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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 Notice that wxDC is an abstract base class and can't be created directly,
10 please use \helpref{wxPaintDC}{wxpaintdc}, \helpref{wxClientDC}{wxclientdc},
11 \helpref{wxWindowDC}{wxwindowdc}, \helpref{wxScreenDC}{wxscreendc},
12 \helpref{wxMemoryDC}{wxmemorydc} or \helpref{wxPrinterDC}{wxprinterdc}.
13
14 % VZ: we should really document them instead of this lame excuse, but I don't
15 % have time for it now, when it is done please remove this
16 Please note that in addition to the versions of the methods documented here,
17 there are also versions which accept single {\tt wxPoint} parameter instead of
18 two {\tt wxCoord} ones or {\tt wxPoint} and {\tt wxSize} instead of four of
19 them.
20
21 \wxheading{Support for Transparency / Alpha Channel}
22
23 On Mac OS X when using Core Graphics (wx\_MAC\_USE\_CORE\_GRAPHICS set to 1)
24 colors with alpha are supported, so instances {\tt wxPen} or {\tt wxBrush} that are built from {\tt wxColour} use
25 the color's alpha values when stroking or filling.
26
27 \wxheading{Derived from}
28
29 \helpref{wxObject}{wxobject}
30
31 \wxheading{Include files}
32
33 <wx/dc.h>
34
35 \wxheading{Library}
36
37 \helpref{wxCore}{librarieslist}
38
39 \wxheading{See also}
40
41 \helpref{Overview}{dcoverview}
42
43 \latexignore{\rtfignore{\wxheading{Members}}}
44
45
46 \membersection{wxDC::Blit}\label{wxdcblit}
47
48 \func{bool}{Blit}{\param{wxCoord}{ xdest}, \param{wxCoord}{ ydest}, \param{wxCoord}{ width}, \param{wxCoord}{ height},
49 \param{wxDC* }{source}, \param{wxCoord}{ xsrc}, \param{wxCoord}{ ysrc}, \param{int}{ logicalFunc = wxCOPY},
50 \param{bool }{useMask = false}, \param{wxCoord}{ xsrcMask = -1}, \param{wxCoord}{ ysrcMask = -1}}
51
52 Copy from a source DC to this DC, specifying the destination
53 coordinates, size of area to copy, source DC, source coordinates,
54 logical function, whether to use a bitmap mask, and mask source position.
55
56 \wxheading{Parameters}
57
58 \docparam{xdest}{Destination device context x position.}
59
60 \docparam{ydest}{Destination device context y position.}
61
62 \docparam{width}{Width of source area to be copied.}
63
64 \docparam{height}{Height of source area to be copied.}
65
66 \docparam{source}{Source device context.}
67
68 \docparam{xsrc}{Source device context x position.}
69
70 \docparam{ysrc}{Source device context y position.}
71
72 \docparam{logicalFunc}{Logical function to use: see \helpref{wxDC::SetLogicalFunction}{wxdcsetlogicalfunction}.}
73
74 \docparam{useMask}{If true, Blit does a transparent blit using the mask that is associated with the bitmap
75 selected into the source device context. The Windows implementation does the following if MaskBlt cannot be used:
76
77 \begin{enumerate}
78 \item Creates a temporary bitmap and copies the destination area into it.
79 \item Copies the source area into the temporary bitmap using the specified logical function.
80 \item Sets the masked area in the temporary bitmap to BLACK by ANDing the
81 mask bitmap with the temp bitmap with the foreground colour set to WHITE
82 and the bg colour set to BLACK.
83 \item Sets the unmasked area in the destination area to BLACK by ANDing the
84 mask bitmap with the destination area with the foreground colour set to BLACK
85 and the background colour set to WHITE.
86 \item ORs the temporary bitmap with the destination area.
87 \item Deletes the temporary bitmap.
88 \end{enumerate}
89
90 This sequence of operations ensures that the source's transparent area need not be black,
91 and logical functions are supported.
92
93 {\bf Note:} on Windows, blitting with masks can be speeded up considerably by compiling
94 wxWidgets with the wxUSE\_DC\_CACHE option enabled. You can also influence whether MaskBlt
95 or the explicit mask blitting code above is used, by using \helpref{wxSystemOptions}{wxsystemoptions} and
96 setting the {\bf no-maskblt} option to 1.
97
98 }
99
100 \docparam{xsrcMask}{Source x position on the mask. If both xsrcMask and ysrcMask are -1, xsrc and ysrc
101 will be assumed for the mask source position. Currently only implemented on Windows.}
102
103 \docparam{ysrcMask}{Source y position on the mask. If both xsrcMask and ysrcMask are -1, xsrc and ysrc
104 will be assumed for the mask source position. Currently only implemented on Windows.}
105
106
107 \wxheading{Remarks}
108
109 There is partial support for Blit in wxPostScriptDC, under X.
110
111 See \helpref{wxMemoryDC}{wxmemorydc} for typical usage.
112
113 \wxheading{See also}
114
115 \helpref{wxDC::StretchBlit}{wxdcstretchblit}, \helpref{wxMemoryDC}{wxmemorydc}, \helpref{wxBitmap}{wxbitmap}, \helpref{wxMask}{wxmask}
116
117 \begin{comment}
118
119 \membersection{wxDC::CacheEnabled}\label{wxdccacheenabled}
120
121 \func{static bool}{CacheEnabled}{\void}
122
123 On supported platforms (currently only Windows), returns true
124 if the DC cache is enabled. The DC cache
125 can speed up the \helpref{Blit}{wxdcblit} operation when
126 drawing a large number of masked bitmaps.
127
128 If using the cache functions in your code, please test for the
129 wxUSE\_DC\_CACHEING preprocessor symbol for portability.
130
131 \wxheading{See also}
132
133 \helpref{wxDC::EnableCache}{wxdcenablecache}, \helpref{wxDC::ClearCache}
134 \end{comment}
135
136
137 \membersection{wxDC::CalcBoundingBox}\label{wxdccalcboundingbox}
138
139 \func{void}{CalcBoundingBox}{\param{wxCoord }{x}, \param{wxCoord }{y}}
140
141 Adds the specified point to the bounding box which can be retrieved with
142 \helpref{MinX}{wxdcminx}, \helpref{MaxX}{wxdcmaxx} and
143 \helpref{MinY}{wxdcminy}, \helpref{MaxY}{wxdcmaxy} functions.
144
145 \wxheading{See also}
146
147 \helpref{ResetBoundingBox}{wxdcresetboundingbox}
148
149
150 \membersection{wxDC::Clear}\label{wxdcclear}
151
152 \func{void}{Clear}{\void}
153
154 Clears the device context using the current background brush.
155
156 \begin{comment}
157
158 \membersection{wxDC::ClearCache}\label{wxdcclearcache}
159
160 \func{static void}{ClearCache}{\void}
161
162 On supported platforms (currently only Windows), clears
163 the contents of the DC cache (one bitmap and two Windows device contexts). The DC cache
164 can speed up the \helpref{Blit}{wxdcblit} operation when
165 drawing a large number of masked bitmaps. You should
166 call ClearCache at the end of length DC operations if you wish to only use
167 the cache transiently; you should also call it as your application exits.
