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Diffstat (limited to 'unsupported/Eigen/src/EulerAngles/EulerSystem.h')
| -rw-r--r-- | unsupported/Eigen/src/EulerAngles/EulerSystem.h | 326 |
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diff --git a/unsupported/Eigen/src/EulerAngles/EulerSystem.h b/unsupported/Eigen/src/EulerAngles/EulerSystem.h new file mode 100644 index 000000000..98f9f647d --- /dev/null +++ b/unsupported/Eigen/src/EulerAngles/EulerSystem.h @@ -0,0 +1,326 @@ +// This file is part of Eigen, a lightweight C++ template library +// for linear algebra. +// +// Copyright (C) 2015 Tal Hadad <tal_hd@hotmail.com> +// +// 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_EULERSYSTEM_H +#define EIGEN_EULERSYSTEM_H + +namespace Eigen +{ + // Forward declerations + template <typename _Scalar, class _System> + class EulerAngles; + + namespace internal + { + // TODO: Check if already exists on the rest API + template <int Num, bool IsPositive = (Num > 0)> + struct Abs + { + enum { value = Num }; + }; + + template <int Num> + struct Abs<Num, false> + { + enum { value = -Num }; + }; + + template <int Axis> + struct IsValidAxis + { + enum { value = Axis != 0 && Abs<Axis>::value <= 3 }; + }; + } + + #define EIGEN_EULER_ANGLES_CLASS_STATIC_ASSERT(COND,MSG) typedef char static_assertion_##MSG[(COND)?1:-1] + + /** \brief Representation of a fixed signed rotation axis for EulerSystem. + * + * \ingroup EulerAngles_Module + * + * Values here represent: + * - The axis of the rotation: X, Y or Z. + * - The sign (i.e. direction of the rotation along the axis): positive(+) or negative(-) + * + * Therefore, this could express all the axes {+X,+Y,+Z,-X,-Y,-Z} + * + * For positive axis, use +EULER_{axis}, and for negative axis use -EULER_{axis}. + */ + enum EulerAxis + { + EULER_X = 1, /*!< the X axis */ + EULER_Y = 2, /*!< the Y axis */ + EULER_Z = 3 /*!< the Z axis */ + }; + + /** \class EulerSystem + * + * \ingroup EulerAngles_Module + * + * \brief Represents a fixed Euler rotation system. + * + * This meta-class goal is to represent the Euler system in compilation time, for EulerAngles. + * + * You can use this class to get two things: + * - Build an Euler system, and then pass it as a template parameter to EulerAngles. + * - Query some compile time data about an Euler system. (e.g. Whether it's tait bryan) + * + * Euler rotation is a set of three rotation on fixed axes. (see \ref EulerAngles) + * This meta-class store constantly those signed axes. (see \ref EulerAxis) + * + * ### Types of Euler systems ### + * + * All and only valid 3 dimension Euler rotation over standard + * signed axes{+X,+Y,+Z,-X,-Y,-Z} are supported: + * - all axes X, Y, Z in each valid order (see below what order is valid) + * - rotation over the axis is supported both over the positive and negative directions. + * - both tait bryan and proper/classic Euler angles (i.e. the opposite). + * + * Since EulerSystem support both positive and negative directions, + * you may call this rotation distinction in other names: + * - _right handed_ or _left handed_ + * - _counterclockwise_ or _clockwise_ + * + * Notice all axed combination are valid, and would trigger a static assertion. + * Same unsigned axes can't be neighbors, e.g. {X,X,Y} is invalid. + * This yield two and only two classes: + * - _tait bryan_ - all unsigned axes are distinct, e.g. {X,Y,Z} + * - _proper/classic Euler angles_ - The first and the third unsigned axes is equal, + * and the second is different, e.g. {X,Y,X} + * + * ### Intrinsic vs extrinsic Euler systems ### + * + * Only intrinsic Euler systems are supported