| /* |
| * Licensed to the Apache Software Foundation (ASF) under one or more |
| * contributor license agreements. See the NOTICE file distributed with |
| * this work for additional information regarding copyright ownership. |
| * The ASF licenses this file to You under the Apache License, Version 2.0 |
| * (the "License"); you may not use this file except in compliance with |
| * the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| package org.apache.commons.geometry.euclidean.threed.rotation; |
| |
| /** Enum defining the possible reference frames for locating axis |
| * positions during a rotation sequence. |
| */ |
| public enum AxisReferenceFrame { |
| |
| /** Defines a relative reference frame for a rotation sequence. Sequences |
| * with this type of reference frame are called <em>intrinsic rotations</em>. |
| * |
| * <p> |
| * When using a relative reference frame, each successive axis |
| * is located relative to the "thing" being rotated and not to some |
| * external frame of reference. For example, say that a rotation sequence |
| * is defined around the {@code x}, {@code y}, and {@code z} axes in |
| * that order. The first rotation will occur around the standard {@code x} |
| * axis. The second rotation, however, will occur around the {@code y} |
| * axis after it has been rotated by the first rotation; we can call this |
| * new axis {@code y'}. Similarly, the third rotation will occur around |
| * {@code z''}, which may or may not match the original {@code z} axis. |
| * A good real-world example of this type of situation is an airplane, |
| * where a pilot makes a sequence of rotations in order, with each rotation |
| * using the airplane's own up/down, left/right, back/forward directions |
| * as the frame of reference. |
| * </p> |
| */ |
| RELATIVE, |
| |
| /** Defines an absolute reference frame for a rotation sequence. Sequences |
| * with this type of reference frame are called <em>extrinsic rotations</em>. |
| * |
| * <p> |
| * In contrast with the relative reference frame, the absolute reference frame |
| * remains fixed throughout a rotation sequence, with each rotation axis not |
| * affected by the rotations. |
| * </p> |
| */ |
| ABSOLUTE |
| } |