001    /*
002     * Licensed to the Apache Software Foundation (ASF) under one or more
003     * contributor license agreements.  See the NOTICE file distributed with
004     * this work for additional information regarding copyright ownership.
005     * The ASF licenses this file to You under the Apache License, Version 2.0
006     * (the "License"); you may not use this file except in compliance with
007     * the License.  You may obtain a copy of the License at
008     *
009     *      http://www.apache.org/licenses/LICENSE-2.0
010     *
011     * Unless required by applicable law or agreed to in writing, software
012     * distributed under the License is distributed on an "AS IS" BASIS,
013     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014     * See the License for the specific language governing permissions and
015     * limitations under the License.
016     */
017    
018    package org.apache.commons.math3.geometry.euclidean.threed;
019    
020    /**
021     * This class is a utility representing a rotation order specification
022     * for Cardan or Euler angles specification.
023     *
024     * This class cannot be instanciated by the user. He can only use one
025     * of the twelve predefined supported orders as an argument to either
026     * the {@link Rotation#Rotation(RotationOrder,double,double,double)}
027     * constructor or the {@link Rotation#getAngles} method.
028     *
029     * @version $Id: RotationOrder.java 1416643 2012-12-03 19:37:14Z tn $
030     * @since 1.2
031     */
032    public final class RotationOrder {
033    
034        /** Set of Cardan angles.
035         * this ordered set of rotations is around X, then around Y, then
036         * around Z
037         */
038        public static final RotationOrder XYZ =
039          new RotationOrder("XYZ", Vector3D.PLUS_I, Vector3D.PLUS_J, Vector3D.PLUS_K);
040    
041        /** Set of Cardan angles.
042         * this ordered set of rotations is around X, then around Z, then
043         * around Y
044         */
045        public static final RotationOrder XZY =
046          new RotationOrder("XZY", Vector3D.PLUS_I, Vector3D.PLUS_K, Vector3D.PLUS_J);
047    
048        /** Set of Cardan angles.
049         * this ordered set of rotations is around Y, then around X, then
050         * around Z
051         */
052        public static final RotationOrder YXZ =
053          new RotationOrder("YXZ", Vector3D.PLUS_J, Vector3D.PLUS_I, Vector3D.PLUS_K);
054    
055        /** Set of Cardan angles.
056         * this ordered set of rotations is around Y, then around Z, then
057         * around X
058         */
059        public static final RotationOrder YZX =
060          new RotationOrder("YZX", Vector3D.PLUS_J, Vector3D.PLUS_K, Vector3D.PLUS_I);
061    
062        /** Set of Cardan angles.
063         * this ordered set of rotations is around Z, then around X, then
064         * around Y
065         */
066        public static final RotationOrder ZXY =
067          new RotationOrder("ZXY", Vector3D.PLUS_K, Vector3D.PLUS_I, Vector3D.PLUS_J);
068    
069        /** Set of Cardan angles.
070         * this ordered set of rotations is around Z, then around Y, then
071         * around X
072         */
073        public static final RotationOrder ZYX =
074          new RotationOrder("ZYX", Vector3D.PLUS_K, Vector3D.PLUS_J, Vector3D.PLUS_I);
075    
076        /** Set of Euler angles.
077         * this ordered set of rotations is around X, then around Y, then
078         * around X
079         */
080        public static final RotationOrder XYX =
081          new RotationOrder("XYX", Vector3D.PLUS_I, Vector3D.PLUS_J, Vector3D.PLUS_I);
082    
083        /** Set of Euler angles.
084         * this ordered set of rotations is around X, then around Z, then
085         * around X
086         */
087        public static final RotationOrder XZX =
088          new RotationOrder("XZX", Vector3D.PLUS_I, Vector3D.PLUS_K, Vector3D.PLUS_I);
089    
090        /** Set of Euler angles.
091         * this ordered set of rotations is around Y, then around X, then
092         * around Y
093         */
094        public static final RotationOrder YXY =
095          new RotationOrder("YXY", Vector3D.PLUS_J, Vector3D.PLUS_I, Vector3D.PLUS_J);
096    
097        /** Set of Euler angles.
098         * this ordered set of rotations is around Y, then around Z, then
099         * 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    }