| 1 | ///////////////////////////////////////////////////////////////////////////// |
| 2 | // Name: wx/matrix.h |
| 3 | // Purpose: wxTransformMatrix class. NOT YET USED |
| 4 | // Author: Chris Breeze, Julian Smart |
| 5 | // Modified by: Klaas Holwerda |
| 6 | // Created: 01/02/97 |
| 7 | // RCS-ID: $Id$ |
| 8 | // Copyright: (c) Julian Smart, Chris Breeze |
| 9 | // Licence: wxWindows licence |
| 10 | ///////////////////////////////////////////////////////////////////////////// |
| 11 | |
| 12 | #ifndef _WX_MATRIXH__ |
| 13 | #define _WX_MATRIXH__ |
| 14 | |
| 15 | //! headerfiles="matrix.h wx/object.h" |
| 16 | #include "wx/object.h" |
| 17 | #include "wx/math.h" |
| 18 | |
| 19 | //! codefiles="matrix.cpp" |
| 20 | |
| 21 | // A simple 3x3 matrix. This may be replaced by a more general matrix |
| 22 | // class some day. |
| 23 | // |
| 24 | // Note: this is intended to be used in wxDC at some point to replace |
| 25 | // the current system of scaling/translation. It is not yet used. |
| 26 | |
| 27 | //:definition |
| 28 | // A 3x3 matrix to do 2D transformations. |
| 29 | // It can be used to map data to window coordinates, |
| 30 | // and also for manipulating your own data. |
| 31 | // For example drawing a picture (composed of several primitives) |
| 32 | // at a certain coordinate and angle within another parent picture. |
| 33 | // At all times m_isIdentity is set if the matrix itself is an Identity matrix. |
| 34 | // It is used where possible to optimize calculations. |
| 35 | class WXDLLEXPORT wxTransformMatrix: public wxObject |
| 36 | { |
| 37 | public: |
| 38 | wxTransformMatrix(void); |
| 39 | wxTransformMatrix(const wxTransformMatrix& mat); |
| 40 | |
| 41 | //get the value in the matrix at col,row |
| 42 | //rows are horizontal (second index of m_matrix member) |
| 43 | //columns are vertical (first index of m_matrix member) |
| 44 | double GetValue(int col, int row) const; |
| 45 | |
| 46 | //set the value in the matrix at col,row |
| 47 | //rows are horizontal (second index of m_matrix member) |
| 48 | //columns are vertical (first index of m_matrix member) |
| 49 | void SetValue(int col, int row, double value); |
| 50 | |
| 51 | void operator = (const wxTransformMatrix& mat); |
| 52 | bool operator == (const wxTransformMatrix& mat) const; |
| 53 | bool operator != (const wxTransformMatrix& mat) const; |
| 54 | |
| 55 | //multiply every element by t |
| 56 | wxTransformMatrix& operator*=(const double& t); |
| 57 | //divide every element by t |
| 58 | wxTransformMatrix& operator/=(const double& t); |
| 59 | //add matrix m to this t |
| 60 | wxTransformMatrix& operator+=(const wxTransformMatrix& m); |
| 61 | //subtract matrix m from this |
| 62 | wxTransformMatrix& operator-=(const wxTransformMatrix& m); |
| 63 | //multiply matrix m with this |
| 64 | wxTransformMatrix& operator*=(const wxTransformMatrix& m); |
| 65 | |
| 66 | // constant operators |
| 67 | |
| 68 | //multiply every element by t and return result |
| 69 | wxTransformMatrix operator*(const double& t) const; |
| 70 | //divide this matrix by t and return result |
| 71 | wxTransformMatrix operator/(const double& t) const; |
| 72 | //add matrix m to this and return result |
| 73 | wxTransformMatrix operator+(const wxTransformMatrix& m) const; |
| 74 | //subtract matrix m from this and return result |
| 75 | wxTransformMatrix operator-(const wxTransformMatrix& m) const; |