168
169 If using the cache functions in your code, please test for the
170 wxUSE\_DC\_CACHEING preprocessor symbol for portability.
171
172 \wxheading{See also}
173
174 \helpref{wxDC::EnableCache}{wxdcenablecache}, \helpref{wxDC::CacheEnabled}
175 \end{comment}
176
177
178 \membersection{wxDC::ComputeScaleAndOrigin}\label{wxdccomputescaleandorigin}
179
180 \func{virtual void}{ComputeScaleAndOrigin}{\void}
181
182 Performs all necessary computations for given platform and context type
183 after each change of scale and origin parameters. Usually called automatically
184 internally after such changes.
185
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
196 \membersection{wxDC::DestroyClippingRegion}\label{wxdcdestroyclippingregion}
197
198 \func{void}{DestroyClippingRegion}{\void}
199
200 Destroys the current clipping region so that none of the DC is clipped.
201 See also \helpref{wxDC::SetClippingRegion}{wxdcsetclippingregion}.
202
203
204 \membersection{wxDC::DeviceToLogicalX}\label{wxdcdevicetologicalx}
205
206 \func{virtual wxCoord}{DeviceToLogicalX}{\param{wxCoord}{ x}}
207
208 Convert device X coordinate to logical coordinate, using the current
209 mapping mode.
210
211
212 \membersection{wxDC::DeviceToLogicalXRel}\label{wxdcdevicetologicalxrel}
213
214 \func{virtual wxCoord}{DeviceToLogicalXRel}{\param{wxCoord}{ x}}
215
216 Convert device X coordinate to relative logical coordinate, using the current
217 mapping mode but ignoring the x axis orientation.
218 Use this function for converting a width, for example.
219
220
221 \membersection{wxDC::DeviceToLogicalY}\label{wxdcdevicetologicaly}
222
223 \func{virtual wxCoord}{DeviceToLogicalY}{\param{wxCoord}{ y}}
224
225 Converts device Y coordinate to logical coordinate, using the current
226 mapping mode.
227
228
229 \membersection{wxDC::DeviceToLogicalYRel}\label{wxdcdevicetologicalyrel}
230
231 \func{virtual wxCoord}{DeviceToLogicalYRel}{\param{wxCoord}{ y}}
232
233 Convert device Y coordinate to relative logical coordinate, using the current
234 mapping mode but ignoring the y axis orientation.
235 Use this function for converting a height, for example.
236
237
238 \membersection{wxDC::DrawArc}\label{wxdcdrawarc}
239
240 \func{void}{DrawArc}{\param{wxCoord}{ x1}, \param{wxCoord}{ y1}, \param{wxCoord}{ x2}, \param{wxCoord}{ y2}, \param{wxCoord}{ xc}, \param{wxCoord}{ yc}}
241
242 Draws an arc of a circle, centred on ({\it xc, yc}), with starting point ({\it x1, y1})
243 and ending at ({\it x2, y2}). The current pen is used for the outline
244 and the current brush for filling the shape.
245
246 The arc is drawn in an anticlockwise direction from the start point to the end point.
247
248
249 \membersection{wxDC::DrawBitmap}\label{wxdcdrawbitmap}
250
251 \func{void}{DrawBitmap}{\param{const wxBitmap\&}{ bitmap}, \param{wxCoord}{ x}, \param{wxCoord}{ y}, \param{bool}{ transparent}}
252
253 Draw a bitmap on the device context at the specified point. If {\it transparent} is true and the bitmap has
254 a transparency mask, the bitmap will be drawn transparently.
255
256 When drawing a mono-bitmap, the current text foreground colour will be used to draw the foreground
257 of the bitmap (all bits set to 1), and the current text background colour to draw the background
258 (all bits set to 0). See also \helpref{SetTextForeground}{wxdcsettextforeground},
259 \helpref{SetTextBackground}{wxdcsettextbackground} and \helpref{wxMemoryDC}{wxmemorydc}.
260
261
262 \membersection{wxDC::DrawCheckMark}\label{wxdcdrawcheckmark}
263
264 \func{void}{DrawCheckMark}{\param{wxCoord}{ x}, \param{wxCoord}{ y}, \param{wxCoord}{ width}, \param{wxCoord}{ height}}
265
266 \func{void}{DrawCheckMark}{\param{const wxRect \&}{rect}}
267
268 Draws a check mark inside the given rectangle.
269
270
271 \membersection{wxDC::DrawCircle}\label{wxdcdrawcircle}
272
273 \func{void}{DrawCircle}{\param{wxCoord}{ x}, \param{wxCoord}{ y}, \param{wxCoord}{ radius}}
274
275 \func{void}{DrawCircle}{\param{const wxPoint\&}{ pt}, \param{wxCoord}{ radius}}
276
277 Draws a circle with the given centre and radius.
278
279 \wxheading{See also}
280
281 \helpref{DrawEllipse}{wxdcdrawellipse}
282
283
284 \membersection{wxDC::DrawEllipse}\label{wxdcdrawellipse}
285
286 \func{void}{DrawEllipse}{\param{wxCoord}{ x}, \param{wxCoord}{ y}, \param{wxCoord}{ width}, \param{wxCoord}{ height}}
287
288 \func{void}{DrawEllipse}{\param{const wxPoint\&}{ pt}, \param{const wxSize\&}{ size}}
289
290 \func{void}{DrawEllipse}{\param{const wxRect\&}{ rect}}
291
292 Draws an ellipse contained in the rectangle specified either with the given top
293 left corner and the given size or directly. The current pen is used for the
294 outline and the current brush for filling the shape.
295
296 \wxheading{See also}
297
298 \helpref{DrawCircle}{wxdcdrawcircle}
299
300
301 \membersection{wxDC::DrawEllipticArc}\label{wxdcdrawellipticarc}
302
303 \func{void}{DrawEllipticArc}{\param{wxCoord}{ x}, \param{wxCoord}{ y}, \param{wxCoord}{ width}, \param{wxCoord}{ height},
304 \param{double}{ start}, \param{double}{ end}}
305
306 Draws an arc of an ellipse. The current pen is used for drawing the arc and
307 the current brush is used for drawing the pie.
308
309 {\it x} and {\it y} specify the x and y coordinates of the upper-left corner of the rectangle that contains
310 the ellipse.
311
312 {\it width} and {\it height} specify the width and height of the rectangle that contains
313 the ellipse.
314
315 {\it start} and {\it end} specify the start and end of the arc relative to the three-o'clock
316 position from the center of the rectangle. Angles are specified
317 in degrees (360 is a complete circle). Positive values mean
318 counter-clockwise motion. If {\it start} is equal to {\it end}, a
319 complete ellipse will be drawn.
