| 1 | \section{\class{wxDC}}\label{wxdc} |
| 2 | |
| 3 | A wxDC is a {\it device context} onto which graphics and text can be drawn. |
| 4 | It is intended to represent a number of output devices in a generic way, |
| 5 | so a window can have a device context associated with it, and a printer also has a device context. |
| 6 | In this way, the same piece of code may write to a number of different devices, |
| 7 | if the device context is used as a parameter. |
| 8 | |
| 9 | Derived types of wxDC have documentation for specific features |
| 10 | only, so refer to this section for most device context information. |
| 11 | |
| 12 | % VZ: we should really document them instead of this lame excuse, but I don't |
| 13 | % have time for it now, when it is done please remove this |
| 14 | Please note that in addition to the versions of the methods documented here, |
| 15 | there are also versions which accept single {\tt wxPoint} parameter instead of |
| 16 | two {\tt wxCoord} ones or {\tt wxPoint} and {\tt wxSize} instead of four of |
| 17 | them. |
| 18 | |
| 19 | \wxheading{Derived from} |
| 20 | |
| 21 | \helpref{wxObject}{wxobject} |
| 22 | |
| 23 | \wxheading{Include files} |
| 24 | |
| 25 | <wx/dc.h> |
| 26 | |
| 27 | \wxheading{See also} |
| 28 | |
| 29 | \helpref{Overview}{dcoverview} |
| 30 | |
| 31 | \latexignore{\rtfignore{\wxheading{Members}}} |
| 32 | |
| 33 | \membersection{wxDC::wxDC} |
| 34 | |
| 35 | \func{}{wxDC}{\void} |
| 36 | |
| 37 | Constructor. |
| 38 | |
| 39 | \membersection{wxDC::\destruct{wxDC}} |
| 40 | |
| 41 | \func{}{\destruct{wxDC}}{\void} |
| 42 | |
| 43 | Destructor. |
| 44 | |
| 45 | \membersection{wxDC::BeginDrawing}\label{wxdcbegindrawing} |
| 46 | |
| 47 | \func{void}{BeginDrawing}{\void} |
| 48 | |
| 49 | Allows optimization of drawing code under MS Windows. Enclose |
| 50 | drawing primitives between {\bf BeginDrawing} and {\bf EndDrawing}\rtfsp |
| 51 | calls. |
| 52 | |
| 53 | Drawing to a wxDialog panel device context outside of a |
| 54 | system-generated OnPaint event {\it requires} this pair of calls to |
| 55 | enclose drawing code. This is because a Windows dialog box does not have |
| 56 | a retained device context associated with it, and selections such as pen |
| 57 | and brush settings would be lost if the device context were obtained and |
| 58 | released for each drawing operation. |
| 59 | |
| 60 | \membersection{wxDC::Blit}\label{wxdcblit} |
| 61 | |
| 62 | \func{bool}{Blit}{\param{wxCoord}{ xdest}, \param{wxCoord}{ ydest}, \param{wxCoord}{ width}, \param{wxCoord}{ height}, |
| 63 | \param{wxDC* }{source}, \param{wxCoord}{ xsrc}, \param{wxCoord}{ ysrc}, \param{int}{ logicalFunc = wxCOPY}, |
| 64 | \param{bool }{useMask = FALSE}, \param{wxCoord}{ xsrcMask = -1}, \param{wxCoord}{ ysrcMask = -1}} |
| 65 | |
| 66 | Copy from a source DC to this DC, specifying the destination |
| 67 | coordinates, size of area to copy, source DC, source coordinates, |
| 68 | logical function, whether to use a bitmap mask, and mask source position. |
| 69 | |
| 70 | \wxheading{Parameters} |
| 71 | |
| 72 | \docparam{xdest}{Destination device context x position.} |
| 73 | |
| 74 | \docparam{ydest}{Destination device context y position.} |
| 75 | |
| 76 | \docparam{width}{Width of source area to be copied.} |
| 77 | |
| 78 | \docparam{height}{Height of source area to be copied.} |
| 79 | |
| 80 | \docparam{source}{Source device context.} |
| 81 | |
| 82 | \docparam{xsrc}{Source device context x position.} |
| 83 | |
| 84 | \docparam{ysrc}{Source device context y position.} |
| 85 | |
| 86 | \docparam{logicalFunc}{Logical function to use: see \helpref{wxDC::SetLogicalFunction}{wxdcsetlogicalfunction}.} |
| 87 | |
| 88 | \docparam{useMask}{If TRUE, Blit does a transparent blit using the mask that is associated with the bitmap |
| 89 | selected into the source device context. The Windows implementation does the following if MaskBlt cannot be used: |
| 90 | |
| 91 | \begin{enumerate} |
| 92 | \item Creates a temporary bitmap and copies the destination area into it. |
| 93 | \item Copies the source area into the temporary bitmap using the specified logical function. |
| 94 | \item Sets the masked area in the temporary bitmap to BLACK by ANDing the |
| 95 | mask bitmap with the temp bitmap with the foreground colour set to WHITE |
| 96 | and the bg colour set to BLACK. |
| 97 | \item Sets the unmasked area in the destination area to BLACK by ANDing the |
| 98 | mask bitmap with the destination area with the foreground colour set to BLACK |
| 99 | and the background colour set to WHITE. |
| 100 | \item ORs the temporary bitmap with the destination area. |
| 101 | \item Deletes the temporary bitmap. |
| 102 | \end{enumerate} |
| 103 | |
| 104 | This sequence of operations ensures that the source's transparent area need not be black, |
| 105 | and logical functions are supported. |
| 106 | |
| 107 | {\bf Note:} on Windows, blitting with masks can be speeded up considerably by compiling |
| 108 | wxWindows with the wxUSE\_DC\_CACHE option enabled. You can also influence whether MaskBlt |
| 109 | or the explicit mask blitting code above is used, by using \helpref{wxSystemOptions}{wxsystemoptions} and |
| 110 | setting the {\bf no-maskblt} option to 1. |
| 111 | |
| 112 | } |
| 113 | |
| 114 | \docparam{xsrcMask}{Source x position on the mask. If both xsrcMask and ysrcMask are -1, xsrc and ysrc |
| 115 | will be assumed for the mask source position. Currently only implemented on Windows.} |
| 116 | |
| 117 | \docparam{ysrcMask}{Source y position on the mask. If both xsrcMask and ysrcMask are -1, xsrc and ysrc |
| 118 | will be assumed for the mask source position. Currently only implemented on Windows.} |
| 119 | |
| 120 | |
| 121 | \wxheading{Remarks} |
| 122 | |
| 123 | There is partial support for Blit in wxPostScriptDC, under X. |
| 124 | |
