Homogeneous.h 11.4 KB
Newer Older
LM's avatar
LM committed
1 2 3 4 5
// This file is part of Eigen, a lightweight C++ template library
// for linear algebra.
//
// Copyright (C) 2009-2010 Gael Guennebaud <gael.guennebaud@inria.fr>
//
Don Gagne's avatar
Don Gagne committed
6 7 8
// 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/.
LM's avatar
LM committed
9 10 11 12

#ifndef EIGEN_HOMOGENEOUS_H
#define EIGEN_HOMOGENEOUS_H

Don Gagne's avatar
Don Gagne committed
13 14
namespace Eigen { 

LM's avatar
LM committed
15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61
/** \geometry_module \ingroup Geometry_Module
  *
  * \class Homogeneous
  *
  * \brief Expression of one (or a set of) homogeneous vector(s)
  *
  * \param MatrixType the type of the object in which we are making homogeneous
  *
  * This class represents an expression of one (or a set of) homogeneous vector(s).
  * It is the return type of MatrixBase::homogeneous() and most of the time
  * this is the only way it is used.
  *
  * \sa MatrixBase::homogeneous()
  */

namespace internal {

template<typename MatrixType,int Direction>
struct traits<Homogeneous<MatrixType,Direction> >
 : traits<MatrixType>
{
  typedef typename traits<MatrixType>::StorageKind StorageKind;
  typedef typename nested<MatrixType>::type MatrixTypeNested;
  typedef typename remove_reference<MatrixTypeNested>::type _MatrixTypeNested;
  enum {
    RowsPlusOne = (MatrixType::RowsAtCompileTime != Dynamic) ?
                  int(MatrixType::RowsAtCompileTime) + 1 : Dynamic,
    ColsPlusOne = (MatrixType::ColsAtCompileTime != Dynamic) ?
                  int(MatrixType::ColsAtCompileTime) + 1 : Dynamic,
    RowsAtCompileTime = Direction==Vertical  ?  RowsPlusOne : MatrixType::RowsAtCompileTime,
    ColsAtCompileTime = Direction==Horizontal ? ColsPlusOne : MatrixType::ColsAtCompileTime,
    MaxRowsAtCompileTime = RowsAtCompileTime,
    MaxColsAtCompileTime = ColsAtCompileTime,
    TmpFlags = _MatrixTypeNested::Flags & HereditaryBits,
    Flags = ColsAtCompileTime==1 ? (TmpFlags & ~RowMajorBit)
          : RowsAtCompileTime==1 ? (TmpFlags | RowMajorBit)
          : TmpFlags,
    CoeffReadCost = _MatrixTypeNested::CoeffReadCost
  };
};

template<typename MatrixType,typename Lhs> struct homogeneous_left_product_impl;
template<typename MatrixType,typename Rhs> struct homogeneous_right_product_impl;

} // end namespace internal

template<typename MatrixType,int _Direction> class Homogeneous
Don Gagne's avatar
Don Gagne committed
62
  : internal::no_assignment_operator, public MatrixBase<Homogeneous<MatrixType,_Direction> >
LM's avatar
LM committed
63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81
{
  public:

    enum { Direction = _Direction };

    typedef MatrixBase<Homogeneous> Base;
    EIGEN_DENSE_PUBLIC_INTERFACE(Homogeneous)

    inline Homogeneous(const MatrixType& matrix)
      : m_matrix(matrix)
    {}

    inline Index rows() const { return m_matrix.rows() + (int(Direction)==Vertical   ? 1 : 0); }
    inline Index cols() const { return m_matrix.cols() + (int(Direction)==Horizontal ? 1 : 0); }

    inline Scalar coeff(Index row, Index col) const
    {
      if(  (int(Direction)==Vertical   && row==m_matrix.rows())
        || (int(Direction)==Horizontal && col==m_matrix.cols()))
82
        return Scalar(1);
LM's avatar
LM committed
83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110
      return m_matrix.coeff(row, col);
    }

    template<typename Rhs>
    inline const internal::homogeneous_right_product_impl<Homogeneous,Rhs>
    operator* (const MatrixBase<Rhs>& rhs) const
    {
      eigen_assert(int(Direction)==Horizontal);
      return internal::homogeneous_right_product_impl<Homogeneous,Rhs>(m_matrix,rhs.derived());
    }

    template<typename Lhs> friend
    inline const internal::homogeneous_left_product_impl<Homogeneous,Lhs>
    operator* (const MatrixBase<Lhs>& lhs, const Homogeneous& rhs)
    {
      eigen_assert(int(Direction)==Vertical);
      return internal::homogeneous_left_product_impl<Homogeneous,Lhs>(lhs.derived(),rhs.m_matrix);
    }

    template<typename Scalar, int Dim, int Mode, int Options> friend
    inline const internal::homogeneous_left_product_impl<Homogeneous,Transform<Scalar,Dim,Mode,Options> >
    operator* (const Transform<Scalar,Dim,Mode,Options>& lhs, const Homogeneous& rhs)
    {
      eigen_assert(int(Direction)==Vertical);
      return internal::homogeneous_left_product_impl<Homogeneous,Transform<Scalar,Dim,Mode,Options> >(lhs,rhs.m_matrix);
    }

  protected:
Don Gagne's avatar
Don Gagne committed
111
    typename MatrixType::Nested m_matrix;
LM's avatar
LM committed
112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205
};