320
321
322 \membersection{wxDC::DrawIcon}\label{wxdcdrawicon}
323
324 \func{void}{DrawIcon}{\param{const wxIcon\&}{ icon}, \param{wxCoord}{ x}, \param{wxCoord}{ y}}
325
326 Draw an icon on the display (does nothing if the device context is PostScript).
327 This can be the simplest way of drawing bitmaps on a window.
328
329
330 \membersection{wxDC::DrawLabel}\label{wxdcdrawlabel}
331
332 \func{virtual void}{DrawLabel}{\param{const wxString\&}{ text},
333 \param{const wxBitmap\&}{ image},
334 \param{const wxRect\&}{ rect},
335 \param{int}{ alignment = wxALIGN\_LEFT | wxALIGN\_TOP},
336 \param{int}{ indexAccel = -1},
337 \param{wxRect *}{rectBounding = NULL}}
338
339 \func{void}{DrawLabel}{\param{const wxString\&}{ text}, \param{const wxRect\&}{ rect},
340 \param{int}{ alignment = wxALIGN\_LEFT | wxALIGN\_TOP},
341 \param{int}{ indexAccel = -1}}
342
343 Draw optional bitmap and the text into the given rectangle and aligns it as specified
344 by alignment parameter; it also will emphasize the character with the given index if
345 it is != -1 and return the bounding rectangle if required.
346
347
348 \membersection{wxDC::DrawLine}\label{wxdcdrawline}
349
350 \func{void}{DrawLine}{\param{wxCoord}{ x1}, \param{wxCoord}{ y1}, \param{wxCoord}{ x2}, \param{wxCoord}{ y2}}
351
352 Draws a line from the first point to the second. The current pen is used
353 for drawing the line. Note that the point $(x2, y2)$ is {\emph not} part of the
354 line and is not drawn by this function (this is consistent with the behaviour
355 of many other toolkits).
356
357
358 \membersection{wxDC::DrawLines}\label{wxdcdrawlines}
359
360 \func{void}{DrawLines}{\param{int}{ n}, \param{wxPoint}{ points[]}, \param{wxCoord}{ xoffset = 0}, \param{wxCoord}{ yoffset = 0}}
361
362 Draws lines using an array of {\it points} of size {\it n}
363 adding the optional offset coordinate. The current pen is
364 used for drawing the lines.
365
366 \func{void}{DrawLines}{\param{const wxPointList *}{points}, \param{wxCoord}{ xoffset = 0}, \param{wxCoord}{ yoffset = 0}}
367
368 This method uses a list of wxPoints, adding the optional offset
369 coordinate. The programmer is responsible for deleting the list
370 of points.
371
372 \pythonnote{The wxPython version of this method accepts a Python list
373 of wxPoint objects.}
374
375 \perlnote{The wxPerl version of this method accepts
376 as its first parameter a reference to an array
377 of wxPoint objects.}
378
379
380 \membersection{wxDC::DrawPolygon}\label{wxdcdrawpolygon}
381
382 \func{void}{DrawPolygon}{\param{int}{ n}, \param{wxPoint}{ points[]}, \param{wxCoord}{ xoffset = 0}, \param{wxCoord}{ yoffset = 0},\\
383 \param{int }{fill\_style = wxODDEVEN\_RULE}}
384
385 Draws a filled polygon using an array of {\it points} of size {\it n},
386 adding the optional offset coordinate.
387
388 \func{void}{DrawPolygon}{\param{const wxPointList *}{points}, \param{wxCoord}{ xoffset = 0}, \param{wxCoord}{ yoffset = 0},\\
389 \param{int }{fill\_style = wxODDEVEN\_RULE}}
390
391 This method draws a filled polygon using a list of wxPoints,
392 adding the optional offset coordinate.
393
394 The last argument specifies the fill rule: {\bf wxODDEVEN\_RULE} (the
395 default) or {\bf wxWINDING\_RULE}.
396
397 The current pen is used for drawing the outline, and the current brush
398 for filling the shape. Using a transparent brush suppresses filling.
399 The programmer is responsible for deleting the list of points.
400
401 Note that wxWidgets automatically closes the first and last points.
402
403 \pythonnote{The wxPython version of this method accepts a Python list
404 of wxPoint objects.}
405
406 \perlnote{The wxPerl version of this method accepts
407 as its first parameter a reference to an array
408 of wxPoint objects.}
409
410
411 \membersection{wxDC::DrawPolyPolygon}\label{wxdcdrawpolypolygon}
412
413 \func{void}{DrawPolyPolygon}{\param{int}{ n}, \param{int}{ count[]}, \param{wxPoint}{ points[]}, \param{wxCoord}{ xoffset = 0}, \param{wxCoord}{ yoffset = 0},\\
414 \param{int }{fill\_style = wxODDEVEN\_RULE}}
415
416 Draws two or more filled polygons using an array of {\it points}, adding the
417 optional offset coordinates.
418
419 Notice that for the platforms providing a native implementation
420 of this function (Windows and PostScript-based wxDC currently), this is more
421 efficient than using \helpref{DrawPolygon}{wxdcdrawpolygon} in a loop.
422
423 {\it n} specifies the number of polygons to draw, the array {\it count} of size
424 {\it n} specifies the number of points in each of the polygons in the
425 {\it points} array.
426
427 The last argument specifies the fill rule: {\bf wxODDEVEN\_RULE} (the default)
428 or {\bf wxWINDING\_RULE}.
429
430 The current pen is used for drawing the outline, and the current brush for
431 filling the shape. Using a transparent brush suppresses filling.
432
433 The polygons maybe disjoint or overlapping. Each polygon specified in a call to
434 {\bf DrawPolyPolygon} must be closed. Unlike polygons created by the
435 \helpref{DrawPolygon}{wxdcdrawpolygon} member function, the polygons created by
436 {\bf DrawPolyPolygon} are not closed automatically.
437
438 \pythonnote{Not implemented yet}
439
440 \perlnote{Not implemented yet}
441
442
443 \membersection{wxDC::DrawPoint}\label{wxdcdrawpoint}
444
445 \func{void}{DrawPoint}{\param{wxCoord}{ x}, \param{wxCoord}{ y}}
446
447 Draws a point using the color of the current pen. Note that the other properties of the pen are not used, such as width etc..
448
449
450 \membersection{wxDC::DrawRectangle}\label{wxdcdrawrectangle}
451
452 \func{void}{DrawRectangle}{\param{wxCoord}{ x}, \param{wxCoord}{ y}, \param{wxCoord}{ width}, \param{wxCoord}{ height}}
453
454 Draws a rectangle with the given top left corner, and with the given
455 size. The current pen is used for the outline and the current brush
456 for filling the shape.
457
458
459 \membersection{wxDC::DrawRotatedText}\label{wxdcdrawrotatedtext}
460
461 \func{void}{DrawRotatedText}{\param{const wxString\& }{text}, \param{wxCoord}{ x}, \param{wxCoord}{ y}, \param{double}{ angle}}
462
463 Draws the text rotated by {\it angle} degrees.
464
465 {\bf NB:} Under Win9x only TrueType fonts can be drawn by this function. In
466 particular, a font different from {\tt wxNORMAL\_FONT} should be used as the
467 latter is not a TrueType font. {\tt wxSWISS\_FONT} is an example of a font
468 which is.
469
470 \wxheading{See also}
471
472 \helpref{DrawText}{wxdcdrawtext}
473
474
475 \membersection{wxDC::DrawRoundedRectangle}\label{wxdcdrawroundedrectangle}
476
477 \func{void}{DrawRoundedRectangle}{\param{wxCoord}{ x}, \param{wxCoord}{ y}, \param{wxCoord}{ width}, \param{wxCoord}{ height}, \param{double}{ radius}}
478
479 Draws a rectangle with the given top left corner, and with the given
480 size. The corners are quarter-circles using the given radius. The
481 current pen is used for the outline and the current brush for filling
482 the shape.
