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Diffstat (limited to 'eigen/Eigen/src/Geometry/AngleAxis.h')
-rw-r--r-- | eigen/Eigen/src/Geometry/AngleAxis.h | 240 |
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diff --git a/eigen/Eigen/src/Geometry/AngleAxis.h b/eigen/Eigen/src/Geometry/AngleAxis.h new file mode 100644 index 0000000..a8d3cdc --- /dev/null +++ b/eigen/Eigen/src/Geometry/AngleAxis.h @@ -0,0 +1,240 @@ +// This file is part of Eigen, a lightweight C++ template library +// for linear algebra. +// +// Copyright (C) 2008 Gael Guennebaud <gael.guennebaud@inria.fr> +// +// This Source Code Form is subject to the terms of the Mozilla +// Public License v. 2.0. If a copy of the MPL was not distributed +// with this file, You can obtain one at http://mozilla.org/MPL/2.0/. + +#ifndef EIGEN_ANGLEAXIS_H +#define EIGEN_ANGLEAXIS_H + +namespace Eigen { + +/** \geometry_module \ingroup Geometry_Module + * + * \class AngleAxis + * + * \brief Represents a 3D rotation as a rotation angle around an arbitrary 3D axis + * + * \param _Scalar the scalar type, i.e., the type of the coefficients. + * + * \warning When setting up an AngleAxis object, the axis vector \b must \b be \b normalized. + * + * The following two typedefs are provided for convenience: + * \li \c AngleAxisf for \c float + * \li \c AngleAxisd for \c double + * + * Combined with MatrixBase::Unit{X,Y,Z}, AngleAxis can be used to easily + * mimic Euler-angles. Here is an example: + * \include AngleAxis_mimic_euler.cpp + * Output: \verbinclude AngleAxis_mimic_euler.out + * + * \note This class is not aimed to be used to store a rotation transformation, + * but rather to make easier the creation of other rotation (Quaternion, rotation Matrix) + * and transformation objects. + * + * \sa class Quaternion, class Transform, MatrixBase::UnitX() + */ + +namespace internal { +template<typename _Scalar> struct traits<AngleAxis<_Scalar> > +{ + typedef _Scalar Scalar; +}; +} + +template<typename _Scalar> +class AngleAxis : public RotationBase<AngleAxis<_Scalar>,3> +{ + typedef RotationBase<AngleAxis<_Scalar>,3> Base; + +public: + + using Base::operator*; + + enum { Dim = 3 }; + /** the scalar type of the coefficients */ + typedef _Scalar Scalar; + typedef Matrix<Scalar,3,3> Matrix3; + typedef Matrix<Scalar,3,1> Vector3; + typedef Quaternion<Scalar> QuaternionType; + +protected: + + Vector3 m_axis; + Scalar m_angle; + +public: + + /** Default constructor without initialization. */ + AngleAxis() {} + /** Constructs and initialize the angle-axis rotation from an \a angle in radian + * and an \a axis which \b must \b be \b normalized. + * + * \warning If the \a axis vector is not normalized, then the angle-axis object + * represents an invalid rotation. */ + template<typename Derived> + inline AngleAxis(const Scalar& angle, const MatrixBase<Derived>& axis) : m_axis(axis), m_angle(angle) {} + /** Constructs and initialize the angle-axis rotation from a quaternion \a q. */ + template<typename QuatDerived> inline explicit AngleAxis(const QuaternionBase<QuatDerived>& q) { *this = q; } + /** Constructs and initialize the angle-axis rotation from a 3x3 rotation matrix. */ + template<typename Derived> + inline explicit AngleAxis(const MatrixBase<Derived>& m) { *this = m; } + + /** \returns the value of the rotation angle in radian */ + Scalar angle() const { return m_angle; } + /** \returns a read-write reference to the stored angle in radian */ + Scalar& angle() { return m_angle; } + + /** \returns the rotation axis */ + const Vector3& axis() const { return m_axis; } + /** \returns a read-write reference to the stored rotation axis. + * + * \warning The rotation axis must remain a \b unit vector. + */ + Vector3& axis() { return m_axis; } + + /** Concatenates two rotations */ + inline QuaternionType operator* (const AngleAxis& other) const + { return QuaternionType(*this) * QuaternionType(other); } + + /** Concatenates two rotations */ + inline QuaternionType operator* (const QuaternionType& other) const + { return QuaternionType(*this) * other; } + + /** Concatenates two rotations */ + friend inline QuaternionType operator* (const QuaternionType& a, const AngleAxis& b) + { return