| 1 | ///////////////////////////////////////////////////////////////////////////// |
| 2 | // Name: matrix.cpp |
| 3 | // Purpose: wxTransformMatrix class |
| 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 | #ifdef __GNUG__ |
| 13 | #pragma implementation "matrix.h" |
| 14 | #endif |
| 15 | |
| 16 | // Note: this is intended to be used in wxDC at some point to replace |
| 17 | // the current system of scaling/translation. It is not yet used. |
| 18 | |
| 19 | // For compilers that support precompilation, includes "wx.h". |
| 20 | #include "wx/wxprec.h" |
| 21 | |
| 22 | #ifdef __BORLANDC__ |
| 23 | #pragma hdrstop |
| 24 | #endif |
| 25 | |
| 26 | #ifndef WX_PRECOMP |
| 27 | #include "wx/defs.h" |
| 28 | #endif |
| 29 | |
| 30 | #include "wx/matrix.h" |
| 31 | #include <math.h> |
| 32 | |
| 33 | const double pi = 3.1415926535; |
| 34 | |
| 35 | wxTransformMatrix::wxTransformMatrix(void) |
| 36 | { |
| 37 | m_isIdentity = FALSE; |
| 38 | |
| 39 | Identity(); |
| 40 | } |
| 41 | |
| 42 | wxTransformMatrix::wxTransformMatrix(const wxTransformMatrix& mat) |
| 43 | { |
| 44 | (*this) = mat; |
| 45 | } |
| 46 | |
| 47 | double wxTransformMatrix::GetValue(int row, int col) const |
| 48 | { |
| 49 | if (row < 0 || row > 2 || col < 0 || col > 2) |
| 50 | return 0.0; |
| 51 | |
| 52 | return m_matrix[row][col]; |
| 53 | } |
| 54 | |
| 55 | void wxTransformMatrix::SetValue(int row, int col, double value) |
| 56 | { |
| 57 | if (row < 0 || row > 2 || col < 0 || col > 2) |
| 58 | return; |
| 59 | |
| 60 | m_matrix[row][col] = value; |
| 61 | } |
| 62 | |
| 63 | void wxTransformMatrix::operator = (const wxTransformMatrix& mat) |
| 64 | { |
| 65 | int i, j; |
| 66 | for (i = 0; i < 3; i++) |
| 67 | { |
| 68 | for (j = 0; j < 3; j++) |
| 69 | { |
| 70 | m_matrix[i][j] = mat.m_matrix[i][j]; |
| 71 | } |
| 72 | } |
| 73 | m_isIdentity = mat.m_isIdentity; |
| 74 | } |
| 75 | |
| 76 | bool wxTransformMatrix::operator == (const wxTransformMatrix& mat) |
| 77 | { |
| 78 | int i, j; |
| 79 | for (i = 0; i < 3; i++) |
| 80 | { |
| 81 | for (j = 0; j < 3; j++) |
| 82 | { |
| 83 | if (m_matrix[i][j] != mat.m_matrix[i][j]) |
| 84 | return FALSE; |
| 85 | } |
| 86 | } |
| 87 | return TRUE; |
| 88 | } |
| 89 | |
| 90 | bool wxTransformMatrix::operator != (const wxTransformMatrix& mat) |
| 91 | { |
| 92 | return (! ((*this) == mat)); |
| 93 | } |
| 94 | |
| 95 | double& wxTransformMatrix::operator()(int row, int col) |
| 96 | { |
| 97 | if (row < 0 || row > 2 || col < 0 || col > 2) |
| 98 | return m_matrix[0][0]; |
| 99 | |
| 100 | return m_matrix[row][col]; |
| 101 | } |
| 102 | |
| 103 | double wxTransformMatrix::operator()(int row, int col) const |
| 104 | { |
| 105 | if (row < 0 || row > 2 || col < 0 || col > 2) |
| 106 | return 0.0; |
| 107 | |
| 108 | return m_matrix[row][col]; |
| 109 | } |
| 110 | |
| 111 | // Invert matrix |
| 112 | bool wxTransformMatrix::Invert(void) |