483
484 If {\it radius} is positive, the value is assumed to be the
485 radius of the rounded corner. If {\it radius} is negative,
486 the absolute value is assumed to be the {\it proportion} of the smallest
487 dimension of the rectangle. This means that the corner can be
488 a sensible size relative to the size of the rectangle, and also avoids
489 the strange effects X produces when the corners are too big for
490 the rectangle.
491
492
493 \membersection{wxDC::DrawSpline}\label{wxdcdrawspline}
494
495 \func{void}{DrawSpline}{\param{int }{n}, \param{wxPoint }{points[]}}
496
497 Draws a spline between all given control points, using the current
498 pen.
499
500 \func{void}{DrawSpline}{\param{const wxPointList *}{points}}
501
502 Draws a spline between all given control points.
503
504 \func{void}{DrawSpline}{\param{wxCoord}{ x1}, \param{wxCoord}{ y1}, \param{wxCoord}{ x2}, \param{wxCoord}{ y2}, \param{wxCoord}{ x3}, \param{wxCoord}{ y3}}
505
506 Draws a three-point spline using the current pen.
507
508 \pythonnote{The wxPython version of this method accepts a Python list
509 of wxPoint objects.}
510
511 \perlnote{The wxPerl version of this method accepts a reference to an array
512 of wxPoint objects.}
513
514
515 \membersection{wxDC::DrawText}\label{wxdcdrawtext}
516
517 \func{void}{DrawText}{\param{const wxString\& }{text}, \param{wxCoord}{ x}, \param{wxCoord}{ y}}
518
519 Draws a text string at the specified point, using the current text font,
520 and the current text foreground and background colours.
521
522 The coordinates refer to the top-left corner of the rectangle bounding
523 the string. See \helpref{wxDC::GetTextExtent}{wxdcgettextextent} for how
524 to get the dimensions of a text string, which can be used to position the
525 text more precisely.
526
527 {\bf NB:} under wxGTK the current
528 \helpref{logical function}{wxdcgetlogicalfunction} is used by this function
529 but it is ignored by wxMSW. Thus, you should avoid using logical functions
530 with this function in portable programs.
531
532 \begin{comment}
533
534 \membersection{wxDC::EnableCache}\label{wxdcenablecache}
535
536 \func{static void}{EnableCache}{\param{bool}{ enableCache}}
537
538 On supported platforms (currently only Windows), enables the DC cache
539 which can speed up the \helpref{Blit}{wxdcblit} operation when
540 drawing a large number of masked bitmaps.
541
542 If using the cache functions in your code, please test for the
543 wxUSE\_DC\_CACHEING preprocessor symbol for portability.
544
545 \wxheading{See also}
546
547 \helpref{wxDC::CacheEnabled}{wxdccacheenabled}, \helpref{wxDC::ClearCache}
548 \end{comment}
549
550
551 \membersection{wxDC::EndDoc}\label{wxdcenddoc}
552
553 \func{void}{EndDoc}{\void}
554
555 Ends a document (only relevant when outputting to a printer).
556
557
558 \membersection{wxDC::EndPage}\label{wxdcendpage}
559
560 \func{void}{EndPage}{\void}
561
562 Ends a document page (only relevant when outputting to a printer).
563
564
565 \membersection{wxDC::FloodFill}\label{wxdcfloodfill}
566
567 \func{bool}{FloodFill}{\param{wxCoord}{ x}, \param{wxCoord}{ y}, \param{const wxColour\&}{ colour}, \param{int}{ style=wxFLOOD\_SURFACE}}
568
569 Flood fills the device context starting from the given point, using
570 the {\it current brush colour}, and using a style:
571
572 \begin{itemize}\itemsep=0pt
573 \item wxFLOOD\_SURFACE: the flooding occurs until a colour other than the given colour is encountered.
574 \item wxFLOOD\_BORDER: the area to be flooded is bounded by the given colour.
575 \end{itemize}
576
577 Returns false if the operation failed.
578
579 {\it Note:} The present implementation for non-Windows platforms may fail to find
580 colour borders if the pixels do not match the colour exactly. However the
581 function will still return true.
582
583
584 \membersection{wxDC::GetBackground}\label{wxdcgetbackground}
585
586 \constfunc{const wxBrush\&}{GetBackground}{\void}
587
588 Gets the brush used for painting the background (see \helpref{wxDC::SetBackground}{wxdcsetbackground}).
589
590
591 \membersection{wxDC::GetBackgroundMode}\label{wxdcgetbackgroundmode}
592
593 \constfunc{int}{GetBackgroundMode}{\void}
594
595 Returns the current background mode: {\tt wxSOLID} or {\tt wxTRANSPARENT}.
596
597 \wxheading{See also}
598
599 \helpref{SetBackgroundMode}{wxdcsetbackgroundmode}
600
601
602 \membersection{wxDC::GetBrush}\label{wxdcgetbrush}
603
604 \constfunc{const wxBrush\&}{GetBrush}{\void}
605
606 Gets the current brush (see \helpref{wxDC::SetBrush}{wxdcsetbrush}).
607
608
609 \membersection{wxDC::GetCharHeight}\label{wxdcgetcharheight}
610
611 \func{wxCoord}{GetCharHeight}{\void}
612
613 Gets the character height of the currently set font.
614
615
616 \membersection{wxDC::GetCharWidth}\label{wxdcgetcharwidth}
617
618 \func{wxCoord}{GetCharWidth}{\void}
619
620 Gets the average character width of the currently set font.
621
622
623 \membersection{wxDC::GetClippingBox}\label{wxdcgetclippingbox}
624
625 \func{void}{GetClippingBox}{\param{wxCoord}{ *x}, \param{wxCoord}{ *y}, \param{wxCoord}{ *width}, \param{wxCoord}{ *height}}
626
627 Gets the rectangle surrounding the current clipping region.
628
629 \pythonnote{No arguments are required and the four values defining the
630 rectangle are returned as a tuple.}
631
632 \perlnote{This method takes no arguments and returns a four element list
633 {\tt ( x, y, width, height )}}
634
635
636 \membersection{wxDC::GetDepth}\label{wxdcgetdepth}
637
638 \constfunc{int}{GetDepth}{\void}
639
640 Returns the depth (number of bits/pixel) of this DC.
641
642 \wxheading{See also}
643
644 \helpref{wxDisplayDepth}{wxdisplaydepth}
645
646
647 \membersection{wxDC::GetFont}\label{wxdcgetfont}
648
649 \constfunc{const wxFont\&}{GetFont}{\void}
650
651 Gets the current font. Notice that even although each device context object has
652 some default font after creation, this method would return a \texttt{wxNullFont}
653 initially and only after calling \helpref{wxDC::SetFont}{wxdcsetfont} a valid
654 font is returned.
