, Vector3D.PLUS_J, Vector3D.PLUS_K);
40
41    /** Set of Cardan angles.
42     * this ordered set of rotations is around X, then around Z, then
43     * around Y
44     */
45    public static final RotationOrder XZY =
46      new RotationOrder("XZY", Vector3D.PLUS_I, Vector3D.PLUS_K, Vector3D.PLUS_J);
47
48    /** Set of Cardan angles.
49     * this ordered set of rotations is around Y, then around X, then
50     * around Z
51     */
52    public static final RotationOrder YXZ =
53      new RotationOrder("YXZ", Vector3D.PLUS_J, Vector3D.PLUS_I, Vector3D.PLUS_K);
54
55    /** Set of Cardan angles.
56     * this ordered set of rotations is around Y, then around Z, then
57     * around X
58     */
59    public static final RotationOrder YZX =
60      new RotationOrder("YZX", Vector3D.PLUS_J, Vector3D.PLUS_K, Vector3D.PLUS_I);
61
62    /** Set of Cardan angles.
63     * this ordered set of rotations is around Z, then around X, then
64     * around Y
65     */
66    public static final RotationOrder ZXY =
67      new RotationOrder("ZXY", Vector3D.PLUS_K, Vector3D.PLUS_I, Vector3D.PLUS_J);
68
69    /** Set of Cardan angles.
70     * this ordered set of rotations is around Z, then around Y, then
71     * around X
72     */
73    public static final RotationOrder ZYX =
74      new RotationOrder("ZYX", Vector3D.PLUS_K, Vector3D.PLUS_J, Vector3D.PLUS_I);
75
76    /** Set of Euler angles.
77     * this ordered set of rotations is around X, then around Y, then
78     * around X
79     */
80    public static final RotationOrder XYX =
81      new RotationOrder("XYX", Vector3D.PLUS_I, Vector3D.PLUS_J, Vector3D.PLUS_I);
82
83    /** Set of Euler angles.
84     * this ordered set of rotations is around X, then around Z, then
85     * around X
86     */
87    public static final RotationOrder XZX =
88      new RotationOrder("XZX", Vector3D.PLUS_I, Vector3D.PLUS_K, Vector3D.PLUS_I);
89
90    /** Set of Euler angles.
91     * this ordered set of rotations is around Y, then around X, then
92     * around Y
93     */
94    public static final RotationOrder YXY =
95      new RotationOrder("YXY", Vector3D.PLUS_J, Vector3D.PLUS_I, Vector3D.PLUS_J);
96
97    /** Set of Euler angles.
98     * this ordered set of rotations is around Y, then around Z, then
99     * around Y
100     */
101    public static final RotationOrder YZY =
102      new RotationOrder("YZY", Vector3D.PLUS_J, Vector3D.PLUS_K, Vector3D.PLUS_J);
103
104    /** Set of Euler angles.
105     * this ordered set of rotations is around Z, then around X, then
106     * around Z
107     */
108    public static final RotationOrder ZXZ =
109      new RotationOrder("ZXZ", Vector3D.PLUS_K, Vector3D.PLUS_I, Vector3D.PLUS_K);
110
111    /** Set of Euler angles.
112     * this ordered set of rotations is around Z, then around Y, then
113     * around Z
114     */
115    public static final RotationOrder ZYZ =
116      new RotationOrder("ZYZ", Vector3D.PLUS_K, Vector3D.PLUS_J, Vector3D.PLUS_K);
117
118    /** Name of the rotations order. */
119    private final String name;
120
121    /** Axis of the first rotation. */
122    private final Vector3D a1;
123
124    /** Axis of the second rotation. */
125    private final Vector3D a2;
126
127    /** Axis of the third rotation. */
128    private final Vector3D a3;
129
130    /** Private constructor.
131     * This is a utility class that cannot be instantiated by the user,
132     * so its only constructor is private.
133     * @param name name of the rotation order
134     * @param a1 axis of the first rotation
135     * @param a2 axis of the second rotation
136     * @param a3 axis of the third rotation
137     */
138    private RotationOrder(final String name,
139                          final Vector3D a1, final Vector3D a2, final Vector3D a3) {
140        this.name = name;
141        this.a1   = a1;
142        this.a2   = a2;
143        this.a3   = a3;
144    }
145
146    /** Get a string representation of the instance.
147     * @return a string representation of the instance (in fact, its name)
148     */
149    @Override
150    public String toString() {
151        return name;
152    }
153
154    /** Get the axis of the first rotation.
155     * @return axis of the first rotation
156     */
157    public Vector3D getA1() {
158        return a1;
159    }
160
161    /** Get the axis of the second rotation.
162     * @return axis of the second rotation
163     */
164    public Vector3D getA2() {
165        return a2;
166    }
167
168    /** Get the axis of the second rotation.
169     * @return axis of the second rotation
170     */
171    public Vector3D getA3() {
172        return a3;
173    }
174
175}
176