| 113 | { |
| 114 | double inverseMatrix[3][3]; |
| 115 | |
| 116 | // calculate the adjoint |
| 117 | inverseMatrix[0][0] = wxCalculateDet(m_matrix[1][1],m_matrix[2][1],m_matrix[1][2],m_matrix[2][2]); |
| 118 | inverseMatrix[0][1] = -wxCalculateDet(m_matrix[0][1],m_matrix[2][1],m_matrix[0][2],m_matrix[2][2]); |
| 119 | inverseMatrix[0][2] = wxCalculateDet(m_matrix[0][1],m_matrix[1][1],m_matrix[0][2],m_matrix[1][2]); |
| 120 | |
| 121 | inverseMatrix[1][0] = -wxCalculateDet(m_matrix[1][0],m_matrix[2][0],m_matrix[1][2],m_matrix[2][2]); |
| 122 | inverseMatrix[1][1] = wxCalculateDet(m_matrix[0][0],m_matrix[2][0],m_matrix[0][2],m_matrix[2][2]); |
| 123 | inverseMatrix[1][2] = -wxCalculateDet(m_matrix[0][0],m_matrix[1][0],m_matrix[0][2],m_matrix[1][2]); |
| 124 | |
| 125 | inverseMatrix[2][0] = wxCalculateDet(m_matrix[1][0],m_matrix[2][0],m_matrix[1][1],m_matrix[2][1]); |
| 126 | inverseMatrix[2][1] = -wxCalculateDet(m_matrix[0][0],m_matrix[2][0],m_matrix[0][1],m_matrix[2][1]); |
| 127 | inverseMatrix[2][2] = wxCalculateDet(m_matrix[0][0],m_matrix[1][0],m_matrix[0][1],m_matrix[1][1]); |
| 128 | |
| 129 | // now divide by the determinant |
| 130 | double det = m_matrix[0][0] * inverseMatrix[0][0] + m_matrix[0][1] * inverseMatrix[1][0] + m_matrix[0][2] * inverseMatrix[2][0]; |
| 131 | if (det != 0.0) |
| 132 | { |
| 133 | inverseMatrix[0][0] /= det; inverseMatrix[1][0] /= det; inverseMatrix[2][0] /= det; |
| 134 | inverseMatrix[0][1] /= det; inverseMatrix[1][1] /= det; inverseMatrix[2][1] /= det; |
| 135 | inverseMatrix[0][2] /= det; inverseMatrix[1][2] /= det; inverseMatrix[2][2] /= det; |
| 136 | |
| 137 | int i, j; |
| 138 | for (i = 0; i < 3; i++) |
| 139 | { |
| 140 | for (j = 0; j < 3; j++) |
| 141 | { |
| 142 | m_matrix[i][j] = inverseMatrix[i][j]; |
| 143 | } |
| 144 | } |
| 145 | m_isIdentity = IsIdentity1(); |
| 146 | return TRUE; |
| 147 | } |
| 148 | else |
| 149 | { |
| 150 | return FALSE; |
| 151 | } |
| 152 | } |
| 153 | |
| 154 | // Make into identity matrix |
| 155 | bool wxTransformMatrix::Identity(void) |
| 156 | { |
| 157 | m_matrix[0][0] = m_matrix[1][1] = m_matrix[2][2] = 1.0; |
| 158 | m_matrix[1][0] = m_matrix[2][0] = m_matrix[0][1] = m_matrix[2][1] = m_matrix[0][2] = m_matrix[1][2] = 0.0; |
| 159 | m_isIdentity = TRUE; |
| 160 | |
| 161 | return TRUE; |
| 162 | } |
| 163 | |
| 164 | // Scale by scale (isotropic scaling i.e. the same in x and y): |
| 165 | // | scale 0 0 | |
| 166 | // matrix' = | 0 scale 0 | x matrix |
| 167 | // | 0 0 scale | |
| 168 | // |
| 169 | bool wxTransformMatrix::Scale(double scale) |
| 170 | { |
| 171 | int i, j; |
| 172 | for (i = 0; i < 3; i++) |
| 173 | { |
| 174 | for (j = 0; j < 3; j++) |
| 175 | { |
| 176 | m_matrix[i][j] *= scale; |
| 177 | } |
| 178 | } |
| 179 | m_isIdentity = IsIdentity1(); |
| 180 | |
| 181 | return TRUE; |
| 182 | } |
| 183 | |
| 184 | // Translate by dx, dy: |