655
656
657 \membersection{wxDC::GetLayoutDirection}\label{wxdcgetlayoutdirection}
658
659 \constfunc{wxLayoutDirection}{GetLayoutDirection}{\void}
660
661 Gets the current layout direction of the device context. On platforms where RTL layout
662 is supported, the return value will either be \texttt{wxLayout\_LeftToRight} or
663 \texttt{wxLayout\_RightToLeft}. If RTL layout is not supported, the return value will
664 be \texttt{wxLayout\_Default}.
665
666 \wxheading{See also}
667
668 \helpref{SetLayoutDirection}{wxdcsetlayoutdirection}
669
670
671 \membersection{wxDC::GetLogicalFunction}\label{wxdcgetlogicalfunction}
672
673 \func{int}{GetLogicalFunction}{\void}
674
675 Gets the current logical function (see \helpref{wxDC::SetLogicalFunction}{wxdcsetlogicalfunction}).
676
677
678 \membersection{wxDC::GetMapMode}\label{wxdcgetmapmode}
679
680 \func{int}{GetMapMode}{\void}
681
682 Gets the {\it mapping mode} for the device context (see \helpref{wxDC::SetMapMode}{wxdcsetmapmode}).
683
684
685 \membersection{wxDC::GetMultiLineTextExtent}\label{wxdcgetmultilinetextextent}
686
687 \constfunc{void}{GetMultiLineTextExtent}{\param{const wxString\& }{string}, \param{wxCoord *}{w},\\
688 \param{wxCoord *}{h}, \param{wxCoord *}{heightLine = NULL}, \param{wxFont *}{font = NULL}}
689
690 \constfunc{wxSize}{GetMultiLineTextExtent}{\param{const wxString\& }{string}}
691
692 Gets the dimensions of the string using the currently selected font.
693 \rtfsp{\it string} is the text string to measure, {\it heightLine}, if non NULL,
694 is where to store the height of a single line.
695
696 The text extent is returned in {\it w} and {\it h} pointers (first form) or as
697 a \helpref{wxSize}{wxsize} object (second form).
698
699 If the optional parameter {\it font} is specified and valid, then it is used
700 for the text extent calculation. Otherwise the currently selected font is.
701
702 Note that this function works both with single-line and multi-line strings.
703
704 \wxheading{See also}
705
706 \helpref{wxFont}{wxfont},\rtfsp
707 \helpref{wxDC::SetFont}{wxdcsetfont},\rtfsp
708 \helpref{wxDC::GetPartialTextExtents}{wxdcgetpartialtextextents},\rtfsp
709 \helpref{wxDC::GetTextExtent}{wxdcgettextextent}
710
711
712 \membersection{wxDC::GetPartialTextExtents}\label{wxdcgetpartialtextextents}
713
714 \constfunc{bool}{GetPartialTextExtents}{\param{const wxString\& }{text},
715 \param{wxArrayInt\& }{widths}}
716
717 Fills the {\it widths} array with the widths from the beginning of
718 {\it text} to the corresponding character of {\it text}. The generic
719 version simply builds a running total of the widths of each character
720 using \helpref{GetTextExtent}{wxdcgettextextent}, however if the
721 various platforms have a native API function that is faster or more
722 accurate than the generic implementation then it should be used
723 instead.
724
725 \wxheading{See also}
726
727 \helpref{wxDC::GetMultiLineTextExtent}{wxdcgetmultilinetextextent},\rtfsp
728 \helpref{wxDC::GetTextExtent}{wxdcgettextextent}
729
730 \pythonnote{This method only takes the {\it text} parameter and
731 returns a Python list of integers.}
732
733
734 \membersection{wxDC::GetPen}\label{wxdcgetpen}
735
736 \constfunc{const wxPen\&}{GetPen}{\void}
737
738 Gets the current pen (see \helpref{wxDC::SetPen}{wxdcsetpen}).
739
740
741 \membersection{wxDC::GetPixel}\label{wxdcgetpixel}
742
743 \func{bool}{GetPixel}{\param{wxCoord}{ x}, \param{wxCoord}{ y}, \param{wxColour *}{colour}}
744
745 Gets in {\it colour} the colour at the specified location.
746 Not available for wxPostScriptDC or wxMetafileDC.
747
748 Note that setting a pixel can be done using \helpref{DrawPoint}{wxdcdrawpoint}.
749
750 \pythonnote{For wxPython the wxColour value is returned and is not
751 required as a parameter.}
752
753 \perlnote{This method only takes the parameters {\tt x} and {\tt y} and returns
754 a Wx::Colour value}
755
756 \membersection{wxDC::GetPPI}\label{wxdcgetppi}
757
758 \constfunc{wxSize}{GetPPI}{\void}
759
760 Returns the resolution of the device in pixels per inch.
761
762 \membersection{wxDC::GetSize}\label{wxdcgetsize}
763
764 \constfunc{void}{GetSize}{\param{wxCoord *}{width}, \param{wxCoord *}{height}}
765
766 \constfunc{wxSize}{GetSize}{\void}
767
768 This gets the horizontal and vertical resolution in device units. It can be used to scale graphics to fit the page.
769 For example, if {\it maxX} and {\it maxY}\rtfsp
770 represent the maximum horizontal and vertical `pixel' values used in your
771 application, the following code will scale the graphic to fit on the
772 printer page:
773
774 \begin{verbatim}
775 wxCoord w, h;
776 dc.GetSize(&w, &h);
777 double scaleX=(double)(maxX/w);
778 double scaleY=(double)(maxY/h);
779 dc.SetUserScale(min(scaleX,scaleY),min(scaleX,scaleY));
780 \end{verbatim}
781
782 \pythonnote{In place of a single overloaded method name, wxPython
783 implements the following methods:\par
784 \indented{2cm}{\begin{twocollist}
785 \twocolitem{{\bf GetSize()}}{Returns a wxSize}
786 \twocolitem{{\bf GetSizeTuple()}}{Returns a 2-tuple (width, height)}
787 \end{twocollist}}
788 }
789
790 \perlnote{In place of a single overloaded method, wxPerl uses:\par
791 \indented{2cm}{\begin{twocollist}
792 \twocolitem{{\bf GetSize()}}{Returns a Wx::Size}
793 \twocolitem{{\bf GetSizeWH()}}{Returns a 2-element list
794 {\tt ( width, height )}}
795 \end{twocollist}
796 }}
797
798 \membersection{wxDC::GetSizeMM}\label{wxdcgetsizemm}
799
800 \constfunc{void}{GetSizeMM}{\param{wxCoord *}{width}, \param{wxCoord *}{height}}
801
802 \constfunc{wxSize}{GetSizeMM}{\void}
803
804 Returns the horizontal and vertical resolution in millimetres.
805
806 \membersection{wxDC::GetTextBackground}\label{wxdcgettextbackground}
807
808 \constfunc{const wxColour\&}{GetTextBackground}{\void}
809
810 Gets the current text background colour (see \helpref{wxDC::SetTextBackground}{wxdcsettextbackground}).
811
812
813 \membersection{wxDC::GetTextExtent}\label{wxdcgettextextent}
814
815 \constfunc{void}{GetTextExtent}{\param{const wxString\& }{string}, \param{wxCoord *}{w}, \param{wxCoord *}{h},\\
816 \param{wxCoord *}{descent = NULL}, \param{wxCoord *}{externalLeading = NULL}, \param{const wxFont *}{font = NULL}}
817
818 \constfunc{wxSize}{GetTextExtent}{\param{const wxString\& }{string}}
819
820 Gets the dimensions of the string using the currently selected font.
821 \rtfsp{\it string} is the text string to measure, {\it descent} is the
822 dimension from the baseline of the font to the bottom of the
823 descender, and {\it externalLeading} is any extra vertical space added
824 to the font by the font designer (usually is zero).
