Rotation2D.h
1 // This file is part of Eigen, a lightweight C++ template library
2 // for linear algebra.
3 //
4 // Copyright (C) 2008 Gael Guennebaud <gael.guennebaud@inria.fr>
5 //
6 // This Source Code Form is subject to the terms of the Mozilla
7 // Public License v. 2.0. If a copy of the MPL was not distributed
8 // with this file, You can obtain one at http://mozilla.org/MPL/2.0/.
9 
10 #ifndef EIGEN_ROTATION2D_H
11 #define EIGEN_ROTATION2D_H
12 
13 namespace Eigen {
14 
32 namespace internal {
33 
34 template<typename _Scalar> struct traits<Rotation2D<_Scalar> >
35 {
36  typedef _Scalar Scalar;
37 };
38 } // end namespace internal
39 
40 template<typename _Scalar>
41 class Rotation2D : public RotationBase<Rotation2D<_Scalar>,2>
42 {
43  typedef RotationBase<Rotation2D<_Scalar>,2> Base;
44 
45 public:
46 
47  using Base::operator*;
48 
49  enum { Dim = 2 };
51  typedef _Scalar Scalar;
54 
55 protected:
56 
57  Scalar m_angle;
58 
59 public:
60 
62  inline Rotation2D(Scalar a) : m_angle(a) {}
63 
65  inline Scalar angle() const { return m_angle; }
66 
68  inline Scalar& angle() { return m_angle; }
69 
71  inline Rotation2D inverse() const { return -m_angle; }
72 
74  inline Rotation2D operator*(const Rotation2D& other) const
75  { return m_angle + other.m_angle; }
76 
78  inline Rotation2D& operator*=(const Rotation2D& other)
79  { m_angle += other.m_angle; return *this; }
80 
82  Vector2 operator* (const Vector2& vec) const
83  { return toRotationMatrix() * vec; }
84 
85  template<typename Derived>
86  Rotation2D& fromRotationMatrix(const MatrixBase<Derived>& m);
87  Matrix2 toRotationMatrix(void) const;
88 
92  inline Rotation2D slerp(Scalar t, const Rotation2D& other) const
93  { return m_angle * (1-t) + other.angle() * t; }
94 
100  template<typename NewScalarType>
101  inline typename internal::cast_return_type<Rotation2D,Rotation2D<NewScalarType> >::type cast() const
102  { return typename internal::cast_return_type<Rotation2D,Rotation2D<NewScalarType> >::type(*this); }
103 
105  template<typename OtherScalarType>
106  inline explicit Rotation2D(const Rotation2D<OtherScalarType>& other)
107  {
108  m_angle = Scalar(other.angle());
109  }
110 
111  static inline Rotation2D Identity() { return Rotation2D(0); }
112 
118  { return internal::isApprox(m_angle,other.m_angle, prec); }
119 };
120 
127 
132 template<typename Scalar>
133 template<typename Derived>
135 {
136  EIGEN_STATIC_ASSERT(Derived::RowsAtCompileTime==2 && Derived::ColsAtCompileTime==2,YOU_MADE_A_PROGRAMMING_MISTAKE)
137  m_angle = internal::atan2(mat.coeff(1,0), mat.coeff(0,0));
138  return *this;
139 }
140 
143 template<typename Scalar>
146 {
147  Scalar sinA = internal::sin(m_angle);
148  Scalar cosA = internal::cos(m_angle);
149  return (Matrix2() << cosA, -sinA, sinA, cosA).finished();
150 }
151 
152 } // end namespace Eigen
153 
154 #endif // EIGEN_ROTATION2D_H