| 125 | See \helpref{wxMemoryDC}{wxmemorydc} for typical usage. |
| 126 | |
| 127 | \wxheading{See also} |
| 128 | |
| 129 | \helpref{wxMemoryDC}{wxmemorydc}, \helpref{wxBitmap}{wxbitmap}, \helpref{wxMask}{wxmask} |
| 130 | |
| 131 | \begin{comment} |
| 132 | \membersection{wxDC::CacheEnabled}\label{wxdccacheenabled} |
| 133 | |
| 134 | \func{static bool}{CacheEnabled}{\void} |
| 135 | |
| 136 | On supported platforms (currently only Windows), returns TRUE |
| 137 | if the DC cache is enabled. The DC cache |
| 138 | can speed up the \helpref{Blit}{wxdcblit} operation when |
| 139 | drawing a large number of masked bitmaps. |
| 140 | |
| 141 | If using the cache functions in your code, please test for the |
| 142 | wxUSE\_DC\_CACHEING preprocessor symbol for portability. |
| 143 | |
| 144 | \wxheading{See also} |
| 145 | |
| 146 | \helpref{wxDC::EnableCache}{wxdcenablecache}, \helpref{wxDC::ClearCache} |
| 147 | \end{comment} |
| 148 | |
| 149 | \membersection{wxDC::CalcBoundingBox}\label{wxdccalcboundingbox} |
| 150 | |
| 151 | \func{void}{CalcBoundingBox}{\param{wxCoord }{x}, \param{wxCoord }{y}} |
| 152 | |
| 153 | Adds the specified point to the bounding box which can be retrieved with |
| 154 | \helpref{MinX}{wxdcminx}, \helpref{MaxX}{wxdcmaxx} and |
| 155 | \helpref{MinY}{wxdcminy}, \helpref{MaxY}{wxdcmaxy} functions. |
| 156 | |
| 157 | \wxheading{See also} |
| 158 | |
| 159 | \helpref{ResetBoundingBox}{wxdcresetboundingbox} |
| 160 | |
| 161 | \membersection{wxDC::Clear}\label{wxdcclear} |
| 162 | |
| 163 | \func{void}{Clear}{\void} |
| 164 | |
| 165 | Clears the device context using the current background brush. |
| 166 | |
| 167 | \begin{comment} |
| 168 | \membersection{wxDC::ClearCache}\label{wxdcclearcache} |
| 169 | |
| 170 | \func{static void}{ClearCache}{\void} |
| 171 | |
| 172 | On supported platforms (currently only Windows), clears |
| 173 | the contents of the DC cache (one bitmap and two Windows device contexts). The DC cache |
| 174 | can speed up the \helpref{Blit}{wxdcblit} operation when |
| 175 | drawing a large number of masked bitmaps. You should |
| 176 | call ClearCache at the end of length DC operations if you wish to only use |
| 177 | the cache transiently; you should also call it as your application exits. |
| 178 | |
| 179 | If using the cache functions in your code, please test for the |
| 180 | wxUSE\_DC\_CACHEING preprocessor symbol for portability. |
| 181 | |
| 182 | \wxheading{See also} |
| 183 | |
| 184 | \helpref{wxDC::EnableCache}{wxdcenablecache}, \helpref{wxDC::CacheEnabled} |
| 185 | \end{comment} |
| 186 | |
| 187 | \membersection{wxDC::CrossHair}\label{wxdccrosshair} |
| 188 | |
| 189 | \func{void}{CrossHair}{\param{wxCoord}{ x}, \param{wxCoord}{ y}} |
| 190 | |
| 191 | Displays a cross hair using the current pen. This is a vertical |
| 192 | and horizontal line the height and width of the window, centred |
| 193 | on the given point. |
| 194 | |
| 195 | \membersection{wxDC::DestroyClippingRegion}\label{wxdcdestroyclippingregion} |
| 196 | |
| 197 | \func{void}{DestroyClippingRegion}{\void} |
| 198 | |
| 199 | Destroys the current clipping region so that none of the DC is clipped. |
| 200 | See also \helpref{wxDC::SetClippingRegion}{wxdcsetclippingregion}. |
| 201 | |
| 202 | \membersection{wxDC::DeviceToLogicalX}\label{wxdcdevicetologicalx} |
| 203 | |
| 204 | \func{wxCoord}{DeviceToLogicalX}{\param{wxCoord}{ x}} |
| 205 | |
| 206 | Convert device X coordinate to logical coordinate, using the current |
| 207 | mapping mode. |
| 208 | |
| 209 | \membersection{wxDC::DeviceToLogicalXRel}\label{wxdcdevicetologicalxrel} |
| 210 | |
| 211 | \func{wxCoord}{DeviceToLogicalXRel}{\param{wxCoord}{ x}} |
| 212 | |
| 213 | Convert device X coordinate to relative logical coordinate, using the current |
| 214 | mapping mode but ignoring the x axis orientation. |
| 215 | Use this function for converting a width, for example. |
| 216 | |
| 217 | \membersection{wxDC::DeviceToLogicalY}\label{wxdcdevicetologicaly} |
| 218 | |
| 219 | \func{wxCoord}{DeviceToLogicalY}{\param{wxCoord}{ y}} |
| 220 | |
| 221 | Converts device Y coordinate to logical coordinate, using the current |
| 222 | mapping mode. |
| 223 | |
| 224 | \membersection{wxDC::DeviceToLogicalYRel}\label{wxdcdevicetologicalyrel} |
| 225 | |
| 226 | \func{wxCoord}{DeviceToLogicalYRel}{\param{wxCoord}{ y}} |
| 227 | |
| 228 | Convert device Y coordinate to relative logical coordinate, using the current |
| 229 | mapping mode but ignoring the y axis orientation. |
| 230 | Use this function for converting a height, for example. |
| 231 | |
| 232 | \membersection{wxDC::DrawArc}\label{wxdcdrawarc} |
| 233 | |
| 234 | \func{void}{DrawArc}{\param{wxCoord}{ x1}, \param{wxCoord}{ y1}, \param{wxCoord}{ x2}, \param{wxCoord}{ y2}, \param{double}{ xc}, \param{double}{ yc}} |
| 235 | |
| 236 | Draws an arc of a circle, centred on ({\it xc, yc}), with starting point ({\it x1, y1}) |
| 237 | and ending at ({\it x2, y2}). The current pen is used for the outline |
| 238 | and the current brush for filling the shape. |
| 239 | |
| 240 | The arc is drawn in an anticlockwise direction from the start point to the end point. |
| 241 | |
| 242 | \membersection{wxDC::DrawBitmap}\label{wxdcdrawbitmap} |
| 243 | |
| 244 | \func{void}{DrawBitmap}{\param{const wxBitmap\&}{ bitmap}, \param{wxCoord}{ x}, \param{wxCoord}{ y}, \param{bool}{ transparent}} |
| 245 | |
| 246 | Draw a bitmap on the device context at the specified point. If {\it transparent} is TRUE and the bitmap has |
| 247 | a transparency mask, the bitmap will be drawn transparently. |
| 248 | |
| 249 | When drawing a mono-bitmap, the current text foreground colour will be used to draw the foreground |
| 250 | of the bitmap (all bits set to 1), and the current text background colour to draw the background |