825
826 The text extent is returned in {\it w} and {\it h} pointers (first form) or as
827 a \helpref{wxSize}{wxsize} object (second form).
828
829 If the optional parameter {\it font} is specified and valid, then it is used
830 for the text extent calculation. Otherwise the currently selected font is.
831
832 Note that this function only works with single-line strings.
833
834 \wxheading{See also}
835
836 \helpref{wxFont}{wxfont},\rtfsp
837 \helpref{wxDC::SetFont}{wxdcsetfont},\rtfsp
838 \helpref{wxDC::GetPartialTextExtents}{wxdcgetpartialtextextents},\rtfsp
839 \helpref{wxDC::GetMultiLineTextExtent}{wxdcgetmultilinetextextent}
840
841 \pythonnote{The following methods are implemented in wxPython:\par
842 \indented{2cm}{\begin{twocollist}
843 \twocolitem{{\bf GetTextExtent(string)}}{Returns a 2-tuple, (width, height)}
844 \twocolitem{{\bf GetFullTextExtent(string, font=NULL)}}{Returns a
845 4-tuple, (width, height, descent, externalLeading) }
846 \end{twocollist}}
847 }
848
849 \perlnote{In wxPerl this method is implemented as
850 {\bf GetTextExtent( string, font = undef )} returning a four element
851 array {\tt ( width, height, descent, externalLeading )}
852 }
853
854
855 \membersection{wxDC::GetTextForeground}\label{wxdcgettextforeground}
856
857 \constfunc{const wxColour\&}{GetTextForeground}{\void}
858
859 Gets the current text foreground colour (see \helpref{wxDC::SetTextForeground}{wxdcsettextforeground}).
860
861
862 \membersection{wxDC::GetUserScale}\label{wxdcgetuserscale}
863
864 \func{void}{GetUserScale}{\param{double}{ *x}, \param{double}{ *y}}
865
866 Gets the current user scale factor (set by \helpref{SetUserScale}{wxdcsetuserscale}).
867
868 \perlnote{In wxPerl this method takes no arguments and return a two element
869 array {\tt ( x, y )}}
870
871
872 \membersection{wxDC::GradientFillConcentric}\label{wxdcgradientfillconcentric}
873
874 \func{void}{GradientFillConcentric}{\param{const wxRect\&}{ rect}, \param{const wxColour\&}{ initialColour}, \param{const wxColour\&}{ destColour}}
875
876 \func{void}{GradientFillConcentric}{\param{const wxRect\&}{ rect}, \param{const wxColour\&}{ initialColour}, \param{const wxColour\&}{ destColour}, \param{const wxPoint\& }{circleCenter}}
877
878 Fill the area specified by rect with a radial gradient, starting from
879 \arg{initialColour} at the centre of the circle and fading to \arg{destColour}
880 on the circle outside.
881
882 \arg{circleCenter} are the relative coordinates of centre of the circle in
883 the specified \arg{rect}. If not specified, the cercle is placed at the
884 centre of rect.
885
886 \textbf{Note: } Currently this function is very slow, don't use it for
887 real-time drawing.
888
889
890 \membersection{wxDC::GradientFillLinear}\label{wxdcgradientfilllinear}
891
892 \func{void}{GradientFillLinear}{\param{const wxRect\&}{ rect}, \param{const wxColour\&}{ initialColour}, \param{const wxColour\&}{ destColour}, \param{wxDirection}{ nDirection = wxEAST}}
893
894 Fill the area specified by \arg{rect} with a linear gradient, starting from
895 \arg{initialColour} and eventually fading to \arg{destColour}. The
896 \arg{nDirection} specifies the direction of the colour change, default is to
897 use \arg{initialColour} on the left part of the rectangle and
898 \arg{destColour} on the right one.
899
900
901 \membersection{wxDC::LogicalToDeviceX}\label{wxdclogicaltodevicex}
902
903 \func{virtual wxCoord}{LogicalToDeviceX}{\param{wxCoord}{ x}}
904
905 Converts logical X coordinate to device coordinate, using the current
906 mapping mode.
907
908
909 \membersection{wxDC::LogicalToDeviceXRel}\label{wxdclogicaltodevicexrel}
910
911 \func{virtual wxCoord}{LogicalToDeviceXRel}{\param{wxCoord}{ x}}
912
913 Converts logical X coordinate to relative device coordinate, using the current
914 mapping mode but ignoring the x axis orientation.
915 Use this for converting a width, for example.
916
917
918 \membersection{wxDC::LogicalToDeviceY}\label{wxdclogicaltodevicey}
919
920 \func{virtual wxCoord}{LogicalToDeviceY}{\param{wxCoord}{ y}}
921
922 Converts logical Y coordinate to device coordinate, using the current
923 mapping mode.
924
925
926 \membersection{wxDC::LogicalToDeviceYRel}\label{wxdclogicaltodeviceyrel}
927
928 \func{virtual wxCoord}{LogicalToDeviceYRel}{\param{wxCoord}{ y}}
929
930 Converts logical Y coordinate to relative device coordinate, using the current
931 mapping mode but ignoring the y axis orientation.
932 Use this for converting a height, for example.
933
934
935 \membersection{wxDC::MaxX}\label{wxdcmaxx}
936
937 \func{wxCoord}{MaxX}{\void}
938
939 Gets the maximum horizontal extent used in drawing commands so far.
940
941
942 \membersection{wxDC::MaxY}\label{wxdcmaxy}
943
944 \func{wxCoord}{MaxY}{\void}
945
946 Gets the maximum vertical extent used in drawing commands so far.
947
948
949 \membersection{wxDC::MinX}\label{wxdcminx}
950
951 \func{wxCoord}{MinX}{\void}
952
953 Gets the minimum horizontal extent used in drawing commands so far.
954
955
956 \membersection{wxDC::MinY}\label{wxdcminy}
957
958 \func{wxCoord}{MinY}{\void}
959
960 Gets the minimum vertical extent used in drawing commands so far.
961
962
963 \membersection{wxDC::IsOk}\label{wxdcisok}
964
965 \func{bool}{Ok}{\void}
966
967 Returns true if the DC is ok to use.
968
969
970 \membersection{wxDC::ResetBoundingBox}\label{wxdcresetboundingbox}
971
972 \func{void}{ResetBoundingBox}{\void}
973
974 Resets the bounding box: after a call to this function, the bounding box
975 doesn't contain anything.
976
977 \wxheading{See also}
978
979 \helpref{CalcBoundingBox}{wxdccalcboundingbox}
980
981
982 \membersection{wxDC::SetAxisOrientation}\label{wxdcsetaxisorientation}
983
984 \func{void}{SetAxisOrientation}{\param{bool}{ xLeftRight},
985 \param{bool}{ yBottomUp}}
986
987 Sets the x and y axis orientation (i.e., the direction from lowest to
988 highest values on the axis). The default orientation is
989 x axis from left to right and y axis from top down.