/** \geometry_module
  *
  * \return an expression of the equivalent homogeneous vector
  *
  * \only_for_vectors
  *
  * Example: \include MatrixBase_homogeneous.cpp
  * Output: \verbinclude MatrixBase_homogeneous.out
  *
  * \sa class Homogeneous
  */
template<typename Derived>
inline typename MatrixBase<Derived>::HomogeneousReturnType
MatrixBase<Derived>::homogeneous() const
{
  EIGEN_STATIC_ASSERT_VECTOR_ONLY(Derived);
  return derived();
}

/** \geometry_module
  *
  * \returns a matrix expression of homogeneous column (or row) vectors
  *
  * Example: \include VectorwiseOp_homogeneous.cpp
  * Output: \verbinclude VectorwiseOp_homogeneous.out
  *
  * \sa MatrixBase::homogeneous() */
template<typename ExpressionType, int Direction>
inline Homogeneous<ExpressionType,Direction>
VectorwiseOp<ExpressionType,Direction>::homogeneous() const
{
  return _expression();
}

/** \geometry_module
  *
  * \returns an expression of the homogeneous normalized vector of \c *this
  *
  * Example: \include MatrixBase_hnormalized.cpp
  * Output: \verbinclude MatrixBase_hnormalized.out
  *
  * \sa VectorwiseOp::hnormalized() */
template<typename Derived>
inline const typename MatrixBase<Derived>::HNormalizedReturnType
MatrixBase<Derived>::hnormalized() const
{
  EIGEN_STATIC_ASSERT_VECTOR_ONLY(Derived);
  return ConstStartMinusOne(derived(),0,0,
    ColsAtCompileTime==1?size()-1:1,
    ColsAtCompileTime==1?1:size()-1) / coeff(size()-1);
}

/** \geometry_module
  *
  * \returns an expression of the homogeneous normalized vector of \c *this
  *
  * Example: \include DirectionWise_hnormalized.cpp
  * Output: \verbinclude DirectionWise_hnormalized.out
  *
  * \sa MatrixBase::hnormalized() */
template<typename ExpressionType, int Direction>
inline const typename VectorwiseOp<ExpressionType,Direction>::HNormalizedReturnType
VectorwiseOp<ExpressionType,Direction>::hnormalized() const
{
  return HNormalized_Block(_expression(),0,0,
      Direction==Vertical   ? _expression().rows()-1 : _expression().rows(),
      Direction==Horizontal ? _expression().cols()-1 : _expression().cols()).cwiseQuotient(
      Replicate<HNormalized_Factors,
                Direction==Vertical   ? HNormalized_SizeMinusOne : 1,
                Direction==Horizontal ? HNormalized_SizeMinusOne : 1>
        (HNormalized_Factors(_expression(),
          Direction==Vertical    ? _expression().rows()-1:0,
          Direction==Horizontal  ? _expression().cols()-1:0,
          Direction==Vertical    ? 1 : _expression().rows(),
          Direction==Horizontal  ? 1 : _expression().cols()),
         Direction==Vertical   ? _expression().rows()-1 : 1,
         Direction==Horizontal ? _expression().cols()-1 : 1));
}

namespace internal {

template<typename MatrixOrTransformType>
struct take_matrix_for_product
{
  typedef MatrixOrTransformType type;
  static const type& run(const type &x) { return x; }
};

template<typename Scalar, int Dim, int Mode,int Options>
struct take_matrix_for_product<Transform<Scalar, Dim, Mode, Options> >
{
  typedef Transform<Scalar, Dim, Mode, Options> TransformType;
Don Gagne's avatar
Don Gagne committed
206 207
  typedef typename internal::add_const<typename TransformType::ConstAffinePart>::type type;
  static type run (const TransformType& x) { return x.affine(); }
LM's avatar
LM committed
208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259
};

template<typename Scalar, int Dim, int Options>
struct take_matrix_for_product<Transform<Scalar, Dim, Projective, Options> >
{
  typedef Transform<Scalar, Dim, Projective, Options> TransformType;
  typedef typename TransformType::MatrixType type;
  static const type& run (const TransformType& x) { return x.matrix(); }
};