a * QuaternionType(b); } + + /** \returns the inverse rotation, i.e., an angle-axis with opposite rotation angle */ + AngleAxis inverse() const + { return AngleAxis(-m_angle, m_axis); } + + template<class QuatDerived> + AngleAxis& operator=(const QuaternionBase<QuatDerived>& q); + template<typename Derived> + AngleAxis& operator=(const MatrixBase<Derived>& m); + + template<typename Derived> + AngleAxis& fromRotationMatrix(const MatrixBase<Derived>& m); + Matrix3 toRotationMatrix(void) const; + + /** \returns \c *this with scalar type casted to \a NewScalarType + * + * Note that if \a NewScalarType is equal to the current scalar type of \c *this + * then this function smartly returns a const reference to \c *this. + */ + template<typename NewScalarType> + inline typename internal::cast_return_type<AngleAxis,AngleAxis<NewScalarType> >::type cast() const + { return typename internal::cast_return_type<AngleAxis,AngleAxis<NewScalarType> >::type(*this); } + + /** Copy constructor with scalar type conversion */ + template<typename OtherScalarType> + inline explicit AngleAxis(const AngleAxis<OtherScalarType>& other) + { + m_axis = other.axis().template cast<Scalar>(); + m_angle = Scalar(other.angle()); + } + + static inline const AngleAxis Identity() { return AngleAxis(Scalar(0), Vector3::UnitX()); } + + /** \returns \c true if \c *this is approximately equal to \a other, within the precision + * determined by \a prec. + * + * \sa MatrixBase::isApprox() */ + bool isApprox(const AngleAxis& other, const typename NumTraits<Scalar>::Real& prec = NumTraits<Scalar>::dummy_precision()) const + { return m_axis.isApprox(other.m_axis, prec) && internal::isApprox(m_angle,other.m_angle, prec); } +}; + +/** \ingroup Geometry_Module + * single precision angle-axis type */ +typedef AngleAxis<float> AngleAxisf; +/** \ingroup Geometry_Module + * double precision angle-axis type */ +typedef AngleAxis<double> AngleAxisd; + +/** Set \c *this from a \b unit quaternion. + * The axis is normalized. + * + * \warning As any other method dealing with quaternion, if the input quaternion + * is not normalized then the result is undefined. + */ +template<typename Scalar> +template<typename QuatDerived> +AngleAxis<Scalar>& AngleAxis<Scalar>::operator=(const QuaternionBase<QuatDerived>& q) +{ + using std::acos; + using std::min; + using std::max; + using std::sqrt; + Scalar n2 = q.vec().squaredNorm(); + if (n2 < NumTraits<Scalar>::dummy_precision()*NumTraits<Scalar>::dummy_precision()) + { + m_angle = Scalar(0); + m_axis << Scalar(1), Scalar(0), Scalar(0); + } + else + { + m_angle = Scalar(2)*acos((min)((max)(Scalar(-1),q.w()),Scalar(1))); + m_axis = q.vec() / sqrt(n2); + } + return *this; +} + +/** Set \c *this from a 3x3 rotation matrix \a mat. + */ +template<typename Scalar> +template<typename Derived> +AngleAxis<Scalar>& AngleAxis<Scalar>::operator=(const MatrixBase<Derived>& mat) +{ + // Since a direct conversion would not be really faster, + // let's use the robust Quaternion implementation: + return *this = QuaternionType(mat); +} + +/** +* \brief Sets \c *this from a 3x3 rotation matrix. +**/ +template<typename Scalar> +template<typename Derived> +AngleAxis<Scalar>& AngleAxis<Scalar>::fromRotationMatrix(const MatrixBase<Derived>& mat) +{ + return *this = QuaternionType(mat); +} + +/** Constructs and \returns an equivalent 3x3 rotation matrix. + */ +template<typename Scalar> +typename AngleAxis<Scalar>::Matrix3 +AngleAxis<Scalar>::toRotationMatrix(void) const +{ + using std::sin; + using std::cos; + Matrix3 res; + Vector3 sin_axis = sin(m_angle) * m_axis; + Scalar c = cos(m_angle); + Vector3 cos1_axis = (Scalar(1)-c) * m_axis; + + Scalar tmp; + tmp = cos1_axis.x() * m_axis.y(); + res.coeffRef(0,1) = tmp - sin_axis.z(); + res.coeffRef(1,0) = tmp + sin_axis.z(); + + tmp = cos1_axis.x() * m_axis.z(); + res.coeffRef(0,2) = tmp + sin_axis.y(); + res.coeffRef(2,0) = tmp - sin_axis.y(); + + tmp = cos1_axis.y() * m_axis.z(); + res.coeffRef(1,2) = tmp - sin_axis.x(); + res.coeffRef(2,1) = tmp + sin_axis.x(); + + res.diagonal() = (cos1_axis.cwiseProduct(m_axis)).array() + c; + + return res; +} + +} // end namespace Eigen + +#endif // EIGEN_ANGLEAXIS_H |