990
991 \wxheading{Parameters}
992
993 \docparam{xLeftRight}{True to set the x axis orientation to the natural
994 left to right orientation, false to invert it.}
995
996 \docparam{yBottomUp}{True to set the y axis orientation to the natural
997 bottom up orientation, false to invert it.}
998
999
1000 \membersection{wxDC::SetBackground}\label{wxdcsetbackground}
1001
1002 \func{void}{SetBackground}{\param{const wxBrush\& }{brush}}
1003
1004 Sets the current background brush for the DC.
1005
1006
1007 \membersection{wxDC::SetBackgroundMode}\label{wxdcsetbackgroundmode}
1008
1009 \func{void}{SetBackgroundMode}{\param{int}{ mode}}
1010
1011 {\it mode} may be one of wxSOLID and wxTRANSPARENT. This setting determines
1012 whether text will be drawn with a background colour or not.
1013
1014
1015 \membersection{wxDC::SetBrush}\label{wxdcsetbrush}
1016
1017 \func{void}{SetBrush}{\param{const wxBrush\& }{brush}}
1018
1019 Sets the current brush for the DC.
1020
1021 If the argument is wxNullBrush, the current brush is selected out of the device
1022 context (leaving wxDC without any valid brush), allowing the current brush to
1023 be destroyed safely.
1024
1025 See also \helpref{wxBrush}{wxbrush}.
1026
1027 See also \helpref{wxMemoryDC}{wxmemorydc} for the interpretation of colours
1028 when drawing into a monochrome bitmap.
1029
1030
1031 \membersection{wxDC::SetClippingRegion}\label{wxdcsetclippingregion}
1032
1033 \func{void}{SetClippingRegion}{\param{wxCoord}{ x}, \param{wxCoord}{ y}, \param{wxCoord}{ width}, \param{wxCoord}{ height}}
1034
1035 \func{void}{SetClippingRegion}{\param{const wxPoint\& }{pt}, \param{const wxSize\& }{sz}}
1036
1037 \func{void}{SetClippingRegion}{\param{const wxRect\&}{ rect}}
1038
1039 \func{void}{SetClippingRegion}{\param{const wxRegion\&}{ region}}
1040
1041 Sets the clipping region for this device context to the intersection of the
1042 given region described by the parameters of this method and the previously set
1043 clipping region. You should call
1044 \helpref{DestroyClippingRegion}{wxdcdestroyclippingregion} if you want to set
1045 the clipping region exactly to the region specified.
1046
1047 The clipping region is an area to which drawing is restricted. Possible uses
1048 for the clipping region are for clipping text or for speeding up window redraws
1049 when only a known area of the screen is damaged.
1050
1051 \wxheading{See also}
1052
1053 \helpref{wxDC::DestroyClippingRegion}{wxdcdestroyclippingregion}, \helpref{wxRegion}{wxregion}
1054
1055
1056 \membersection{wxDC::SetDeviceOrigin}\label{wxdcsetdeviceorigin}
1057
1058 \func{void}{SetDeviceOrigin}{\param{wxCoord}{ x}, \param{wxCoord}{ y}}
1059
1060 Sets the device origin (i.e., the origin in pixels after scaling has been
1061 applied).
1062
1063 This function may be useful in Windows printing
1064 operations for placing a graphic on a page.
1065
1066
1067 \membersection{wxDC::SetFont}\label{wxdcsetfont}
1068
1069 \func{void}{SetFont}{\param{const wxFont\& }{font}}
1070
1071 Sets the current font for the DC. It must be a valid font, in particular you
1072 should not pass {\tt wxNullFont} to this method.
1073
1074 See also \helpref{wxFont}{wxfont}.
1075
1076
1077 \membersection{wxDC::SetLayoutDirection}\label{wxdcsetlayoutdirection}
1078
1079 \func{void}{SetLayoutDirection}{\param{wxLayoutDirection}{ dir}}
1080
1081 Sets the current layout direction for the device context. \arg{dir} may be either
1082 \texttt{wxLayout\_Default}, \texttt{wxLayout\_LeftToRight} or \texttt{wxLayout\_RightToLeft}.
1083
1084 \wxheading{See also}
1085
1086 \helpref{GetLayoutDirection}{wxdcgetlayoutdirection}
1087
1088
1089 \membersection{wxDC::SetLogicalFunction}\label{wxdcsetlogicalfunction}
1090
1091 \func{void}{SetLogicalFunction}{\param{int}{ function}}
1092
1093 Sets the current logical function for the device context. This determines how
1094 a source pixel (from a pen or brush colour, or source device context if
1095 using \helpref{wxDC::Blit}{wxdcblit}) combines with a destination pixel in the
1096 current device context.
1097
1098 The possible values
1099 and their meaning in terms of source and destination pixel values are
1100 as follows:
1101
1102 \begin{verbatim}
1103 wxAND src AND dst
1104 wxAND_INVERT (NOT src) AND dst
1105 wxAND_REVERSE src AND (NOT dst)
1106 wxCLEAR 0
1107 wxCOPY src
1108 wxEQUIV (NOT src) XOR dst
1109 wxINVERT NOT dst
1110 wxNAND (NOT src) OR (NOT dst)
1111 wxNOR (NOT src) AND (NOT dst)
1112 wxNO_OP dst
1113 wxOR src OR dst
1114 wxOR_INVERT (NOT src) OR dst
1115 wxOR_REVERSE src OR (NOT dst)
1116 wxSET 1
1117 wxSRC_INVERT NOT src
1118 wxXOR src XOR dst
1119 \end{verbatim}
1120
1121 The default is wxCOPY, which simply draws with the current colour.
1122 The others combine the current colour and the background using a
1123 logical operation. wxINVERT is commonly used for drawing rubber bands or
1124 moving outlines, since drawing twice reverts to the original colour.
1125
1126
1127 \membersection{wxDC::SetMapMode}\label{wxdcsetmapmode}
1128
1129 \func{void}{SetMapMode}{\param{int}{ int}}
1130
1131 The {\it mapping mode} of the device context defines the unit of
1132 measurement used to convert logical units to device units. Note that
1133 in X, text drawing isn't handled consistently with the mapping mode; a
1134 font is always specified in point size. However, setting the {\it
1135 user scale} (see \helpref{wxDC::SetUserScale}{wxdcsetuserscale}) scales the text appropriately. In
1136 Windows, scalable TrueType fonts are always used; in X, results depend
1137 on availability of fonts, but usually a reasonable match is found.
1138
1139 The coordinate origin is always at the top left of the screen/printer.
1140
1141 Drawing to a Windows printer device context uses the current mapping mode,
1142 but mapping mode is currently ignored for PostScript output.
