interface/wx/dc.h

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        dc.h
   3 // Purpose:     interface of wxDC
   4 // Author:      wxWidgets team
   5 // RCS-ID:      $Id$
   6 // Licence:     wxWindows licence
   7 /////////////////////////////////////////////////////////////////////////////
   8
   9
  10 /**
  11     Logical raster operations which can be used with wxDC::SetLogicalFunction
  12     and some other wxDC functions (e.g. wxDC::Blit and wxDC::StretchBlit).
  13
  14     The description of the values below refer to how a generic @e src source pixel
  15     and the corresponding @e dst destination pixel gets combined together to produce
  16     the final pixel. E.g. @c wxCLEAR and @c wxSET completely ignore the source
  17     and the destination pixel and always put zeroes or ones in the final surface.
  18 */
  19 enum wxRasterOperationMode
  20 {
  21     wxCLEAR,       //!< 0
  22     wxXOR,         //!< @e src XOR @e dst
  23     wxINVERT,      //!< NOT @e dst
  24     wxOR_REVERSE,  //!< @e src OR (NOT @e dst)
  25     wxAND_REVERSE, //!< @e src AND (NOT @e dst)
  26     wxCOPY,        //!< @e src
  27     wxAND,         //!< @e src AND @e dst
  28     wxAND_INVERT,  //!< (NOT @e src) AND @e dst
  29     wxNO_OP,       //!< @e dst
  30     wxNOR,         //!< (NOT @e src) AND (NOT @e dst)
  31     wxEQUIV,       //!< (NOT @e src) XOR @e dst
  32     wxSRC_INVERT,  //!< (NOT @e src)
  33     wxOR_INVERT,   //!< (NOT @e src) OR @e dst
  34     wxNAND,        //!< (NOT @e src) OR (NOT @e dst)
  35     wxOR,          //!< @e src OR @e dst
  36     wxSET          //!< 1
  37 };
  38
  39 /**
  40     Flood styles used by wxDC::FloodFill.
  41 */
  42 enum wxFloodFillStyle
  43 {
  44     /** The flooding occurs until a colour other than the given colour is encountered. */
  45     wxFLOOD_SURFACE = 1,
  46
  47     /** The area to be flooded is bounded by the given colour. */
  48     wxFLOOD_BORDER
  49 };
  50
  51 /**
  52     The mapping used to transform @e logical units to @e device units.
  53     See wxDC::SetMapMode.
  54 */
  55 enum wxMappingMode
  56 {
  57     /**
  58         Each logical unit is 1 device pixel.
  59         This is the default mapping mode for all wxDC-derived classes.
  60     */
  61     wxMM_TEXT = 1,
  62
  63     /** Each logical unit is 1 millimeter. */
  64     wxMM_METRIC,
  65
  66     /** Each logical unit is 1/10 of a millimeter. */
  67     wxMM_LOMETRIC,
  68
  69     /**
  70         Each logical unit is 1/20 of a @e "printer point", or 1/1440 of an inch
  71         (also known as "twip"). Equivalent to about 17.64 micrometers.
  72     */
  73     wxMM_TWIPS,
  74
  75     /**
  76         Each logical unit is a @e "printer point" i.e. 1/72 of an inch.
  77         Equivalent to about 353 micrometers.
  78     */
  79     wxMM_POINTS
  80 };
  81
  82 /**
  83     Simple collection of various font metrics.
  84
  85     This object is returned by wxDC::GetFontMetrics().
  86
  87     @since 2.9.2
  88
  89     @library{wxcore}
  90     @category{dc,gdi}
  91  */
  92 struct wxFontMetrics
  93 {
  94     /// Constructor initializes all fields to 0.
  95     wxFontMetrics();
  96
  97     int height,             ///< Total character height.
  98         ascent,             ///< Part of the height above the baseline.
  99         descent,            ///< Part of the height below the baseline.
 100         internalLeading,    ///< Intra-line spacing.
 101         externalLeading,    ///< Inter-line spacing.