| 251 | (all bits set to 0). See also \helpref{SetTextForeground}{wxdcsettextforeground}, |
| 252 | \helpref{SetTextBackground}{wxdcsettextbackground} and \helpref{wxMemoryDC}{wxmemorydc}. |
| 253 | |
| 254 | \membersection{wxDC::DrawCheckMark}\label{wxdcdrawcheckmark} |
| 255 | |
| 256 | \func{void}{DrawCheckMark}{\param{wxCoord}{ x}, \param{wxCoord}{ y}, \param{wxCoord}{ width}, \param{wxCoord}{ height}} |
| 257 | |
| 258 | \func{void}{DrawCheckMark}{\param{const wxRect \&}{rect}} |
| 259 | |
| 260 | Draws a check mark inside the given rectangle. |
| 261 | |
| 262 | \membersection{wxDC::DrawCircle}\label{wxdcdrawcircle} |
| 263 | |
| 264 | \func{void}{DrawCircle}{\param{wxCoord}{ x}, \param{wxCoord}{ y}, \param{wxCoord}{ radius}} |
| 265 | |
| 266 | \func{void}{DrawCircle}{\param{const wxPoint\&}{ pt}, \param{wxCoord}{ radius}} |
| 267 | |
| 268 | Draws a circle with the given centre and radius. |
| 269 | |
| 270 | \wxheading{See also} |
| 271 | |
| 272 | \helpref{DrawEllipse}{wxdcdrawellipse} |
| 273 | |
| 274 | \membersection{wxDC::DrawEllipse}\label{wxdcdrawellipse} |
| 275 | |
| 276 | \func{void}{DrawEllipse}{\param{wxCoord}{ x}, \param{wxCoord}{ y}, \param{wxCoord}{ width}, \param{wxCoord}{ height}} |
| 277 | |
| 278 | \func{void}{DrawEllipse}{\param{const wxPoint\&}{ pt}, \param{const wxSize\&}{ size}} |
| 279 | |
| 280 | \func{void}{DrawEllipse}{\param{const wxRect\&}{ rect}} |
| 281 | |
| 282 | Draws an ellipse contained in the rectangle specified either with the given top |
| 283 | left corner and the given size or directly. The current pen is used for the |
| 284 | outline and the current brush for filling the shape. |
| 285 | |
| 286 | \wxheading{See also} |
| 287 | |
| 288 | \helpref{DrawCircle}{wxdcdrawcircle} |
| 289 | |
| 290 | \membersection{wxDC::DrawEllipticArc}\label{wxdcdrawellipticarc} |
| 291 | |
| 292 | \func{void}{DrawEllipticArc}{\param{wxCoord}{ x}, \param{wxCoord}{ y}, \param{wxCoord}{ width}, \param{wxCoord}{ height}, |
| 293 | \param{double}{ start}, \param{double}{ end}} |
| 294 | |
| 295 | Draws an arc of an ellipse. The current pen is used for drawing the arc and |
| 296 | the current brush is used for drawing the pie. |
| 297 | |
| 298 | {\it x} and {\it y} specify the x and y coordinates of the upper-left corner of the rectangle that contains |
| 299 | the ellipse. |
| 300 | |
| 301 | {\it width} and {\it height} specify the width and height of the rectangle that contains |
| 302 | the ellipse. |
| 303 | |
| 304 | {\it start} and {\it end} specify the start and end of the arc relative to the three-o'clock |
| 305 | position from the center of the rectangle. Angles are specified |
| 306 | in degrees (360 is a complete circle). Positive values mean |
| 307 | counter-clockwise motion. If {\it start} is equal to {\it end}, a |
| 308 | complete ellipse will be drawn. |
| 309 | |
| 310 | \membersection{wxDC::DrawIcon}\label{wxdcdrawicon} |
| 311 | |
| 312 | \func{void}{DrawIcon}{\param{const wxIcon\&}{ icon}, \param{wxCoord}{ x}, \param{wxCoord}{ y}} |
| 313 | |
| 314 | Draw an icon on the display (does nothing if the device context is PostScript). |
| 315 | This can be the simplest way of drawing bitmaps on a window. |
| 316 | |
| 317 | \membersection{wxDC::DrawLine}\label{wxdcdrawline} |
| 318 | |
| 319 | \func{void}{DrawLine}{\param{wxCoord}{ x1}, \param{wxCoord}{ y1}, \param{wxCoord}{ x2}, \param{wxCoord}{ y2}} |
| 320 | |
| 321 | Draws a line from the first point to the second. The current pen is used |
| 322 | for drawing the line. |
| 323 | |
| 324 | \membersection{wxDC::DrawLines}\label{wxdcdrawlines} |
| 325 | |
| 326 | \func{void}{DrawLines}{\param{int}{ n}, \param{wxPoint}{ points[]}, \param{wxCoord}{ xoffset = 0}, \param{wxCoord}{ yoffset = 0}} |
| 327 | |
| 328 | \func{void}{DrawLines}{\param{wxList *}{points}, \param{wxCoord}{ xoffset = 0}, \param{wxCoord}{ yoffset = 0}} |
| 329 | |
| 330 | Draws lines using an array of {\it points} of size {\it n}, or list of |
| 331 | pointers to points, adding the optional offset coordinate. The current |
| 332 | pen is used for drawing the lines. The programmer is responsible for |
| 333 | deleting the list of points. |
| 334 | |
| 335 | \pythonnote{The wxPython version of this method accepts a Python list |
| 336 | of wxPoint objects.} |
| 337 | |
| 338 | \perlnote{The wxPerl version of this method accepts |
| 339 | as its first parameter a reference to an array |
| 340 | of wxPoint objects.} |
| 341 | |
| 342 | \membersection{wxDC::DrawPolygon}\label{wxdcdrawpolygon} |
| 343 | |
| 344 | \func{void}{DrawPolygon}{\param{int}{ n}, \param{wxPoint}{ points[]}, \param{wxCoord}{ xoffset = 0}, \param{wxCoord}{ yoffset = 0},\\ |
| 345 | \param{int }{fill\_style = wxODDEVEN\_RULE}} |
| 346 | |
| 347 | \func{void}{DrawPolygon}{\param{wxList *}{points}, \param{wxCoord}{ xoffset = 0}, \param{wxCoord}{ yoffset = 0},\\ |
| 348 | \param{int }{fill\_style = wxODDEVEN\_RULE}} |
| 349 | |
| 350 | Draws a filled polygon using an array of {\it points} of size {\it n}, |
| 351 | or list of pointers to points, adding the optional offset coordinate. |
| 352 | |
| 353 | The last argument specifies the fill rule: {\bf wxODDEVEN\_RULE} (the |
| 354 | default) or {\bf wxWINDING\_RULE}. |
| 355 | |
| 356 | The current pen is used for drawing the outline, and the current brush |
| 357 | for filling the shape. Using a transparent brush suppresses filling. |
| 358 | The programmer is responsible for deleting the list of points. |
| 359 | |
| 360 | Note that wxWindows automatically closes the first and last points. |
| 361 | |
| 362 | \pythonnote{The wxPython version of this method accepts a Python list |
| 363 | of wxPoint objects.} |
| 364 | |
| 365 | \perlnote{The wxPerl version of this method accepts |
| 366 | as its first parameter a reference to an array |
| 367 | of wxPoint objects.} |
| 368 | |
| 369 | \membersection{wxDC::DrawPoint}\label{wxdcdrawpoint} |