1143
1144 The mapping mode can be one of the following:
1145
1146 \begin{twocollist}\itemsep=0pt
1147 \twocolitem{wxMM\_TWIPS}{Each logical unit is 1/20 of a point, or 1/1440 of
1148 an inch.}
1149 \twocolitem{wxMM\_POINTS}{Each logical unit is a point, or 1/72 of an inch.}
1150 \twocolitem{wxMM\_METRIC}{Each logical unit is 1 mm.}
1151 \twocolitem{wxMM\_LOMETRIC}{Each logical unit is 1/10 of a mm.}
1152 \twocolitem{wxMM\_TEXT}{Each logical unit is 1 device pixel.}
1153 \end{twocollist}
1154
1155
1156 \membersection{wxDC::SetPalette}\label{wxdcsetpalette}
1157
1158 \func{void}{SetPalette}{\param{const wxPalette\& }{palette}}
1159
1160 If this is a window DC or memory DC, assigns the given palette to the window
1161 or bitmap associated with the DC. If the argument is wxNullPalette, the current
1162 palette is selected out of the device context, and the original palette
1163 restored.
1164
1165 See \helpref{wxPalette}{wxpalette} for further details.
1166
1167
1168 \membersection{wxDC::SetPen}\label{wxdcsetpen}
1169
1170 \func{void}{SetPen}{\param{const wxPen\& }{pen}}
1171
1172 Sets the current pen for the DC.
1173
1174 If the argument is wxNullPen, the current pen is selected out of the device
1175 context (leaving wxDC without any valid pen), allowing the current brush to
1176 be destroyed safely.
1177
1178 See also \helpref{wxMemoryDC}{wxmemorydc} for the interpretation of colours
1179 when drawing into a monochrome bitmap.
1180
1181
1182 \membersection{wxDC::SetTextBackground}\label{wxdcsettextbackground}
1183
1184 \func{void}{SetTextBackground}{\param{const wxColour\& }{colour}}
1185
1186 Sets the current text background colour for the DC.
1187
1188
1189 \membersection{wxDC::SetTextForeground}\label{wxdcsettextforeground}
1190
1191 \func{void}{SetTextForeground}{\param{const wxColour\& }{colour}}
1192
1193 Sets the current text foreground colour for the DC.
1194
1195 See also \helpref{wxMemoryDC}{wxmemorydc} for the interpretation of colours
1196 when drawing into a monochrome bitmap.
1197
1198
1199 \membersection{wxDC::SetUserScale}\label{wxdcsetuserscale}
1200
1201 \func{void}{SetUserScale}{\param{double}{ xScale}, \param{double}{ yScale}}
1202
1203 Sets the user scaling factor, useful for applications which require
1204 `zooming'.
1205
1206
1207 \membersection{wxDC::StartDoc}\label{wxdcstartdoc}
1208
1209 \func{bool}{StartDoc}{\param{const wxString\& }{message}}
1210
1211 Starts a document (only relevant when outputting to a printer).
1212 Message is a message to show while printing.
1213
1214
1215 \membersection{wxDC::StartPage}\label{wxdcstartpage}
1216
1217 \func{bool}{StartPage}{\void}
1218
1219 Starts a document page (only relevant when outputting to a printer).
1220
1221
1222 \membersection{wxDC::StretchBlit}\label{wxdcstretchblit}
1223
1224 \func{bool}{StretchBlit}{\param{wxCoord}{ xdest}, \param{wxCoord}{ ydest}, \param{wxCoord}{ dstWidth}, \param{wxCoord}{ dstHeight},
1225 \param{wxDC* }{source}, \param{wxCoord}{ xsrc}, \param{wxCoord}{ ysrc}, \param{wxCoord}{ srcWidth}, \param{wxCoord}{ srcHeight},
1226 \param{int}{ logicalFunc = wxCOPY}, \param{bool }{useMask = false}, \param{wxCoord}{ xsrcMask = -1}, \param{wxCoord}{ ysrcMask = -1}}
1227
1228 Copy from a source DC to this DC, specifying the destination
1229 coordinates, destination size, source DC, source coordinates,
1230 size of source area to copy, logical function, whether to use a bitmap mask,
1231 and mask source position.
1232
1233 \wxheading{Parameters}
1234
1235 \docparam{xdest}{Destination device context x position.}
1236
1237 \docparam{ydest}{Destination device context y position.}
1238
1239 \docparam{dstWidth}{Width of destination area.}
1240
1241 \docparam{dstHeight}{Height of destination area.}
1242
1243 \docparam{source}{Source device context.}
1244
1245 \docparam{xsrc}{Source device context x position.}
1246
1247 \docparam{ysrc}{Source device context y position.}
1248
1249 \docparam{srcWidth}{Width of source area to be copied.}
1250
1251 \docparam{srcHeight}{Height of source area to be copied.}
1252
1253 \docparam{logicalFunc}{Logical function to use: see \helpref{wxDC::SetLogicalFunction}{wxdcsetlogicalfunction}.}
1254
1255 \docparam{useMask}{If true, Blit does a transparent blit using the mask that is associated with the bitmap
1256 selected into the source device context. The Windows implementation does the following if \texttt{MaskBlt} cannot be used:
1257
1258 \begin{enumerate}
1259 \item Creates a temporary bitmap and copies the destination area into it.
1260 \item Copies the source area into the temporary bitmap using the specified logical function.
1261 \item Sets the masked area in the temporary bitmap to BLACK by ANDing the
1262 mask bitmap with the temp bitmap with the foreground colour set to WHITE
1263 and the background colour set to BLACK.
1264 \item Sets the unmasked area in the destination area to BLACK by ANDing the
1265 mask bitmap with the destination area with the foreground colour set to BLACK
1266 and the background colour set to WHITE.
1267 \item ORs the temporary bitmap with the destination area.
1268 \item Deletes the temporary bitmap.
1269 \end{enumerate}
1270
1271 This sequence of operations ensures that the source's transparent area need not be black,
1272 and logical functions are supported.
1273
1274 {\bf Note:} on Windows, blitting with masks can be speeded up considerably by compiling
1275 wxWidgets with the \texttt{wxUSE\_DC\_CACHE} option enabled. You can also influence whether \texttt{MaskBlt}
1276 or the explicit mask blitting code above is used, by using \helpref{wxSystemOptions}{wxsystemoptions} and
1277 setting the {\bf no-maskblt} option to 1.
1278
1279 }
1280
1281 \docparam{xsrcMask}{Source x position on the mask. If both xsrcMask and ysrcMask are -1, xsrc and ysrc
1282 will be assumed for the mask source position. Currently only implemented on Windows.}
1283
1284 \docparam{ysrcMask}{Source y position on the mask. If both xsrcMask and ysrcMask are -1, xsrc and ysrc
1285 will be assumed for the mask source position. Currently only implemented on Windows.}
1286
1287
1288 \wxheading{Remarks}
1289
1290 There is partial support for Blit in wxPostScriptDC, under X.
1291
1292 wxDC::StretchBlit is only implemented under wxMAC and wxMSW.
1293
1294 See \helpref{wxMemoryDC}{wxmemorydc} for typical usage.
1295
1296 \newsince{2.9.0}
1297
1298 \wxheading{See also}
1299
1300 \helpref{wxDC::Blit}{wxdcblit}, \helpref{wxMemoryDC}{wxmemorydc}, \helpref{wxBitmap}{wxbitmap}, \helpref{wxMask}{wxmask}
1301