| 76 | //multiply this by matrix m and return result |
| 77 | wxTransformMatrix operator*(const wxTransformMatrix& m) const; |
| 78 | wxTransformMatrix operator-() const; |
| 79 | |
| 80 | //rows are horizontal (second index of m_matrix member) |
| 81 | //columns are vertical (first index of m_matrix member) |
| 82 | double& operator()(int col, int row); |
| 83 | |
| 84 | //rows are horizontal (second index of m_matrix member) |
| 85 | //columns are vertical (first index of m_matrix member) |
| 86 | double operator()(int col, int row) const; |
| 87 | |
| 88 | // Invert matrix |
| 89 | bool Invert(void); |
| 90 | |
| 91 | // Make into identity matrix |
| 92 | bool Identity(void); |
| 93 | |
| 94 | // Is the matrix the identity matrix? |
| 95 | // Only returns a flag, which is set whenever an operation |
| 96 | // is done. |
| 97 | inline bool IsIdentity(void) const { return m_isIdentity; } |
| 98 | |
| 99 | // This does an actual check. |
| 100 | inline bool IsIdentity1(void) const ; |
| 101 | |
| 102 | //Scale by scale (isotropic scaling i.e. the same in x and y): |
| 103 | //!ex: |
| 104 | //!code: | scale 0 0 | |
| 105 | //!code: matrix' = | 0 scale 0 | x matrix |
| 106 | //!code: | 0 0 scale | |
| 107 | bool Scale(double scale); |
| 108 | |
| 109 | //Scale with center point and x/y scale |
| 110 | // |
| 111 | //!ex: |
| 112 | //!code: | xs 0 xc(1-xs) | |
| 113 | //!code: matrix' = | 0 ys yc(1-ys) | x matrix |
| 114 | //!code: | 0 0 1 | |
| 115 | wxTransformMatrix& Scale(const double &xs, const double &ys,const double &xc, const double &yc); |
| 116 | |
| 117 | // mirror a matrix in x, y |
| 118 | //!ex: |
| 119 | //!code: | -1 0 0 | |
| 120 | //!code: matrix' = | 0 -1 0 | x matrix |
| 121 | //!code: | 0 0 1 | |
| 122 | wxTransformMatrix& Mirror(bool x=true, bool y=false); |
| 123 | // Translate by dx, dy: |
| 124 | //!ex: |
| 125 | //!code: | 1 0 dx | |
| 126 | //!code: matrix' = | 0 1 dy | x matrix |
| 127 | //!code: | 0 0 1 | |
| 128 | bool Translate(double x, double y); |
| 129 | |
| 130 | // Rotate clockwise by the given number of degrees: |
| 131 | //!ex: |
| 132 | //!code: | cos sin 0 | |
| 133 | //!code: matrix' = | -sin cos 0 | x matrix |
| 134 | //!code: | 0 0 1 | |
| 135 | bool Rotate(double angle); |
| 136 | |
| 137 | //Rotate counter clockwise with point of rotation |
| 138 | // |
| 139 | //!ex: |
| 140 | //!code: | cos(r) -sin(r) x(1-cos(r))+y(sin(r)| |
| 141 | //!code: matrix' = | sin(r) cos(r) y(1-cos(r))-x(sin(r)| x matrix |
| 142 | //!code: | 0 0 1 | |
| 143 | wxTransformMatrix& Rotate(const double &r, const double &x, const double &y); |
| 144 | |
| 145 | // Transform X value from logical to device |
| 146 | inline double TransformX(double x) const; |
| 147 | |
| 148 | // Transform Y value from logical to device |
| 149 | inline double TransformY(double y) const; |
| 150 | |
| 151 | // Transform a point from logical to device coordinates |
| 152 | bool TransformPoint(double x, double y, double& tx, double& ty) const; |
| 153 | |
| 154 | // Transform a point from device to logical coordinates. |
| 155 | // Example of use: |
| 156 | // wxTransformMatrix mat = dc.GetTransformation(); |
| 157 | // mat.Invert(); |
| 158 | // mat.InverseTransformPoint(x, y, x1, y1); |
| 159 | // OR (shorthand:) |
| 160 | // dc.LogicalToDevice(x, y, x1, y1); |
| 161 | // The latter is slightly less efficient if we're doing several |
