diff options
author | Gael Guennebaud <g.gael@free.fr> | 2008-12-05 15:56:28 +0000 |
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committer | Gael Guennebaud <g.gael@free.fr> | 2008-12-05 15:56:28 +0000 |
commit | faf942a94703208ca740e78b386443afb4505c60 (patch) | |
tree | 17e710ff2f024559f2feb02a44855c473502658c /Eigen/src/Geometry/EulerAngles.h | |
parent | 6d1439a52fb5e66ea6040324d2fd170bea1f8a96 (diff) |
Add a generic matrix to Euler-angles function.
Perhaps the prototype of this function could be improved,
see comments in the code
Diffstat (limited to 'Eigen/src/Geometry/EulerAngles.h')
-rw-r--r-- | Eigen/src/Geometry/EulerAngles.h | 100 |
1 files changed, 100 insertions, 0 deletions
diff --git a/Eigen/src/Geometry/EulerAngles.h b/Eigen/src/Geometry/EulerAngles.h new file mode 100644 index 000000000..6087a1433 --- /dev/null +++ b/Eigen/src/Geometry/EulerAngles.h @@ -0,0 +1,100 @@ +// This file is part of Eigen, a lightweight C++ template library +// for linear algebra. Eigen itself is part of the KDE project. +// +// Copyright (C) 2008 Gael Guennebaud <g.gael@free.fr> +// +// Eigen is free software; you can redistribute it and/or +// modify it under the terms of the GNU Lesser General Public +// License as published by the Free Software Foundation; either +// version 3 of the License, or (at your option) any later version. +// +// Alternatively, you can redistribute it and/or +// modify it under the terms of the GNU General Public License as +// published by the Free Software Foundation; either version 2 of +// the License, or (at your option) any later version. +// +// Eigen is distributed in the hope that it will be useful, but WITHOUT ANY +// WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS +// FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License or the +// GNU General Public License for more details. +// +// You should have received a copy of the GNU Lesser General Public +// License and a copy of the GNU General Public License along with +// Eigen. If not, see <http://www.gnu.org/licenses/>. + +#ifndef EIGEN_EULERANGLES_H +#define EIGEN_EULERANGLES_H + +/** \geometry_module \ingroup GeometryModule + * \nonstableyet + * + * \returns the Euler-angles of the rotation matrix \c *this using the convention defined by the triplet (\a a0,\a a1,\a a2) + * + * Each of the three parameters \a a0,\a a1,\a a2 represents the respective rotation axis as an integer in {0,1,2}. + * For instance, in: + * \code Vector3f ea = mat.eulerAngles(2, 0, 2); \endcode + * "2" represents the z axis and "0" the x axis, etc. The returned angles are such that + * we have the following equality: + * \code + * mat == AngleAxisf(ea[0], Vector3f::UnitZ()) + * * AngleAxisf(ea[1], Vector3f::UnitX()) + * * AngleAxisf(ea[2], Vector3f::UnitZ()); \endcode + * This corresponds to the right-multiply conventions (with right hand side frames). + */ +// FIXME perhaps the triplet could be template parameters +// and/or packed into constants: EulerXYZ, EulerXYX, etc.... +// FIXME should we support the reversed conventions ? (left multiply) +template<typename Derived> +inline Matrix<typename MatrixBase<Derived>::Scalar,3,1> +MatrixBase<Derived>::eulerAngles(int a0, int a1, int a2) const +{ + EIGEN_STATIC_ASSERT_MATRIX_SPECIFIC_SIZE(Derived,3,3) + + Matrix<Scalar,3,1> res; + typedef Matrix<typename Derived::Scalar,2,1> Vector2; + const Scalar epsilon = precision<Scalar>(); + + const int odd = ((a0+1)%3 == a1) ? 0 : 1; + const int i = a0; + const int j = (a0 + 1 + odd)%3; + const int k = (a0 + 2 - odd)%3; + + if (a0==a2) + { + Scalar s = Vector2(coeff(j,i) , coeff(k,i)).norm(); + + res[1] = std::atan2(s, coeff(i,i)); + if (s > epsilon) + { + res[0] = std::atan2(coeff(j,i), coeff(k,i)); + res[2] = std::atan2(coeff(i,j),-coeff(i,k)); + } + else + { + res[0] = Scalar(0); + res[2] = std::atan2(-coeff(k,j), coeff(j,j)); + } + } + else + { + Scalar c = Vector2(coeff(i,i) , coeff(i,j)).norm(); + + res[1] = std::atan2(-coeff(i,k), c); + if (c > epsilon) + { + res[0] = std::atan2(coeff(j,k), coeff(k,k)); + res[2] = std::atan2(coeff(i,j), coeff(i,i)); + } + else + { + res[0] = Scalar(0); + res[2] = -std::atan2(-coeff(k,j), coeff(j,j)); + } + } + if (!odd) + res = -res; + return res; +} + + +#endif // EIGEN_EULERANGLES_H |