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Diffstat (limited to 'Eigen/src/Geometry/Cross.h')
-rw-r--r-- | Eigen/src/Geometry/Cross.h | 102 |
1 files changed, 102 insertions, 0 deletions
diff --git a/Eigen/src/Geometry/Cross.h b/Eigen/src/Geometry/Cross.h new file mode 100644 index 000000000..debe43ca4 --- /dev/null +++ b/Eigen/src/Geometry/Cross.h @@ -0,0 +1,102 @@ +// 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_CROSS_H +#define EIGEN_CROSS_H + +/** \class Cross + * + * \brief Expression of the cross product of two vectors + * + * \param Lhs the type of the left-hand side + * \param Rhs the type of the right-hand side + * + * This class represents an expression of the cross product of two 3D vectors. + * It is the return type of MatrixBase::cross(), and most + * of the time this is the only way it is used. + */ +template<typename Lhs, typename Rhs> +struct ei_traits<Cross<Lhs, Rhs> > +{ + typedef typename Lhs::Scalar Scalar; + typedef typename ei_nested<Lhs,2>::type LhsNested; + typedef typename ei_nested<Rhs,2>::type RhsNested; + typedef typename ei_unref<LhsNested>::type _LhsNested; + typedef typename ei_unref<RhsNested>::type _RhsNested; + enum { + RowsAtCompileTime = 3, + ColsAtCompileTime = 1, + MaxRowsAtCompileTime = 3, + MaxColsAtCompileTime = 1, + Flags = ((_RhsNested::Flags | _LhsNested::Flags) & HereditaryBits) + | EvalBeforeAssigningBit, + CoeffReadCost = NumTraits<Scalar>::AddCost + 2 * NumTraits<Scalar>::MulCost + }; +}; + +template<typename Lhs, typename Rhs> class Cross : ei_no_assignment_operator, + public MatrixBase<Cross<Lhs, Rhs> > +{ + public: + + EIGEN_GENERIC_PUBLIC_INTERFACE(Cross) + typedef typename ei_traits<Cross>::LhsNested LhsNested; + typedef typename ei_traits<Cross>::RhsNested RhsNested; + + Cross(const Lhs& lhs, const Rhs& rhs) + : m_lhs(lhs), m_rhs(rhs) + { + assert(lhs.isVector()); + assert(rhs.isVector()); + assert(lhs.size() == 3 && rhs.size() == 3); + } + + private: + + int _rows() const { return 3; } + int _cols() const { return 1; } + + Scalar _coeff(int i, int) const + { + return m_lhs[(i+1)%3]*m_rhs[(i+2)%3] - m_lhs[(i+2)%3]*m_rhs[(i+1)%3]; + } + + protected: + const LhsNested m_lhs; + const RhsNested m_rhs; +}; + +/** \returns an expression of the cross product of \c *this and \a other + * + * \sa class Cross + */ +template<typename Derived> +template<typename OtherDerived> +const Cross<Derived,OtherDerived> +MatrixBase<Derived>::cross(const MatrixBase<OtherDerived>& other) const +{ + return Cross<Derived,OtherDerived>(derived(),other.derived()); +} + +#endif // EIGEN_CROSS_H |