1 // This file is part of Eigen, a lightweight C++ template library 2 // for linear algebra. 3 // 4 // Copyright (C) 2008 Gael Guennebaud <[email protected]> 5 // 6 // This Source Code Form is subject to the terms of the Mozilla 7 // Public License v. 2.0. If a copy of the MPL was not distributed 8 // with this file, You can obtain one at http://mozilla.org/MPL/2.0/. 9 10 #ifndef EIGEN_TRANSLATION_H 11 #define EIGEN_TRANSLATION_H 12 13 namespace Eigen { 14 15 /** \geometry_module \ingroup Geometry_Module 16 * 17 * \class Translation 18 * 19 * \brief Represents a translation transformation 20 * 21 * \tparam _Scalar the scalar type, i.e., the type of the coefficients. 22 * \tparam _Dim the dimension of the space, can be a compile time value or Dynamic 23 * 24 * \note This class is not aimed to be used to store a translation transformation, 25 * but rather to make easier the constructions and updates of Transform objects. 26 * 27 * \sa class Scaling, class Transform 28 */ 29 template<typename _Scalar, int _Dim> 30 class Translation 31 { 32 public: 33 EIGEN_MAKE_ALIGNED_OPERATOR_NEW_IF_VECTORIZABLE_FIXED_SIZE(_Scalar,_Dim) 34 /** dimension of the space */ 35 enum { Dim = _Dim }; 36 /** the scalar type of the coefficients */ 37 typedef _Scalar Scalar; 38 /** corresponding vector type */ 39 typedef Matrix<Scalar,Dim,1> VectorType; 40 /** corresponding linear transformation matrix type */ 41 typedef Matrix<Scalar,Dim,Dim> LinearMatrixType; 42 /** corresponding affine transformation type */ 43 typedef Transform<Scalar,Dim,Affine> AffineTransformType; 44 /** corresponding isometric transformation type */ 45 typedef Transform<Scalar,Dim,Isometry> IsometryTransformType; 46 47 protected: 48 49 VectorType m_coeffs; 50 51 public: 52 53 /** Default constructor without initialization. */ Translation()54 EIGEN_DEVICE_FUNC Translation() {} 55 /** */ Translation(const Scalar & sx,const Scalar & sy)56 EIGEN_DEVICE_FUNC inline Translation(const Scalar& sx, const Scalar& sy) 57 { 58 eigen_assert(Dim==2); 59 m_coeffs.x() = sx; 60 m_coeffs.y() = sy; 61 } 62 /** */ Translation(const Scalar & sx,const Scalar & sy,const Scalar & sz)63 EIGEN_DEVICE_FUNC inline Translation(const Scalar& sx, const Scalar& sy, const Scalar& sz) 64 { 65 eigen_assert(Dim==3); 66 m_coeffs.x() = sx; 67 m_coeffs.y() = sy; 68 m_coeffs.z() = sz; 69 } 70 /** Constructs and initialize the translation transformation from a vector of translation coefficients */ Translation(const VectorType & vector)71 EIGEN_DEVICE_FUNC explicit inline Translation(const VectorType& vector) : m_coeffs(vector) {} 72 73 /** \brief Returns the x-translation by value. **/ x()74 EIGEN_DEVICE_FUNC inline Scalar x() const { return m_coeffs.x(); } 75 /** \brief Returns the y-translation by value. **/ y()76 EIGEN_DEVICE_FUNC inline Scalar y() const { return m_coeffs.y(); } 77 /** \brief Returns the z-translation by value. **/ z()78 EIGEN_DEVICE_FUNC inline Scalar z() const { return m_coeffs.z(); } 79 80 /** \brief Returns the x-translation as a reference. **/ x()81 EIGEN_DEVICE_FUNC inline Scalar& x() { return m_coeffs.x(); } 82 /** \brief Returns the y-translation as a reference. **/ y()83 EIGEN_DEVICE_FUNC inline Scalar& y() { return m_coeffs.y(); } 84 /** \brief Returns the z-translation as a reference. **/ z()85 EIGEN_DEVICE_FUNC inline Scalar& z() { return m_coeffs.z(); } 86 vector()87 EIGEN_DEVICE_FUNC const VectorType& vector() const { return m_coeffs; } vector()88 EIGEN_DEVICE_FUNC VectorType& vector() { return m_coeffs; } 89 translation()90 EIGEN_DEVICE_FUNC const VectorType& translation() const { return m_coeffs; } translation()91 EIGEN_DEVICE_FUNC VectorType& translation() { return m_coeffs; } 92 93 /** Concatenates two translation */ 94 EIGEN_DEVICE_FUNC inline Translation operator* (const Translation& other) const 95 { return Translation(m_coeffs + other.m_coeffs); } 96 97 /** Concatenates a translation and a uniform scaling */ 98 EIGEN_DEVICE_FUNC inline AffineTransformType operator* (const UniformScaling<Scalar>& other) const; 99 100 /** Concatenates a translation and a linear transformation */ 101 template<typename OtherDerived> 102 EIGEN_DEVICE_FUNC