| 370 | |
| 371 | \func{void}{DrawPoint}{\param{wxCoord}{ x}, \param{wxCoord}{ y}} |
| 372 | |
| 373 | Draws a point using the current pen. |
| 374 | |
| 375 | \membersection{wxDC::DrawRectangle}\label{wxdcdrawrectangle} |
| 376 | |
| 377 | \func{void}{DrawRectangle}{\param{wxCoord}{ x}, \param{wxCoord}{ y}, \param{wxCoord}{ width}, \param{wxCoord}{ height}} |
| 378 | |
| 379 | Draws a rectangle with the given top left corner, and with the given |
| 380 | size. The current pen is used for the outline and the current brush |
| 381 | for filling the shape. |
| 382 | |
| 383 | \membersection{wxDC::DrawRotatedText}\label{wxdcdrawrotatedtext} |
| 384 | |
| 385 | \func{void}{DrawRotatedText}{\param{const wxString\& }{text}, \param{wxCoord}{ x}, \param{wxCoord}{ y}, \param{double}{ angle}} |
| 386 | |
| 387 | Draws the text rotated by {\it angle} degrees. |
| 388 | |
| 389 | {\bf NB:} Under Win9x only TrueType fonts can be drawn by this function. In |
| 390 | particular, a font different from {\tt wxNORMAL\_FONT} should be used as the |
| 391 | latter is not a TrueType font. {\tt wxSWISS\_FONT} is an example of a font |
| 392 | which is. |
| 393 | |
| 394 | \wxheading{See also} |
| 395 | |
| 396 | \helpref{DrawText}{wxdcdrawtext} |
| 397 | |
| 398 | \membersection{wxDC::DrawRoundedRectangle}\label{wxdcdrawroundedrectangle} |
| 399 | |
| 400 | \func{void}{DrawRoundedRectangle}{\param{wxCoord}{ x}, \param{wxCoord}{ y}, \param{wxCoord}{ width}, \param{wxCoord}{ height}, \param{double}{ radius = 20}} |
| 401 | |
| 402 | Draws a rectangle with the given top left corner, and with the given |
| 403 | size. The corners are quarter-circles using the given radius. The |
| 404 | current pen is used for the outline and the current brush for filling |
| 405 | the shape. |
| 406 | |
| 407 | If {\it radius} is positive, the value is assumed to be the |
| 408 | radius of the rounded corner. If {\it radius} is negative, |
| 409 | the absolute value is assumed to be the {\it proportion} of the smallest |
| 410 | dimension of the rectangle. This means that the corner can be |
| 411 | a sensible size relative to the size of the rectangle, and also avoids |
| 412 | the strange effects X produces when the corners are too big for |
| 413 | the rectangle. |
| 414 | |
| 415 | \membersection{wxDC::DrawSpline}\label{wxdcdrawspline} |
| 416 | |
| 417 | \func{void}{DrawSpline}{\param{wxList *}{points}} |
| 418 | |
| 419 | Draws a spline between all given control points, using the current |
| 420 | pen. Doesn't delete the wxList and contents. The spline is drawn |
| 421 | using a series of lines, using an algorithm taken from the X drawing |
| 422 | program `XFIG'. |
| 423 | |
| 424 | \func{void}{DrawSpline}{\param{wxCoord}{ x1}, \param{wxCoord}{ y1}, \param{wxCoord}{ x2}, \param{wxCoord}{ y2}, \param{wxCoord}{ x3}, \param{wxCoord}{ y3}} |
| 425 | |
| 426 | Draws a three-point spline using the current pen. |
| 427 | |
| 428 | \pythonnote{The wxPython version of this method accepts a Python list |
| 429 | of wxPoint objects.} |
| 430 | |
| 431 | \perlnote{The wxPerl version of this method accepts a reference to an array |
| 432 | of wxPoint objects.} |
| 433 | |
| 434 | \membersection{wxDC::DrawText}\label{wxdcdrawtext} |
| 435 | |
| 436 | \func{void}{DrawText}{\param{const wxString\& }{text}, \param{wxCoord}{ x}, \param{wxCoord}{ y}} |
| 437 | |
| 438 | Draws a text string at the specified point, using the current text font, |
| 439 | and the current text foreground and background colours. |
| 440 | |
| 441 | The coordinates refer to the top-left corner of the rectangle bounding |
| 442 | the string. See \helpref{wxDC::GetTextExtent}{wxdcgettextextent} for how |
| 443 | to get the dimensions of a text string, which can be used to position the |
| 444 | text more precisely. |
| 445 | |
| 446 | {\bf NB:} under wxGTK the current |
| 447 | \helpref{logical function}{wxdcgetlogicalfunction} is used by this function |
| 448 | but it is ignored by wxMSW. Thus, you should avoid using logical functions |
| 449 | with this function in portable programs. |
| 450 | |
| 451 | \begin{comment} |
| 452 | \membersection{wxDC::EnableCache}\label{wxdcenablecache} |
| 453 | |
| 454 | \func{static void}{EnableCache}{\param{bool}{ enableCache}} |
| 455 | |
| 456 | On supported platforms (currently only Windows), enables the DC cache |
| 457 | which can speed up the \helpref{Blit}{wxdcblit} operation when |
| 458 | drawing a large number of masked bitmaps. |
| 459 | |
| 460 | If using the cache functions in your code, please test for the |
| 461 | wxUSE\_DC\_CACHEING preprocessor symbol for portability. |
| 462 | |
| 463 | \wxheading{See also} |
| 464 | |
| 465 | \helpref{wxDC::CacheEnabled}{wxdccacheenabled}, \helpref{wxDC::ClearCache} |
| 466 | \end{comment} |
| 467 | |
| 468 | \membersection{wxDC::EndDoc}\label{wxdcenddoc} |
| 469 | |
| 470 | \func{void}{EndDoc}{\void} |
| 471 | |
| 472 | Ends a document (only relevant when outputting to a printer). |
| 473 | |
| 474 | \membersection{wxDC::EndDrawing}\label{wxdcenddrawing} |
| 475 | |
| 476 | \func{void}{EndDrawing}{\void} |
| 477 | |
| 478 | Allows optimization of drawing code under MS Windows. Enclose |
| 479 | drawing primitives between {\bf BeginDrawing} and {\bf EndDrawing}\rtfsp |
| 480 | calls. |
| 481 | |
| 482 | \membersection{wxDC::EndPage}\label{wxdcendpage} |
| 483 | |
| 484 | \func{void}{EndPage}{\void} |
| 485 | |
| 486 | Ends a document page (only relevant when outputting to a printer). |
| 487 | |
| 488 | \membersection{wxDC::FloodFill}\label{wxdcfloodfill} |
| 489 | |
| 490 | \func{bool}{FloodFill}{\param{wxCoord}{ x}, \param{wxCoord}{ y}, \param{const wxColour\&}{ colour}, \param{int}{ style=wxFLOOD\_SURFACE}} |
| 491 | |
| 492 | Flood fills the device context starting from the given point, using |
