| 1 | ///////////////////////////////////////////////////////////////////////////// |
| 2 | // Name: matrix.h |
| 3 | // Purpose: wxTransformMatrix class. NOT YET USED |
| 4 | // Author: Chris Breeze, Julian Smart |
| 5 | // Modified by: |
| 6 | // Created: 01/02/97 |
| 7 | // RCS-ID: $Id$ |
| 8 | // Copyright: (c) Julian Smart and Markus Holzem |
| 9 | // Licence: wxWindows licence |
| 10 | ///////////////////////////////////////////////////////////////////////////// |
| 11 | |
| 12 | #ifndef _WX_MATRIXH__ |
| 13 | #define _WX_MATRIXH__ |
| 14 | |
| 15 | #ifdef __GNUG__ |
| 16 | #pragma interface "matrix.h" |
| 17 | #endif |
| 18 | |
| 19 | #include "wx/object.h" |
| 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 | class WXDLLEXPORT wxTransformMatrix: public wxObject |
| 28 | { |
| 29 | public: |
| 30 | wxTransformMatrix(void); |
| 31 | wxTransformMatrix(const wxTransformMatrix& mat); |
| 32 | |
| 33 | double GetValue(int row, int col) const; |
| 34 | void SetValue(int row, int col, double value); |
| 35 | |
| 36 | void operator = (const wxTransformMatrix& mat); |
| 37 | bool operator == (const wxTransformMatrix& mat); |
| 38 | bool operator != (const wxTransformMatrix& mat); |
| 39 | |
| 40 | double& operator()(int row, int col); |
| 41 | double operator()(int row, int col) const; |
| 42 | |
| 43 | // Invert matrix |
| 44 | bool Invert(void); |
| 45 | |
| 46 | // Make into identity matrix |
| 47 | bool Identity(void); |
| 48 | |
| 49 | // Is the matrix the identity matrix? |
| 50 | // Only returns a flag, which is set whenever an operation |
| 51 | // is done. |
| 52 | inline bool IsIdentity(void) const { return m_isIdentity; }; |
| 53 | |
| 54 | // This does an actual check. |
| 55 | inline bool IsIdentity1(void) const ; |
| 56 | |
| 57 | // Isotropic scaling |
| 58 | bool Scale(double scale); |
| 59 | |
| 60 | // Translate |
| 61 | bool Translate(double x, double y); |
| 62 | |
| 63 | // Rotate |
| 64 | bool Rotate(double angle); |
| 65 | |
| 66 | // Transform X value from logical to device |
| 67 | inline double TransformX(double x) const; |
| 68 | |
| 69 | // Transform Y value from logical to device |
| 70 | inline double TransformY(double y) const; |
| 71 | |
| 72 | // Transform a point from logical to device coordinates |
| 73 | bool TransformPoint(double x, double y, double& tx, double& ty) const; |
| 74 | |
| 75 | // Transform a point from device to logical coordinates. |
| 76 | |
| 77 | // Example of use: |
| 78 | // wxTransformMatrix mat = dc.GetTransformation(); |
| 79 | // mat.Invert(); |
| 80 | // mat.InverseTransformPoint(x, y, x1, y1); |
| 81 | // OR (shorthand:) |
| 82 | // dc.LogicalToDevice(x, y, x1, y1); |
| 83 | // The latter is slightly less efficient if we're doing several |
| 84 | // conversions, since the matrix is inverted several times. |
| 85 | |
| 86 | // N.B. 'this' matrix is the inverse at this point |
| 87 | |
| 88 | bool InverseTransformPoint(double x, double y, double& tx, double& ty) const; |
| 89 | |
| 90 | public: |
| 91 | double m_matrix[3][3]; |
| 92 | bool m_isIdentity; |
| 93 | /* |
| 94 | double m11, m21, m31; |
| 95 | double m12, m22, m32; |
| 96 | double m13, m23, m33; |
| 97 | */ |
| 98 | }; |
| 99 | |
| 100 | |
| 101 | /* |
| 102 | The code is wrong and doesn't compile. Chris Breeze als reported, that |
| 103 | some functions of wxTransformMatrix cannot work because it is not |
| 104 | known if he matrix has been inverted. Be careful when using it. |
| 105 | |
| 106 | // Transform X value from logical to device |
| 107 | inline double wxTransformMatrix::TransformX(double x) const |
| 108 | { |
| 109 | return (m_isIdentity ? x : (x * m_matrix[0][0] + y * m_matrix[1][0] + m_matrix[2][0])); |
| 110 | } |
| 111 | |
| 112 | // Transform Y value from logical to device |
| 113 | inline double wxTransformMatrix::TransformY(double y) const |
| 114 | { |
| 115 | return (m_isIdentity ? y : (x * m_matrix[0][1] + y * m_matrix[1][1] + m_matrix[2][1])); |
| 116 | } |
| 117 | */ |
| 118 | |
| 119 | // Is the matrix the identity matrix? |
| 120 | // Perhaps there's some kind of optimization we can do to make this |
| 121 | // a faster operation. E.g. each operation (scale, translate etc.) |
| 122 | // checks whether it's still the identity matrix and sets a flag. |
| 123 | inline bool wxTransformMatrix::IsIdentity1(void) const |
| 124 | { |
| 125 | return |
| 126 | (m_matrix[0][0] == 1.0 && |
| 127 | m_matrix[1][1] == 1.0 && |
| 128 | m_matrix[2][2] == 1.0 && |
| 129 | m_matrix[1][0] == 0.0 && |
| 130 | m_matrix[2][0] == 0.0 && |
| 131 | m_matrix[0][1] == 0.0 && |
| 132 | m_matrix[2][1] == 0.0 && |
| 133 | m_matrix[0][2] == 0.0 && |
| 134 | m_matrix[1][2] == 0.0) ; |
| 135 | } |
| 136 | |
| 137 | // Calculates the determinant of a 2 x 2 matrix |
| 138 | inline double wxCalculateDet(double a11, double a21, double a12, double a22) |
| 139 | { |
| 140 | return a11 * a22 - a12 * a21; |
| 141 | } |
| 142 | |
| 143 | #endif |
| 144 | // _WX_MATRIXH__ |