| 162 | // conversions, since the matrix is inverted several times. |
| 163 | // N.B. 'this' matrix is the inverse at this point |
| 164 | bool InverseTransformPoint(double x, double y, double& tx, double& ty) const; |
| 165 | |
| 166 | double Get_scaleX(); |
| 167 | double Get_scaleY(); |
| 168 | double GetRotation(); |
| 169 | void SetRotation(double rotation); |
| 170 | |
| 171 | |
| 172 | public: |
| 173 | double m_matrix[3][3]; |
| 174 | bool m_isIdentity; |
| 175 | }; |
| 176 | |
| 177 | |
| 178 | /* |
| 179 | Chris Breeze reported, that |
| 180 | some functions of wxTransformMatrix cannot work because it is not |
| 181 | known if he matrix has been inverted. Be careful when using it. |
| 182 | */ |
| 183 | |
| 184 | // Transform X value from logical to device |
| 185 | // warning: this function can only be used for this purpose |
| 186 | // because no rotation is involved when mapping logical to device coordinates |
| 187 | // mirror and scaling for x and y will be part of the matrix |
| 188 | // if you have a matrix that is rotated, eg a shape containing a matrix to place |
| 189 | // it in the logical coordinate system, use TransformPoint |
| 190 | inline double wxTransformMatrix::TransformX(double x) const |
| 191 | { |
| 192 | //normally like this, but since no rotation is involved (only mirror and scale) |
| 193 | //we can do without Y -> m_matrix[1]{0] is -sin(rotation angle) and therefore zero |
| 194 | //(x * m_matrix[0][0] + y * m_matrix[1][0] + m_matrix[2][0])) |
| 195 | return (m_isIdentity ? x : (x * m_matrix[0][0] + m_matrix[2][0])); |
| 196 | } |
| 197 | |
| 198 | // Transform Y value from logical to device |
| 199 | // warning: this function can only be used for this purpose |
| 200 | // because no rotation is involved when mapping logical to device coordinates |
| 201 | // mirror and scaling for x and y will be part of the matrix |
| 202 | // if you have a matrix that is rotated, eg a shape containing a matrix to place |
| 203 | // it in the logical coordinate system, use TransformPoint |
| 204 | inline double wxTransformMatrix::TransformY(double y) const |
| 205 | { |
| 206 | //normally like this, but since no rotation is involved (only mirror and scale) |
| 207 | //we can do without X -> m_matrix[0]{1] is sin(rotation angle) and therefore zero |
| 208 | //(x * m_matrix[0][1] + y * m_matrix[1][1] + m_matrix[2][1])) |
| 209 | return (m_isIdentity ? y : (y * m_matrix[1][1] + m_matrix[2][1])); |
| 210 | } |
| 211 | |
| 212 | |
| 213 | // Is the matrix the identity matrix? |
| 214 | // Each operation checks whether the result is still the identity matrix and sets a flag. |
| 215 | inline bool wxTransformMatrix::IsIdentity1(void) const |
| 216 | { |
| 217 | return |
| 218 | ( wxIsSameDouble(m_matrix[0][0], 1.0) && |
| 219 | wxIsSameDouble(m_matrix[1][1], 1.0) && |
| 220 | wxIsSameDouble(m_matrix[2][2], 1.0) && |
| 221 | wxIsSameDouble(m_matrix[1][0], 0.0) && |
| 222 | wxIsSameDouble(m_matrix[2][0], 0.0) && |
| 223 | wxIsSameDouble(m_matrix[0][1], 0.0) && |
| 224 | wxIsSameDouble(m_matrix[2][1], 0.0) && |
| 225 | wxIsSameDouble(m_matrix[0][2], 0.0) && |
| 226 | wxIsSameDouble(m_matrix[1][2], 0.0) ); |
| 227 | } |
| 228 | |
| 229 | // Calculates the determinant of a 2 x 2 matrix |
| 230 | inline double wxCalculateDet(double a11, double a21, double a12, double a22) |
| 231 | { |
| 232 | return a11 * a22 - a12 * a21; |
| 233 | } |
| 234 | |
| 235 | #endif // _WX_MATRIXH__ |