/src/Geometry_Eigen/Eigen/src/Core/Reverse.h
http://github.com/Akranar/daguerreo · C Header · 230 lines · 136 code · 34 blank · 60 comment · 20 complexity · d558fa0acdb9d059178b263a5b103ada MD5 · raw file
- // This file is part of Eigen, a lightweight C++ template library
- // for linear algebra.
- //
- // Copyright (C) 2006-2008 Benoit Jacob <jacob.benoit.1@gmail.com>
- // Copyright (C) 2009 Ricard Marxer <email@ricardmarxer.com>
- // Copyright (C) 2009-2010 Gael Guennebaud <gael.guennebaud@inria.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_REVERSE_H
- #define EIGEN_REVERSE_H
- /** \class Reverse
- * \ingroup Core_Module
- *
- * \brief Expression of the reverse of a vector or matrix
- *
- * \param MatrixType the type of the object of which we are taking the reverse
- *
- * This class represents an expression of the reverse of a vector.
- * It is the return type of MatrixBase::reverse() and VectorwiseOp::reverse()
- * and most of the time this is the only way it is used.
- *
- * \sa MatrixBase::reverse(), VectorwiseOp::reverse()
- */
- namespace internal {
- template<typename MatrixType, int Direction>
- struct traits<Reverse<MatrixType, Direction> >
- : traits<MatrixType>
- {
- typedef typename MatrixType::Scalar Scalar;
- typedef typename traits<MatrixType>::StorageKind StorageKind;
- typedef typename traits<MatrixType>::XprKind XprKind;
- typedef typename nested<MatrixType>::type MatrixTypeNested;
- typedef typename remove_reference<MatrixTypeNested>::type _MatrixTypeNested;
- enum {
- RowsAtCompileTime = MatrixType::RowsAtCompileTime,
- ColsAtCompileTime = MatrixType::ColsAtCompileTime,
- MaxRowsAtCompileTime = MatrixType::MaxRowsAtCompileTime,
- MaxColsAtCompileTime = MatrixType::MaxColsAtCompileTime,
- // let's enable LinearAccess only with vectorization because of the product overhead
- LinearAccess = ( (Direction==BothDirections) && (int(_MatrixTypeNested::Flags)&PacketAccessBit) )
- ? LinearAccessBit : 0,
- Flags = int(_MatrixTypeNested::Flags) & (HereditaryBits | LvalueBit | PacketAccessBit | LinearAccess),
- CoeffReadCost = _MatrixTypeNested::CoeffReadCost
- };
- };
- template<typename PacketScalar, bool ReversePacket> struct reverse_packet_cond
- {
- static inline PacketScalar run(const PacketScalar& x) { return preverse(x); }
- };
- template<typename PacketScalar> struct reverse_packet_cond<PacketScalar,false>
- {
- static inline PacketScalar run(const PacketScalar& x) { return x; }
- };
- } // end namespace internal
- template<typename MatrixType, int Direction> class Reverse
- : public internal::dense_xpr_base< Reverse<MatrixType, Direction> >::type
- {
- public:
- typedef typename internal::dense_xpr_base<Reverse>::type Base;
- EIGEN_DENSE_PUBLIC_INTERFACE(Reverse)
- using Base::IsRowMajor;
- // next line is necessary because otherwise const version of operator()
- // is hidden by non-const version defined in this file
- using Base::operator();
- protected:
- enum {
- PacketSize = internal::packet_traits<Scalar>::size,
- IsColMajor = !IsRowMajor,
- ReverseRow = (Direction == Vertical) || (Direction == BothDirections),
- ReverseCol = (Direction == Horizontal) || (Direction == BothDirections),
- OffsetRow = ReverseRow && IsColMajor ? PacketSize : 1,
- OffsetCol = ReverseCol && IsRowMajor ? PacketSize : 1,
- ReversePacket = (Direction == BothDirections)
- || ((Direction == Vertical) && IsColMajor)
- || ((Direction == Horizontal) && IsRowMajor)
- };
- typedef internal::reverse_packet_cond<PacketScalar,ReversePacket> reverse_packet;
- public:
- inline Reverse(const MatrixType& matrix) : m_matrix(matrix) { }
