1 /*
2  * Copyright (C) 2021 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 #pragma once
17 
18 #include <Eigen/Geometry>
19 
20 namespace android {
21 namespace media {
22 
23 /**
24  * Converts a rotation vector to an equivalent quaternion.
25  * The rotation vector is given as a 3-vector whose direction represents the rotation axis and its
26  * magnitude the rotation angle (in radians) around that axis.
27  */
28 Eigen::Quaternionf rotationVectorToQuaternion(const Eigen::Vector3f& rotationVector);
29 
30 /**
31  * Converts a quaternion to an equivalent rotation vector.
32  * The rotation vector is given as a 3-vector whose direction represents the rotation axis and its
33  * magnitude the rotation angle (in radians) around that axis.
34  */
35 Eigen::Vector3f quaternionToRotationVector(const Eigen::Quaternionf& quaternion);
36 
37 /**
38  * Returns a quaternion representing a rotation around the X-axis with the given amount (in
39  * radians).
40  */
41 Eigen::Quaternionf rotateX(float angle);
42 
43 /**
44  * Returns a quaternion representing a rotation around the Y-axis with the given amount (in
45  * radians).
46  */
47 Eigen::Quaternionf rotateY(float angle);
48 
49 /**
50  * Returns a quaternion representing a rotation around the Z-axis with the given amount (in
51  * radians).
52  */
53 Eigen::Quaternionf rotateZ(float angle);
54 
55 }  // namespace media
56 }  // namespace android
57