| 493 | the {\it current brush colour}, and using a style: |
| 494 | |
| 495 | \begin{itemize}\itemsep=0pt |
| 496 | \item wxFLOOD\_SURFACE: the flooding occurs until a colour other than the given colour is encountered. |
| 497 | \item wxFLOOD\_BORDER: the area to be flooded is bounded by the given colour. |
| 498 | \end{itemize} |
| 499 | |
| 500 | Returns FALSE if the operation failed. |
| 501 | |
| 502 | {\it Note:} The present implementation for non-Windows platforms may fail to find |
| 503 | colour borders if the pixels do not match the colour exactly. However the |
| 504 | function will still return TRUE. |
| 505 | |
| 506 | \membersection{wxDC::GetBackground}\label{wxdcgetbackground} |
| 507 | |
| 508 | \func{wxBrush\&}{GetBackground}{\void} |
| 509 | |
| 510 | \constfunc{const wxBrush\&}{GetBackground}{\void} |
| 511 | |
| 512 | Gets the brush used for painting the background (see \helpref{wxDC::SetBackground}{wxdcsetbackground}). |
| 513 | |
| 514 | \membersection{wxDC::GetBackgroundMode}\label{wxdcgetbackgroundmode} |
| 515 | |
| 516 | \constfunc{int}{GetBackgroundMode}{\void} |
| 517 | |
| 518 | Returns the current background mode: {\tt wxSOLID} or {\tt wxTRANSPARENT}. |
| 519 | |
| 520 | \wxheading{See also} |
| 521 | |
| 522 | \helpref{SetBackgroundMode}{wxdcsetbackgroundmode} |
| 523 | |
| 524 | \membersection{wxDC::GetBrush}\label{wxdcgetbrush} |
| 525 | |
| 526 | \func{wxBrush\&}{GetBrush}{\void} |
| 527 | |
| 528 | \constfunc{const wxBrush\&}{GetBrush}{\void} |
| 529 | |
| 530 | Gets the current brush (see \helpref{wxDC::SetBrush}{wxdcsetbrush}). |
| 531 | |
| 532 | \membersection{wxDC::GetCharHeight}\label{wxdcgetcharheight} |
| 533 | |
| 534 | \func{wxCoord}{GetCharHeight}{\void} |
| 535 | |
| 536 | Gets the character height of the currently set font. |
| 537 | |
| 538 | \membersection{wxDC::GetCharWidth}\label{wxdcgetcharwidth} |
| 539 | |
| 540 | \func{wxCoord}{GetCharWidth}{\void} |
| 541 | |
| 542 | Gets the average character width of the currently set font. |
| 543 | |
| 544 | \membersection{wxDC::GetClippingBox}\label{wxdcgetclippingbox} |
| 545 | |
| 546 | \func{void}{GetClippingBox}{\param{wxCoord}{ *x}, \param{wxCoord}{ *y}, \param{wxCoord}{ *width}, \param{wxCoord}{ *height}} |
| 547 | |
| 548 | Gets the rectangle surrounding the current clipping region. |
| 549 | |
| 550 | \pythonnote{No arguments are required and the four values defining the |
| 551 | rectangle are returned as a tuple.} |
| 552 | |
| 553 | \perlnote{This method takes no arguments and returns a four element list |
| 554 | {\tt ( x, y, width, height )}} |
| 555 | |
| 556 | \membersection{wxDC::GetFont}\label{wxdcgetfont} |
| 557 | |
| 558 | \func{wxFont\&}{GetFont}{\void} |
| 559 | |
| 560 | \constfunc{const wxFont\&}{GetFont}{\void} |
| 561 | |
| 562 | Gets the current font (see \helpref{wxDC::SetFont}{wxdcsetfont}). |
| 563 | |
| 564 | \membersection{wxDC::GetLogicalFunction}\label{wxdcgetlogicalfunction} |
| 565 | |
| 566 | \func{int}{GetLogicalFunction}{\void} |
| 567 | |
| 568 | Gets the current logical function (see \helpref{wxDC::SetLogicalFunction}{wxdcsetlogicalfunction}). |
| 569 | |
| 570 | \membersection{wxDC::GetMapMode}\label{wxdcgetmapmode} |
| 571 | |
| 572 | \func{int}{GetMapMode}{\void} |
| 573 | |
| 574 | Gets the {\it mapping mode} for the device context (see \helpref{wxDC::SetMapMode}{wxdcsetmapmode}). |
| 575 | |
| 576 | \membersection{wxDC::GetOptimization}\label{wxdcgetoptimization} |
| 577 | |
| 578 | \func{bool}{GetOptimization}{\void} |
| 579 | |
| 580 | Returns TRUE if device context optimization is on. |
| 581 | See \helpref{wxDC::SetOptimization}{wxsetoptimization} for details. |
| 582 | |
| 583 | \membersection{wxDC::GetPen}\label{wxdcgetpen} |
| 584 | |
| 585 | \func{wxPen\&}{GetPen}{\void} |
| 586 | |
| 587 | \constfunc{const wxPen\&}{GetPen}{\void} |
| 588 | |
| 589 | Gets the current pen (see \helpref{wxDC::SetPen}{wxdcsetpen}). |
| 590 | |
| 591 | \membersection{wxDC::GetPixel}\label{wxdcgetpixel} |
| 592 | |
| 593 | \func{bool}{GetPixel}{\param{wxCoord}{ x}, \param{wxCoord}{ y}, \param{wxColour *}{colour}} |
| 594 | |
| 595 | Sets {\it colour} to the colour at the specified location. Windows only; an X implementation |
| 596 | is being worked on. Not available for wxPostScriptDC or wxMetafileDC. |
| 597 | |
| 598 | \pythonnote{For wxPython the wxColour value is returned and is not |
| 599 | required as a parameter.} |
| 600 | |
| 601 | \perlnote{This method only takes the parameters {\tt x} and {\tt y} and returns |
| 602 | a Wx::Colour value} |
| 603 | |
| 604 | \membersection{wxDC::GetSize}\label{wxdcgetsize} |
| 605 | |
| 606 | \func{void}{GetSize}{\param{wxCoord *}{width}, \param{wxCoord *}{height}} |
| 607 | |
| 608 | For a PostScript device context, this gets the maximum size of graphics |
| 609 | drawn so far on the device context. |
| 610 | |
| 611 | For a Windows printer device context, this gets the horizontal and vertical |
| 612 | resolution. It can be used to scale graphics to fit the page when using |
| 613 | a Windows printer device context. For example, if {\it maxX} and {\it maxY}\rtfsp |
| 614 | represent the maximum horizontal and vertical `pixel' values used in your |
| 615 | application, the following code will scale the graphic to fit on the |
| 616 | printer page: |
| 617 | |
| 618 | \begin{verbatim} |
| 619 | wxCoord w, h; |
| 620 | dc.GetSize(&w, &h); |
| 621 | double scaleX=(double)(maxX/w); |
| 622 | double scaleY=(double)(maxY/h); |
| 623 | dc.SetUserScale(min(scaleX,scaleY),min(scaleX,scaleY)); |
| 624 | \end{verbatim} |
| 625 | |
| 626 | \pythonnote{In place of a single overloaded method name, wxPython |
| 627 | implements the following methods:\par |
| 628 | \indented{2cm}{\begin{twocollist} |
| 629 | \twocolitem{{\bf GetSize()}}{Returns a wxSize} |
| 630 | \twocolitem{{\bf GetSizeTuple()}}{Returns a 2-tuple (width, height)} |
