| /* |
| * 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.math4.geometry.euclidean.threed; |
| |
| import org.apache.commons.geometry.euclidean.threed.Vector3D; |
| |
| /** |
| * This enumerates is used to differentiate the semantics of a rotation. |
| * @see FieldRotation |
| * @since 3.6 |
| */ |
| public enum RotationConvention { |
| |
| /** Constant for rotation that have the semantics of a vector operator. |
| * <p> |
| * According to this convention, the rotation moves vectors with respect |
| * to a fixed reference frame. |
| * </p> |
| * <p> |
| * This means that if we define rotation r is a 90 degrees rotation around |
| * the Z axis, the image of vector {@link Vector3D.Unit#PLUS_X} would be |
| * {@link Vector3D.Unit#PLUS_Y}, the image of vector {@link Vector3D.Unit#PLUS_Y} |
| * would be {@link Vector3D.Unit#MINUS_X}, the image of vector {@link Vector3D.Unit#PLUS_Z} |
| * would be {@link Vector3D.Unit#PLUS_Z}, and the image of vector with coordinates (1, 2, 3) |
| * would be vector (-2, 1, 3). This means that the vector rotates counterclockwise. |
| * </p> |
| * <p> |
| * This convention was the only one supported by Apache Commons Math up to version 3.5. |
| * </p> |
| * <p> |
| * The difference with {@link #FRAME_TRANSFORM} is only the semantics of the sign |
| * of the angle. It is always possible to create or use a rotation using either |
| * convention to really represent a rotation that would have been best created or |
| * used with the other convention, by changing accordingly the sign of the |
| * rotation angle. This is how things were done up to version 3.5. |
| * </p> |
| */ |
| VECTOR_OPERATOR, |
| |
| /** Constant for rotation that have the semantics of a frame conversion. |
| * <p> |
| * According to this convention, the rotation considered vectors to be fixed, |
| * but their coordinates change as they are converted from an initial frame to |
| * a destination frame rotated with respect to the initial frame. |
| * </p> |
| * <p> |
| * This means that if we define rotation r is a 90 degrees rotation around |
| * the Z axis, the image of vector {@link Vector3D.Unit#PLUS_X} would be |
| * {@link Vector3D.Unit#MINUS_Y}, the image of vector {@link Vector3D.Unit#PLUS_Y} |
| * would be {@link Vector3D.Unit#PLUS_X}, the image of vector {@link Vector3D.Unit#PLUS_Z} |
| * would be {@link Vector3D.Unit#PLUS_Z}, and the image of vector with coordinates (1, 2, 3) |
| * would be vector (2, -1, 3). This means that the coordinates of the vector rotates |
| * clockwise, because they are expressed with respect to a destination frame that is rotated |
| * counterclockwise. |
| * </p> |
| * <p> |
| * The difference with {@link #VECTOR_OPERATOR} is only the semantics of the sign |
| * of the angle. It is always possible to create or use a rotation using either |
| * convention to really represent a rotation that would have been best created or |
| * used with the other convention, by changing accordingly the sign of the |
| * rotation angle. This is how things were done up to version 3.5. |
| * </p> |
| */ |
| FRAME_TRANSFORM; |
| |
| } |