- EIGEN_INHERIT_ASSIGNMENT_OPERATORS(Reverse)
- inline Index rows() const { return m_matrix.rows(); }
- inline Index cols() const { return m_matrix.cols(); }
- inline Index innerStride() const
- {
- return -m_matrix.innerStride();
- }
- inline Scalar& operator()(Index row, Index col)
- {
- eigen_assert(row >= 0 && row < rows() && col >= 0 && col < cols());
- return coeffRef(row, col);
- }
- inline Scalar& coeffRef(Index row, Index col)
- {
- return m_matrix.const_cast_derived().coeffRef(ReverseRow ? m_matrix.rows() - row - 1 : row,
- ReverseCol ? m_matrix.cols() - col - 1 : col);
- }
- inline CoeffReturnType coeff(Index row, Index col) const
- {
- return m_matrix.coeff(ReverseRow ? m_matrix.rows() - row - 1 : row,
- ReverseCol ? m_matrix.cols() - col - 1 : col);
- }
- inline CoeffReturnType coeff(Index index) const
- {
- return m_matrix.coeff(m_matrix.size() - index - 1);
- }
- inline Scalar& coeffRef(Index index)
- {
- return m_matrix.const_cast_derived().coeffRef(m_matrix.size() - index - 1);
- }
- inline Scalar& operator()(Index index)
- {
- eigen_assert(index >= 0 && index < m_matrix.size());
- return coeffRef(index);
- }
- template<int LoadMode>
- inline const PacketScalar packet(Index row, Index col) const
- {
- return reverse_packet::run(m_matrix.template packet<LoadMode>(
- ReverseRow ? m_matrix.rows() - row - OffsetRow : row,
- ReverseCol ? m_matrix.cols() - col - OffsetCol : col));
- }
- template<int LoadMode>
- inline void writePacket(Index row, Index col, const PacketScalar& x)
- {
- m_matrix.const_cast_derived().template writePacket<LoadMode>(
- ReverseRow ? m_matrix.rows() - row - OffsetRow : row,
- ReverseCol ? m_matrix.cols() - col - OffsetCol : col,
- reverse_packet::run(x));
- }
- template<int LoadMode>
- inline const PacketScalar packet(Index index) const
- {
- return internal::preverse(m_matrix.template packet<LoadMode>( m_matrix.size() - index - PacketSize ));
- }
- template<int LoadMode>
- inline void writePacket(Index index, const PacketScalar& x)
- {
- m_matrix.const_cast_derived().template writePacket<LoadMode>(m_matrix.size() - index - PacketSize, internal::preverse(x));
- }
- protected:
- const typename MatrixType::Nested m_matrix;
- };
- /** \returns an expression of the reverse of *this.
- *
- * Example: \include MatrixBase_reverse.cpp
- * Output: \verbinclude MatrixBase_reverse.out
- *
- */
- template<typename Derived>
- inline typename DenseBase<Derived>::ReverseReturnType
- DenseBase<Derived>::reverse()
- {
- return derived();
- }
- /** This is the const version of reverse(). */
- template<typename Derived>
- inline const typename DenseBase<Derived>::ConstReverseReturnType
- DenseBase<Derived>::reverse() const
- {
- return derived();
- }
- /** This is the "in place" version of reverse: it reverses \c *this.
- *
- * In most cases it is probably better to simply use the reversed expression
- * of a matrix. However, when reversing the matrix data itself is really needed,
- * then this "in-place" version is probably the right choice because it provides
- * the following additional features:
- * - less error prone: doing the same operation with .reverse() requires special care:
- * \code m = m.reverse().eval(); \endcode
- * - this API allows to avoid creating a temporary (the current implementation creates a temporary, but that could be avoided using swap)
- * - it allows future optimizations (cache friendliness, etc.)
- *
- * \sa reverse() */
- template<typename Derived>
- inline void DenseBase<Derived>::reverseInPlace()
- {
- derived() = derived().reverse().eval();
- }
- #endif // EIGEN_REVERSE_H