| 631 | \end{twocollist}} |
| 632 | } |
| 633 | |
| 634 | \perlnote{In place of a single overloaded method, wxPerl uses:\par |
| 635 | \indented{2cm}{\begin{twocollist} |
| 636 | \twocolitem{{\bf GetSize()}}{Returns a Wx::Size} |
| 637 | \twocolitem{{\bf GetSizeWH()}}{Returns a 2-element list |
| 638 | {\tt ( width, height )}} |
| 639 | \end{twocollist} |
| 640 | }} |
| 641 | |
| 642 | \membersection{wxDC::GetTextBackground}\label{wxdcgettextbackground} |
| 643 | |
| 644 | \func{wxColour\&}{GetTextBackground}{\void} |
| 645 | |
| 646 | \constfunc{const wxColour\&}{GetTextBackground}{\void} |
| 647 | |
| 648 | Gets the current text background colour (see \helpref{wxDC::SetTextBackground}{wxdcsettextbackground}). |
| 649 | |
| 650 | \membersection{wxDC::GetTextExtent}\label{wxdcgettextextent} |
| 651 | |
| 652 | \func{void}{GetTextExtent}{\param{const wxString\& }{string}, \param{wxCoord *}{w}, \param{wxCoord *}{h},\\ |
| 653 | \param{wxCoord *}{descent = NULL}, \param{wxCoord *}{externalLeading = NULL}, \param{wxFont *}{font = NULL}} |
| 654 | |
| 655 | Gets the dimensions of the string using the currently selected font. |
| 656 | \rtfsp{\it string} is the text string to measure, {\it w} and {\it h} are |
| 657 | the total width and height respectively, {\it descent} is the |
| 658 | dimension from the baseline of the font to the bottom of the |
| 659 | descender, and {\it externalLeading} is any extra vertical space added |
| 660 | to the font by the font designer (usually is zero). |
| 661 | |
| 662 | The optional parameter {\it font} specifies an alternative |
| 663 | to the currently selected font: but note that this does not |
| 664 | yet work under Windows, so you need to set a font for |
| 665 | the device context first. |
| 666 | |
| 667 | See also \helpref{wxFont}{wxfont}, \helpref{wxDC::SetFont}{wxdcsetfont}. |
| 668 | |
| 669 | \pythonnote{The following methods are implemented in wxPython:\par |
| 670 | \indented{2cm}{\begin{twocollist} |
| 671 | \twocolitem{{\bf GetTextExtent(string)}}{Returns a 2-tuple, (width, height)} |
| 672 | \twocolitem{{\bf GetFullTextExtent(string, font=NULL)}}{Returns a |
| 673 | 4-tuple, (width, height, descent, externalLeading) } |
| 674 | \end{twocollist}} |
| 675 | } |
| 676 | |
| 677 | \perlnote{In wxPerl this method is implemented as |
| 678 | {\bf GetTextExtent( string, font = undef )} returning a four element |
| 679 | array {\tt ( width, height, descent, externalLeading )} |
| 680 | } |
| 681 | |
| 682 | \membersection{wxDC::GetTextForeground}\label{wxdcgettextforeground} |
| 683 | |
| 684 | \func{wxColour\&}{GetTextForeground}{\void} |
| 685 | |
| 686 | \constfunc{const wxColour\&}{GetTextForeground}{\void} |
| 687 | |
| 688 | Gets the current text foreground colour (see \helpref{wxDC::SetTextForeground}{wxdcsettextforeground}). |
| 689 | |
| 690 | |
| 691 | \membersection{wxDC::GetUserScale}\label{wxdcgetuserscale} |
| 692 | |
| 693 | \func{void}{GetUserScale}{\param{double}{ *x}, \param{double}{ *y}} |
| 694 | |
| 695 | Gets the current user scale factor (set by \helpref{SetUserScale}{wxdcsetuserscale}). |
| 696 | |
| 697 | \perlnote{In wxPerl this method takes no arguments and return a two element |
| 698 | array {\tt ( x, y )}} |
| 699 | |
| 700 | \membersection{wxDC::LogicalToDeviceX}\label{wxdclogicaltodevicex} |
| 701 | |
| 702 | \func{wxCoord}{LogicalToDeviceX}{\param{wxCoord}{ x}} |
| 703 | |
| 704 | Converts logical X coordinate to device coordinate, using the current |
| 705 | mapping mode. |
| 706 | |
| 707 | \membersection{wxDC::LogicalToDeviceXRel}\label{wxdclogicaltodevicexrel} |
| 708 | |
| 709 | \func{wxCoord}{LogicalToDeviceXRel}{\param{wxCoord}{ x}} |
| 710 | |
| 711 | Converts logical X coordinate to relative device coordinate, using the current |
| 712 | mapping mode but ignoring the x axis orientation. |
| 713 | Use this for converting a width, for example. |
| 714 | |
| 715 | \membersection{wxDC::LogicalToDeviceY}\label{wxdclogicaltodevicey} |
| 716 | |
| 717 | \func{wxCoord}{LogicalToDeviceY}{\param{wxCoord}{ y}} |
| 718 | |
| 719 | Converts logical Y coordinate to device coordinate, using the current |
| 720 | mapping mode. |
| 721 | |
| 722 | \membersection{wxDC::LogicalToDeviceYRel}\label{wxdclogicaltodeviceyrel} |
| 723 | |
| 724 | \func{wxCoord}{LogicalToDeviceYRel}{\param{wxCoord}{ y}} |
| 725 | |
| 726 | Converts logical Y coordinate to relative device coordinate, using the current |
| 727 | mapping mode but ignoring the y axis orientation. |
| 728 | Use this for converting a height, for example. |
| 729 | |
| 730 | \membersection{wxDC::MaxX}\label{wxdcmaxx} |
| 731 | |
| 732 | \func{wxCoord}{MaxX}{\void} |
| 733 | |
| 734 | Gets the maximum horizontal extent used in drawing commands so far. |
| 735 | |
| 736 | \membersection{wxDC::MaxY}\label{wxdcmaxy} |
| 737 | |
| 738 | \func{wxCoord}{MaxY}{\void} |
| 739 | |
| 740 | Gets the maximum vertical extent used in drawing commands so far. |
| 741 | |
| 742 | \membersection{wxDC::MinX}\label{wxdcminx} |
| 743 | |
| 744 | \func{wxCoord}{MinX}{\void} |
| 745 | |
| 746 | Gets the minimum horizontal extent used in drawing commands so far. |
| 747 | |
| 748 | \membersection{wxDC::MinY}\label{wxdcminy} |
| 749 | |
| 750 | \func{wxCoord}{MinY}{\void} |
| 751 | |
| 752 | Gets the minimum vertical extent used in drawing commands so far. |
| 753 | |
| 754 | \membersection{wxDC::Ok}\label{wxdcok} |
| 755 | |
| 756 | \func{bool}{Ok}{\void} |
| 757 | |
| 758 | Returns TRUE if the DC is ok to use. |
| 759 | |
| 760 | \membersection{wxDC::ResetBoundingBox}\label{wxdcresetboundingbox} |
| 761 | |
| 762 | \func{void}{ResetBoundingBox}{\void} |
| 763 | |
| 764 | Resets the bounding box: after a call to this function, the bounding box |
| 765 | doesn't contain anything. |
| 766 | |
| 767 | \wxheading{See also} |
| 768 | |