for simplicity. + * If you want to use extrinsic Euler systems, + * just use the equal intrinsic opposite order for axes and angles. + * I.e axes (A,B,C) becomes (C,B,A), and angles (a,b,c) becomes (c,b,a). + * + * ### Convenient user typedefs ### + * + * Convenient typedefs for EulerSystem exist (only for positive axes Euler systems), + * in a form of EulerSystem{A}{B}{C}, e.g. \ref EulerSystemXYZ. + * + * ### Additional reading ### + * + * More information about Euler angles: https://en.wikipedia.org/wiki/Euler_angles + * + * \tparam _AlphaAxis the first fixed EulerAxis + * + * \tparam _AlphaAxis the second fixed EulerAxis + * + * \tparam _AlphaAxis the third fixed EulerAxis + */ + template <int _AlphaAxis, int _BetaAxis, int _GammaAxis> + class EulerSystem + { + public: + // It's defined this way and not as enum, because I think + // that enum is not guerantee to support negative numbers + + /** The first rotation axis */ + static const int AlphaAxis = _AlphaAxis; + + /** The second rotation axis */ + static const int BetaAxis = _BetaAxis; + + /** The third rotation axis */ + static const int GammaAxis = _GammaAxis; + + enum + { + AlphaAxisAbs = internal::Abs<AlphaAxis>::value, /*!< the first rotation axis unsigned */ + BetaAxisAbs = internal::Abs<BetaAxis>::value, /*!< the second rotation axis unsigned */ + GammaAxisAbs = internal::Abs<GammaAxis>::value, /*!< the third rotation axis unsigned */ + + IsAlphaOpposite = (AlphaAxis < 0) ? 1 : 0, /*!< weather alpha axis is negative */ + IsBetaOpposite = (BetaAxis < 0) ? 1 : 0, /*!< weather beta axis is negative */ + IsGammaOpposite = (GammaAxis < 0) ? 1 : 0, /*!< weather gamma axis is negative */ + + IsOdd = ((AlphaAxisAbs)%3 == (BetaAxisAbs - 1)%3) ? 0 : 1, /*!< weather the Euler system is odd */ + IsEven = IsOdd ? 0 : 1, /*!< weather the Euler system is even */ + + IsTaitBryan = ((unsigned)AlphaAxisAbs != (unsigned)GammaAxisAbs) ? 1 : 0 /*!< weather the Euler system is tait bryan */ + }; + + private: + + EIGEN_EULER_ANGLES_CLASS_STATIC_ASSERT(internal::IsValidAxis<AlphaAxis>::value, + ALPHA_AXIS_IS_INVALID); + + EIGEN_EULER_ANGLES_CLASS_STATIC_ASSERT(internal::IsValidAxis<BetaAxis>::value, + BETA_AXIS_IS_INVALID); + + EIGEN_EULER_ANGLES_CLASS_STATIC_ASSERT(internal::IsValidAxis<GammaAxis>::value, + GAMMA_AXIS_IS_INVALID); + + EIGEN_EULER_ANGLES_CLASS_STATIC_ASSERT((unsigned)AlphaAxisAbs != (unsigned)BetaAxisAbs, + ALPHA_AXIS_CANT_BE_EQUAL_TO_BETA_AXIS); + + EIGEN_EULER_ANGLES_CLASS_STATIC_ASSERT((unsigned)BetaAxisAbs != (unsigned)GammaAxisAbs, + BETA_AXIS_CANT_BE_EQUAL_TO_GAMMA_AXIS); + + enum + { + // I, J, K are the pivot indexes permutation for the rotation matrix, that match this Euler system. + // They are used in this class converters. + // They are always different from each other, and their possible values are: 0, 1, or 2. + I = AlphaAxisAbs - 1, + J = (AlphaAxisAbs - 1 + 1 + IsOdd)%3, + K = (AlphaAxisAbs - 1 + 2 - IsOdd)%3 + }; + + // TODO: Get @mat parameter in form that avoids double evaluation. + template <typename Derived> + static void CalcEulerAngles_imp(Matrix<typename MatrixBase<Derived>::Scalar, 3, 1>& res, const MatrixBase<Derived>& mat, internal::true_type /*isTaitBryan*/) + { + using std::atan2; + using std::sin; + using std::cos; + + typedef typename Derived::Scalar Scalar; + typedef Matrix<Scalar,2,1> Vector2; + + res[0] = atan2(mat(J,K), mat(K,K)); + Scalar c2 = Vector2(mat(I,I), mat(I,J)).norm(); + if((IsOdd && res[0]<Scalar(0)) || ((!IsOdd) && res[0]>Scalar(0))) { + if(res[0] > Scalar(0)) { + res[0] -= Scalar(EIGEN_PI); + } + else { + res[0] += Scalar(EIGEN_PI); + } + res[1] = atan2(-mat(I,K), -c2); + } + else + res[1] = atan2(-mat(I,K), c2); + Scalar s1 = sin(res[0]); + Scalar c1 = cos(res[0]); + res[2] = atan2(s1*mat(K,I)-c1*mat(J,I), c1*mat(J,J) - s1 * mat(K,J)); + } + + template <typename Derived> + static void CalcEulerAngles_imp(Matrix<typename MatrixBase<Derived>::Scalar,3,1>& res, const MatrixBase<Derived>& mat, internal::false_type /*isTaitBryan*/) + { + using std::atan2; + using std::sin; + using std::cos; + + typedef typename Derived::Scalar Scalar; + typedef Matrix<Scalar,2,1> Vector2; + + res[0] = atan2(mat(J,I), mat(K,I)); + if((IsOdd && res[0]<Scalar(0)) || ((!IsOdd) && res[0]>Scalar(0))) + { + if(res[0] > Scalar(0)) { + res[0] -= Scalar(EIGEN_PI); + } + else { + res[0] += Scalar(EIGEN_PI); + } + Scalar s2 = Vector2(mat(J,I), mat(K,I)).norm(); + res[1] = -atan2(s2, mat(I,I)); + } + else + { + Scalar s2 = Vector2(mat(J,I), mat(K,I)).norm(); + res[1] = atan2(s2, mat(I,I)); + } + + // With a=(0,1,0), we have i=0; j=1; k=2, and after computing the first two angles, + // we can compute their respective rotation, and apply its inverse to M. Since the result must + // be a rotation around x, we have: + // + // c2 s1.s2 c1.s2 1 0 0 + // 0 c1 -s1 * M = 0 c3 s3 + // -s2 s1.c2 c1.c2 0 -s3 c3 + // + // Thus: m11.c1 - m21.s1 = c3 & m12.c1 - m22.s1 = s3 + + Scalar s1 = sin(res[0]); + Scalar c1 = cos(res[0]); + res[2] = atan2(c1*mat(J,K)-s1*mat(K,K), c1*mat(J,J) - s1 * mat(K,J)); + } + + template<typename Scalar> + static void CalcEulerAngles( + EulerAngles<Scalar, EulerSystem>& res, + const typename EulerAngles<Scalar, EulerSystem>::Matrix3& mat) + { + CalcEulerAngles(res, mat, false, false, false); + } + + template< + bool PositiveRangeAlpha, + bool PositiveRangeBeta, + bool PositiveRangeGamma, + typename Scalar> + static void CalcEulerAngles( + EulerAngles<Scalar, EulerSystem>& res, + const typename EulerAngles<Scalar, EulerSystem>::Matrix3& mat) + { + CalcEulerAngles(res, mat, PositiveRangeAlpha, PositiveRangeBeta, PositiveRangeGamma); + } + + template<typename Scalar> + static void CalcEulerAngles( + EulerAngles<Scalar, EulerSystem>& res, + const typename EulerAngles<Scalar, EulerSystem>::Matrix3& mat, + bool PositiveRangeAlpha, + bool PositiveRangeBeta, + bool PositiveRangeGamma) + { + CalcEulerAngles_imp( + res.angles(), mat, + typename internal::conditional<IsTaitBryan, internal::true_type, internal::false_type>::type()); + + if (IsAlphaOpposite == IsOdd) + res.alpha() = -res.alpha(); + + if (IsBetaOpposite == IsOdd) + res.beta() = -res.beta(); + + if (IsGammaOpposite == IsOdd) + res.gamma() = -res.gamma(); + + // Saturate results to the requested range + if (PositiveRangeAlpha && (res.alpha() < 0)) + res.alpha() += Scalar(2 * EIGEN_PI); + + if (PositiveRangeBeta && (res.beta() < 0)) + res.beta() += Scalar(2 * EIGEN_PI); + + if (PositiveRangeGamma && (res.gamma() < 0)) + res.gamma() += Scalar(2 * EIGEN_PI); + } + + template <typename _Scalar, class _System> + friend class Eigen::EulerAngles; + }; + +#define EIGEN_EULER_SYSTEM_TYPEDEF(A, B, C) \ + /** \ingroup EulerAngles_Module */ \ + typedef EulerSystem<EULER_##A, EULER_##B, EULER_##C> EulerSystem##A##B##C; + + EIGEN_EULER_SYSTEM_TYPEDEF(X,Y,Z) + EIGEN_EULER_SYSTEM_TYPEDEF(X,Y,X) + EIGEN_EULER_SYSTEM_TYPEDEF(X,Z,Y) + EIGEN_EULER_SYSTEM_TYPEDEF(X,Z,X) + + EIGEN_EULER_SYSTEM_TYPEDEF(Y,Z,X) + EIGEN_EULER_SYSTEM_TYPEDEF(Y,Z,Y) + EIGEN_EULER_SYSTEM_TYPEDEF(Y,X,Z) + EIGEN_EULER_SYSTEM_TYPEDEF(Y,X,Y) + + EIGEN_EULER_SYSTEM_TYPEDEF(Z,X,Y) + EIGEN_EULER_SYSTEM_TYPEDEF(Z,X,Z) + EIGEN_EULER_SYSTEM_TYPEDEF(Z,Y,X) + EIGEN_EULER_SYSTEM_TYPEDEF(Z,Y,Z) +} + +#endif // EIGEN_EULERSYSTEM_H |