| 185 | // | 1 0 dx | |
| 186 | // matrix' = | 0 1 dy | x matrix |
| 187 | // | 0 0 1 | |
| 188 | // |
| 189 | bool wxTransformMatrix::Translate(double dx, double dy) |
| 190 | { |
| 191 | int i; |
| 192 | for (i = 0; i < 3; i++) |
| 193 | m_matrix[i][0] += dx * m_matrix[i][2]; |
| 194 | for (i = 0; i < 3; i++) |
| 195 | m_matrix[i][1] += dy * m_matrix[i][2]; |
| 196 | |
| 197 | m_isIdentity = IsIdentity1(); |
| 198 | |
| 199 | return TRUE; |
| 200 | } |
| 201 | |
| 202 | // Rotate by the given number of degrees: |
| 203 | // | cos sin 0 | |
| 204 | // matrix' = | -sin cos 0 | x matrix |
| 205 | // | 0 0 1 | |
| 206 | // |
| 207 | bool wxTransformMatrix::Rotate(double degrees) |
| 208 | { |
| 209 | double angle = degrees * pi / 180.0; |
| 210 | double s = sin(angle); |
| 211 | double c = cos(angle); |
| 212 | |
| 213 | m_matrix[0][0] = c * m_matrix[0][0] + s * m_matrix[0][1]; |
| 214 | m_matrix[1][0] = c * m_matrix[1][0] + s * m_matrix[1][1]; |
| 215 | m_matrix[2][0] = c * m_matrix[2][0] + s * m_matrix[2][1]; |
| 216 | m_matrix[0][2] = c * m_matrix[0][1] - s * m_matrix[0][0]; |
| 217 | m_matrix[1][2] = c * m_matrix[1][1] - s * m_matrix[1][0]; |
| 218 | m_matrix[2][2] = c * m_matrix[2][1] - s * m_matrix[2][0]; |
| 219 | |
| 220 | m_isIdentity = IsIdentity1(); |
| 221 | |
| 222 | return TRUE; |
| 223 | } |
| 224 | |
| 225 | // Transform a point from logical to device coordinates |
| 226 | bool wxTransformMatrix::TransformPoint(double x, double y, double& tx, double& ty) const |
| 227 | { |
| 228 | if (IsIdentity()) |
| 229 | { |
| 230 | tx = x; ty = y; return TRUE; |
| 231 | } |
| 232 | |
| 233 | tx = x * m_matrix[0][0] + y * m_matrix[1][0] + m_matrix[2][0]; |
| 234 | ty = x * m_matrix[0][1] + y * m_matrix[1][1] + m_matrix[2][1]; |
| 235 | |
| 236 | return TRUE; |
| 237 | } |
| 238 | |
| 239 | // Transform a point from device to logical coordinates. |
| 240 | |
| 241 | // Example of use: |
| 242 | // wxTransformMatrix mat = dc.GetTransformation(); |
| 243 | // mat.Invert(); |
| 244 | // mat.InverseTransformPoint(x, y, x1, y1); |
| 245 | // OR (shorthand:) |
| 246 | // dc.LogicalToDevice(x, y, x1, y1); |
| 247 | // The latter is slightly less efficient if we're doing several |
| 248 | // conversions, since the matrix is inverted several times. |
| 249 | |
| 250 | bool wxTransformMatrix::InverseTransformPoint(double x, double y, double& tx, double& ty) const |
| 251 | { |
| 252 | if (IsIdentity()) |
| 253 | { |
| 254 | tx = x; ty = y; return TRUE; |
| 255 | } |
| 256 | |
| 257 | double z = (1.0 - m_matrix[0][2] * x - m_matrix[1][2] * y) / m_matrix[2][2]; |
| 258 | if (z == 0.0) |
| 259 | { |
| 260 | // z = 0.0000001; |
| 261 | return FALSE; |
| 262 | } |
| 263 | tx = x * m_matrix[0][0] + y * m_matrix[1][0] + z * m_matrix[2][0]; |
| 264 | ty = x * m_matrix[0][1] + y * m_matrix[1][1] + z * m_matrix[2][1]; |
| 265 | return TRUE; |
| 266 | } |
| 267 | |