| 769 | \helpref{CalcBoundingBox}{wxdccalcboundingbox} |
| 770 | |
| 771 | \membersection{wxDC::SetAxisOrientation}\label{wxdcsetaxisorientation} |
| 772 | |
| 773 | \func{void}{SetAxisOrientation}{\param{bool}{ xLeftRight}, |
| 774 | \param{bool}{ yBottomUp}} |
| 775 | |
| 776 | Sets the x and y axis orientation (i.e., the direction from lowest to |
| 777 | highest values on the axis). The default orientation is the natural |
| 778 | orientation, e.g. x axis from left to right and y axis from bottom up. |
| 779 | |
| 780 | \wxheading{Parameters} |
| 781 | |
| 782 | \docparam{xLeftRight}{True to set the x axis orientation to the natural |
| 783 | left to right orientation, false to invert it.} |
| 784 | |
| 785 | \docparam{yBottomUp}{True to set the y axis orientation to the natural |
| 786 | bottom up orientation, false to invert it.} |
| 787 | |
| 788 | \membersection{wxDC::SetDeviceOrigin}\label{wxdcsetdeviceorigin} |
| 789 | |
| 790 | \func{void}{SetDeviceOrigin}{\param{wxCoord}{ x}, \param{wxCoord}{ y}} |
| 791 | |
| 792 | Sets the device origin (i.e., the origin in pixels after scaling has been |
| 793 | applied). |
| 794 | |
| 795 | This function may be useful in Windows printing |
| 796 | operations for placing a graphic on a page. |
| 797 | |
| 798 | \membersection{wxDC::SetBackground}\label{wxdcsetbackground} |
| 799 | |
| 800 | \func{void}{SetBackground}{\param{const wxBrush\& }{brush}} |
| 801 | |
| 802 | Sets the current background brush for the DC. |
| 803 | |
| 804 | \membersection{wxDC::SetBackgroundMode}\label{wxdcsetbackgroundmode} |
| 805 | |
| 806 | \func{void}{SetBackgroundMode}{\param{int}{ mode}} |
| 807 | |
| 808 | {\it mode} may be one of wxSOLID and wxTRANSPARENT. This setting determines |
| 809 | whether text will be drawn with a background colour or not. |
| 810 | |
| 811 | \membersection{wxDC::SetClippingRegion}\label{wxdcsetclippingregion} |
| 812 | |
| 813 | \func{void}{SetClippingRegion}{\param{wxCoord}{ x}, \param{wxCoord}{ y}, \param{wxCoord}{ width}, \param{wxCoord}{ height}} |
| 814 | |
| 815 | \func{void}{SetClippingRegion}{\param{const wxPoint\& }{pt}, \param{const wxSize\& }{sz}} |
| 816 | |
| 817 | \func{void}{SetClippingRegion}{\param{const wxRect\&}{ rect}} |
| 818 | |
| 819 | \func{void}{SetClippingRegion}{\param{const wxRegion\&}{ region}} |
| 820 | |
| 821 | Sets the clipping region for this device context to the intersection of the |
| 822 | given region described by the parameters of this method and the previously set |
| 823 | clipping region. You should call |
| 824 | \helpref{DestroyClippingRegion}{wxdcdestroyclippingregion} if you want to set |
| 825 | the clipping region exactly to the region specified. |
| 826 | |
| 827 | The clipping region is an area to which drawing is restricted. Possible uses |
| 828 | for the clipping region are for clipping text or for speeding up window redraws |
| 829 | when only a known area of the screen is damaged. |
| 830 | |
| 831 | \wxheading{See also} |
| 832 | |
| 833 | \helpref{wxDC::DestroyClippingRegion}{wxdcdestroyclippingregion}, \helpref{wxRegion}{wxregion} |
| 834 | |
| 835 | \membersection{wxDC::SetPalette}\label{wxdcsetpalette} |
| 836 | |
| 837 | \func{void}{SetPalette}{\param{const wxPalette\& }{palette}} |
| 838 | |
| 839 | If this is a window DC or memory DC, assigns the given palette to the window |
| 840 | or bitmap associated with the DC. If the argument is wxNullPalette, the current |
| 841 | palette is selected out of the device context, and the original palette |
| 842 | restored. |
| 843 | |
| 844 | See \helpref{wxPalette}{wxpalette} for further details. |
| 845 | |
| 846 | \membersection{wxDC::SetBrush}\label{wxdcsetbrush} |
| 847 | |
| 848 | \func{void}{SetBrush}{\param{const wxBrush\& }{brush}} |
| 849 | |
| 850 | Sets the current brush for the DC. |
| 851 | |
| 852 | If the argument is wxNullBrush, the current brush is selected out of the device |
| 853 | context, and the original brush restored, allowing the current brush to |
| 854 | be destroyed safely. |
| 855 | |
| 856 | See also \helpref{wxBrush}{wxbrush}. |
| 857 | |
| 858 | See also \helpref{wxMemoryDC}{wxmemorydc} for the interpretation of colours |
| 859 | when drawing into a monochrome bitmap. |
| 860 | |
| 861 | \membersection{wxDC::SetFont}\label{wxdcsetfont} |
| 862 | |
| 863 | \func{void}{SetFont}{\param{const wxFont\& }{font}} |
| 864 | |
| 865 | Sets the current font for the DC. It must be a valid font, in particular you |
| 866 | should not pass {\tt wxNullFont} to this method. |
| 867 | |
| 868 | See also \helpref{wxFont}{wxfont}. |
| 869 | |
| 870 | \membersection{wxDC::SetLogicalFunction}\label{wxdcsetlogicalfunction} |
| 871 | |
| 872 | \func{void}{SetLogicalFunction}{\param{int}{ function}} |
| 873 | |
| 874 | Sets the current logical function for the device context. This determines how |
| 875 | a source pixel (from a pen or brush colour, or source device context if |
| 876 | using \helpref{wxDC::Blit}{wxdcblit}) combines with a destination pixel in the |
| 877 | current device context. |
| 878 | |
| 879 | The possible values |
| 880 | and their meaning in terms of source and destination pixel values are |
| 881 | as follows: |
| 882 | |
| 883 | \begin{verbatim} |
| 884 | wxAND src AND dst |
| 885 | wxAND_INVERT (NOT src) AND dst |
| 886 | wxAND_REVERSE src AND (NOT dst) |
| 887 | wxCLEAR 0 |
| 888 | wxCOPY src |
| 889 | wxEQUIV (NOT src) XOR dst |
| 890 | wxINVERT NOT dst |
| 891 | wxNAND (NOT src) OR (NOT dst) |
| 892 | wxNOR (NOT src) AND (NOT dst) |
| 893 | wxNO_OP dst |
| 894 | wxOR src OR dst |
| 895 | wxOR_INVERT (NOT src) OR dst |
| 896 | wxOR_REVERSE src OR (NOT dst) |
| 897 | wxSET 1 |
| 898 | wxSRC_INVERT NOT src |
| 899 | wxXOR src XOR dst |
| 900 | \end{verbatim} |
| 901 | |
| 902 | The default is wxCOPY, which simply draws with the current colour. |