template<typename MatrixType,typename Lhs>
struct traits<homogeneous_left_product_impl<Homogeneous<MatrixType,Vertical>,Lhs> >
{
  typedef typename take_matrix_for_product<Lhs>::type LhsMatrixType;
  typedef typename remove_all<MatrixType>::type MatrixTypeCleaned;
  typedef typename remove_all<LhsMatrixType>::type LhsMatrixTypeCleaned;
  typedef typename make_proper_matrix_type<
                 typename traits<MatrixTypeCleaned>::Scalar,
                 LhsMatrixTypeCleaned::RowsAtCompileTime,
                 MatrixTypeCleaned::ColsAtCompileTime,
                 MatrixTypeCleaned::PlainObject::Options,
                 LhsMatrixTypeCleaned::MaxRowsAtCompileTime,
                 MatrixTypeCleaned::MaxColsAtCompileTime>::type ReturnType;
};

template<typename MatrixType,typename Lhs>
struct homogeneous_left_product_impl<Homogeneous<MatrixType,Vertical>,Lhs>
  : public ReturnByValue<homogeneous_left_product_impl<Homogeneous<MatrixType,Vertical>,Lhs> >
{
  typedef typename traits<homogeneous_left_product_impl>::LhsMatrixType LhsMatrixType;
  typedef typename remove_all<LhsMatrixType>::type LhsMatrixTypeCleaned;
  typedef typename remove_all<typename LhsMatrixTypeCleaned::Nested>::type LhsMatrixTypeNested;
  typedef typename MatrixType::Index Index;
  homogeneous_left_product_impl(const Lhs& lhs, const MatrixType& rhs)
    : m_lhs(take_matrix_for_product<Lhs>::run(lhs)),
      m_rhs(rhs)
  {}

  inline Index rows() const { return m_lhs.rows(); }
  inline Index cols() const { return m_rhs.cols(); }

  template<typename Dest> void evalTo(Dest& dst) const
  {
    // FIXME investigate how to allow lazy evaluation of this product when possible
    dst = Block<const LhsMatrixTypeNested,
              LhsMatrixTypeNested::RowsAtCompileTime,
              LhsMatrixTypeNested::ColsAtCompileTime==Dynamic?Dynamic:LhsMatrixTypeNested::ColsAtCompileTime-1>
            (m_lhs,0,0,m_lhs.rows(),m_lhs.cols()-1) * m_rhs;
    dst += m_lhs.col(m_lhs.cols()-1).rowwise()
            .template replicate<MatrixType::ColsAtCompileTime>(m_rhs.cols());
  }

Don Gagne's avatar
Don Gagne committed
260 261
  typename LhsMatrixTypeCleaned::Nested m_lhs;
  typename MatrixType::Nested m_rhs;
LM's avatar
LM committed
262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298
};

template<typename MatrixType,typename Rhs>
struct traits<homogeneous_right_product_impl<Homogeneous<MatrixType,Horizontal>,Rhs> >
{
  typedef typename make_proper_matrix_type<typename traits<MatrixType>::Scalar,
                 MatrixType::RowsAtCompileTime,
                 Rhs::ColsAtCompileTime,
                 MatrixType::PlainObject::Options,
                 MatrixType::MaxRowsAtCompileTime,
                 Rhs::MaxColsAtCompileTime>::type ReturnType;
};

template<typename MatrixType,typename Rhs>
struct homogeneous_right_product_impl<Homogeneous<MatrixType,Horizontal>,Rhs>
  : public ReturnByValue<homogeneous_right_product_impl<Homogeneous<MatrixType,Horizontal>,Rhs> >
{
  typedef typename remove_all<typename Rhs::Nested>::type RhsNested;
  typedef typename MatrixType::Index Index;
  homogeneous_right_product_impl(const MatrixType& lhs, const Rhs& rhs)
    : m_lhs(lhs), m_rhs(rhs)
  {}

  inline Index rows() const { return m_lhs.rows(); }
  inline Index cols() const { return m_rhs.cols(); }

  template<typename Dest> void evalTo(Dest& dst) const
  {
    // FIXME investigate how to allow lazy evaluation of this product when possible
    dst = m_lhs * Block<const RhsNested,
                        RhsNested::RowsAtCompileTime==Dynamic?Dynamic:RhsNested::RowsAtCompileTime-1,
                        RhsNested::ColsAtCompileTime>
            (m_rhs,0,0,m_rhs.rows()-1,m_rhs.cols());
    dst += m_rhs.row(m_rhs.rows()-1).colwise()
            .template replicate<MatrixType::RowsAtCompileTime>(m_lhs.rows());
  }

Don Gagne's avatar
Don Gagne committed
299 300
  typename MatrixType::Nested m_lhs;
  typename Rhs::Nested m_rhs;
LM's avatar
LM committed
301 302 303 304
};

} // end namespace internal

Don Gagne's avatar
Don Gagne committed
305 306
} // end namespace Eigen

LM's avatar
LM committed
307
#endif // EIGEN_HOMOGENEOUS_H