inline AffineTransformType operator* (const EigenBase<OtherDerived>& linear) const; 103 104 /** Concatenates a translation and a rotation */ 105 template<typename Derived> 106 EIGEN_DEVICE_FUNC inline IsometryTransformType operator*(const RotationBase<Derived,Dim>& r) const 107 { return *this * IsometryTransformType(r); } 108 109 /** \returns the concatenation of a linear transformation \a l with the translation \a t */ 110 // its a nightmare to define a templated friend function outside its declaration 111 template<typename OtherDerived> friend 112 EIGEN_DEVICE_FUNC inline AffineTransformType operator*(const EigenBase<OtherDerived>& linear, const Translation& t) 113 { 114 AffineTransformType res; 115 res.matrix().setZero(); 116 res.linear() = linear.derived(); 117 res.translation() = linear.derived() * t.m_coeffs; 118 res.matrix().row(Dim).setZero(); 119 res(Dim,Dim) = Scalar(1); 120 return res; 121 } 122 123 /** Concatenates a translation and a transformation */ 124 template<int Mode, int Options> 125 EIGEN_DEVICE_FUNC inline Transform<Scalar,Dim,Mode> operator* (const Transform<Scalar,Dim,Mode,Options>& t) const 126 { 127 Transform<Scalar,Dim,Mode> res = t; 128 res.pretranslate(m_coeffs); 129 return res; 130 } 131 132 /** Applies translation to vector */ 133 template<typename Derived> 134 inline typename internal::enable_if<Derived::IsVectorAtCompileTime,VectorType>::type 135 operator* (const MatrixBase<Derived>& vec) const 136 { return m_coeffs + vec.derived(); } 137 138 /** \returns the inverse translation (opposite) */ inverse()139 Translation inverse() const { return Translation(-m_coeffs); } 140 Identity()141 static const Translation Identity() { return Translation(VectorType::Zero()); } 142 143 /** \returns \c *this with scalar type casted to \a NewScalarType 144 * 145 * Note that if \a NewScalarType is equal to the current scalar type of \c *this 146 * then this function smartly returns a const reference to \c *this. 147 */ 148 template<typename NewScalarType> cast()149 EIGEN_DEVICE_FUNC inline typename internal::cast_return_type<Translation,Translation<NewScalarType,Dim> >::type cast() const 150 { return typename internal::cast_return_type<Translation,Translation<NewScalarType,Dim> >::type(*this); } 151 152 /** Copy constructor with scalar type conversion */ 153 template<typename OtherScalarType> Translation(const Translation<OtherScalarType,Dim> & other)154 EIGEN_DEVICE_FUNC inline explicit Translation(const Translation<OtherScalarType,Dim>& other) 155 { m_coeffs = other.vector().template cast<Scalar>(); } 156 157 /** \returns \c true if \c *this is approximately equal to \a other, within the precision 158 * determined by \a prec. 159 * 160 * \sa MatrixBase::isApprox() */ 161 EIGEN_DEVICE_FUNC bool isApprox(const Translation& other, const typename NumTraits<Scalar>::Real& prec = NumTraits<Scalar>::dummy_precision()) const 162 { return m_coeffs.isApprox(other.m_coeffs, prec); } 163 164 }; 165 166 /** \addtogroup Geometry_Module */ 167 //@{ 168 typedef Translation<float, 2> Translation2f; 169 typedef Translation<double,2> Translation2d; 170 typedef Translation<float, 3> Translation3f; 171 typedef Translation<double,3> Translation3d; 172 //@} 173 174 template<typename Scalar, int Dim> 175 EIGEN_DEVICE_FUNC inline typename Translation<Scalar,Dim>::AffineTransformType 176 Translation<Scalar,Dim>::operator* (const UniformScaling<Scalar>& other) const 177 { 178 AffineTransformType res; 179 res.matrix().setZero(); 180 res.linear().diagonal().fill(other.factor()); 181 res.translation() = m_coeffs; 182 res(Dim,Dim) = Scalar(1); 183 return res; 184 } 185 186 template<typename Scalar, int Dim> 187 template<typename OtherDerived> 188 EIGEN_DEVICE_FUNC inline typename Translation<Scalar,Dim>::AffineTransformType 189 Translation<Scalar,Dim>::operator* (const EigenBase<OtherDerived>& linear) const 190 { 191 AffineTransformType res; 192 res.matrix().setZero(); 193 res.linear() = linear.derived(); 194 res.translation() = m_coeffs; 195 res.matrix().row(Dim).setZero(); 196 res(Dim,Dim) = Scalar(1); 197 return res; 198 } 199 200 } // end namespace Eigen 201 202 #endif // EIGEN_TRANSLATION_H 203