| 903 | The others combine the current colour and the background using a |
| 904 | logical operation. wxINVERT is commonly used for drawing rubber bands or |
| 905 | moving outlines, since drawing twice reverts to the original colour. |
| 906 | |
| 907 | \membersection{wxDC::SetMapMode}\label{wxdcsetmapmode} |
| 908 | |
| 909 | \func{void}{SetMapMode}{\param{int}{ int}} |
| 910 | |
| 911 | The {\it mapping mode} of the device context defines the unit of |
| 912 | measurement used to convert logical units to device units. Note that |
| 913 | in X, text drawing isn't handled consistently with the mapping mode; a |
| 914 | font is always specified in point size. However, setting the {\it |
| 915 | user scale} (see \helpref{wxDC::SetUserScale}{wxdcsetuserscale}) scales the text appropriately. In |
| 916 | Windows, scalable TrueType fonts are always used; in X, results depend |
| 917 | on availability of fonts, but usually a reasonable match is found. |
| 918 | |
| 919 | Note that the coordinate origin should ideally be selectable, but for |
| 920 | now is always at the top left of the screen/printer. |
| 921 | |
| 922 | Drawing to a Windows printer device context under UNIX |
| 923 | uses the current mapping mode, but mapping mode is currently ignored for |
| 924 | PostScript output. |
| 925 | |
| 926 | The mapping mode can be one of the following: |
| 927 | |
| 928 | \begin{twocollist}\itemsep=0pt |
| 929 | \twocolitem{wxMM\_TWIPS}{Each logical unit is 1/20 of a point, or 1/1440 of |
| 930 | an inch.} |
| 931 | \twocolitem{wxMM\_POINTS}{Each logical unit is a point, or 1/72 of an inch.} |
| 932 | \twocolitem{wxMM\_METRIC}{Each logical unit is 1 mm.} |
| 933 | \twocolitem{wxMM\_LOMETRIC}{Each logical unit is 1/10 of a mm.} |
| 934 | \twocolitem{wxMM\_TEXT}{Each logical unit is 1 pixel.} |
| 935 | \end{twocollist} |
| 936 | |
| 937 | \membersection{wxDC::SetOptimization}\label{wxsetoptimization} |
| 938 | |
| 939 | \func{void}{SetOptimization}{\param{bool }{optimize}} |
| 940 | |
| 941 | If {\it optimize} is TRUE (the default), this function sets optimization mode on. |
| 942 | This currently means that under X, the device context will not try to set a pen or brush |
| 943 | property if it is known to be set already. This approach can fall down |
| 944 | if non-wxWindows code is using the same device context or window, for example |
| 945 | when the window is a panel on which the windowing system draws panel items. |
| 946 | The wxWindows device context 'memory' will now be out of step with reality. |
| 947 | |
| 948 | Setting optimization off, drawing, then setting it back on again, is a trick |
| 949 | that must occasionally be employed. |
| 950 | |
| 951 | \membersection{wxDC::SetPen}\label{wxdcsetpen} |
| 952 | |
| 953 | \func{void}{SetPen}{\param{const wxPen\& }{pen}} |
| 954 | |
| 955 | Sets the current pen for the DC. |
| 956 | |
| 957 | If the argument is wxNullPen, the current pen is selected out of the device |
| 958 | context, and the original pen restored. |
| 959 | |
| 960 | See also \helpref{wxMemoryDC}{wxmemorydc} for the interpretation of colours |
| 961 | when drawing into a monochrome bitmap. |
| 962 | |
| 963 | \membersection{wxDC::SetTextBackground}\label{wxdcsettextbackground} |
| 964 | |
| 965 | \func{void}{SetTextBackground}{\param{const wxColour\& }{colour}} |
| 966 | |
| 967 | Sets the current text background colour for the DC. |
| 968 | |
| 969 | \membersection{wxDC::SetTextForeground}\label{wxdcsettextforeground} |
| 970 | |
| 971 | \func{void}{SetTextForeground}{\param{const wxColour\& }{colour}} |
| 972 | |
| 973 | Sets the current text foreground colour for the DC. |
| 974 | |
| 975 | See also \helpref{wxMemoryDC}{wxmemorydc} for the interpretation of colours |
| 976 | when drawing into a monochrome bitmap. |
| 977 | |
| 978 | \membersection{wxDC::SetUserScale}\label{wxdcsetuserscale} |
| 979 | |
| 980 | \func{void}{SetUserScale}{\param{double}{ xScale}, \param{double}{ yScale}} |
| 981 | |
| 982 | Sets the user scaling factor, useful for applications which require |
| 983 | `zooming'. |
| 984 | |
| 985 | \membersection{wxDC::StartDoc}\label{wxdcstartdoc} |
| 986 | |
| 987 | \func{bool}{StartDoc}{\param{const wxString\& }{message}} |
| 988 | |
| 989 | Starts a document (only relevant when outputting to a printer). |
| 990 | Message is a message to show whilst printing. |
| 991 | |
| 992 | \membersection{wxDC::StartPage}\label{wxdcstartpage} |
| 993 | |
| 994 | \func{bool}{StartPage}{\void} |
| 995 | |
| 996 | Starts a document page (only relevant when outputting to a printer). |
| 997 | |
| 998 | \section{\class{wxDCClipper}}\label{wxdcclipper} |
| 999 | |
| 1000 | This is a small helper class which sets the specified to its constructor |
| 1001 | clipping region and then automatically destroys it in its destructor. Using |
| 1002 | it ensures that unwanted clipping region is not left set on the DC. |
| 1003 | |
| 1004 | \wxheading{Derived from} |
| 1005 | |
| 1006 | No base class |
| 1007 | |
| 1008 | \wxheading{Include files} |
| 1009 | |
| 1010 | <wx/dc.h> |
| 1011 | |
| 1012 | \wxheading{See also} |
| 1013 | |
| 1014 | \helpref{wxDC}{wxdc} |
| 1015 | |
| 1016 | \latexignore{\rtfignore{\wxheading{Members}}} |
| 1017 | |
| 1018 | \membersection{wxDCClipper::wxDCClipper} |
| 1019 | |
| 1020 | \func{}{wxDCClipper}{\param{wxDC\& }{dc}, \param{wxCoord }{x},\param{wxCoord }{y},\param{wxCoord }{w},\param{wxCoord }{h},} |
| 1021 | |
| 1022 | \func{}{wxDCClipper}{\param{wxDC\& }{dc}, \param{const wxRect\&}{ rect}} |
| 1023 | |
| 1024 | Constructor: sets the the clipping region for the given device context to the |
| 1025 | specified rectangle. |
| 1026 | |
| 1027 | \membersection{wxDCClipper::\destruct{wxDCClipper}} |
| 1028 | |
| 1029 | \func{}{\destruct{wxDCClipper}}{\void} |
| 1030 | |
| 1031 | Destructor: destroys the clipping region set in the constructor. |
| 1032 | |