 102         averageWidth;       ///< Average font width, a.k.a. "x-width".
 103 };
 104
 105
 106 /**
 107     @class wxDC
 108
 109     A wxDC is a @e "device context" onto which graphics and text can be drawn.
 110     It is intended to represent different output devices and offers a common
 111     abstract API for drawing on any of them.
 112
 113     wxWidgets offers an alternative drawing API based on the modern drawing
 114     backends GDI+, CoreGraphics and Cairo. See wxGraphicsContext, wxGraphicsRenderer
 115     and related classes. There is also a wxGCDC linking the APIs by offering
 116     the wxDC API on top of a wxGraphicsContext.
 117
 118     wxDC is an abstract base class and cannot be created directly.
 119     Use wxPaintDC, wxClientDC, wxWindowDC, wxScreenDC, wxMemoryDC or
 120     wxPrinterDC. Notice that device contexts which are associated with windows
 121     (i.e. wxClientDC, wxWindowDC and wxPaintDC) use the window font and colours
 122     by default (starting with wxWidgets 2.9.0) but the other device context
 123     classes use system-default values so you always must set the appropriate
 124     fonts and colours before using them.
 125
 126     In addition to the versions of the methods documented below, there
 127     are also versions which accept single wxPoint parameter instead
 128     of the two wxCoord ones or wxPoint and wxSize instead of the four
 129     wxCoord parameters.
 130
 131     Beginning with wxWidgets 2.9.0 the entire wxDC code has been
 132     reorganized. All platform dependent code (actually all drawing code)
 133     has been moved into backend classes which derive from a common
 134     wxDCImpl class. The user-visible classes such as wxClientDC and
 135     wxPaintDC merely forward all calls to the backend implementation.
 136
 137
 138     @section dc_units Device and logical units
 139
 140     In the wxDC context there is a distinction between @e logical units and @e device units.
 141
 142     @b Device units are the units native to the particular device; e.g. for a screen,
 143     a device unit is a @e pixel. For a printer, the device unit is defined by the
 144     resolution of the printer (usually given in @c DPI: dot-per-inch).
 145
 146     All wxDC functions use instead @b logical units, unless where explicitly
 147     stated. Logical units are arbitrary units mapped to device units using
 148     the current mapping mode (see wxDC::SetMapMode).
 149
 150     This mechanism allows to reuse the same code which prints on e.g. a window
 151     on the screen to print on e.g. a paper.
 152
 153
 154     @section dc_alpha_support Support for Transparency / Alpha Channel
 155
 156     In general wxDC methods don't support alpha transparency and the alpha
 157     component of wxColour is simply ignored and you need to use wxGraphicsContext
 158     for full transparency support. There are, however, a few exceptions: first,
 159     under Mac OS X colours with alpha channel are supported in all the normal
 160     wxDC-derived classes as they use wxGraphicsContext internally. Second,
 161     under all platforms wxSVGFileDC also fully supports alpha channel. In both
 162     of these cases the instances of wxPen or wxBrush that are built from
 163     wxColour use the colour's alpha values when stroking or filling.
 164
 165
 166     @section Support for Transformation Matrix
 167
 168     On some platforms (currently only under MSW and only on Windows NT, i.e.
 169     not Windows 9x/ME, systems) wxDC has support for applying an arbitrary
 170     affine transformation matrix to its coordinate system. Call
 171     CanUseTransformMatrix() to check if this support is available and then call
 172     SetTransformMatrix() if it is. If the transformation matrix is not
 173     supported, SetTransformMatrix() always simply returns false and doesn't do
 174     anything.
 175
 176
 177     @library{wxcore}
 178     @category{dc,gdi}
 179
 180     @see @ref overview_dc, wxGraphicsContext, wxDCFontChanger, wxDCTextColourChanger,
 181          wxDCPenChanger, wxDCBrushChanger, wxDCClipper
 182
 183     @todo Precise definition of default/initial state.
 184     @todo Pixelwise definition of operations (e.g. last point of a line not
 185           drawn).
 186 */
 187 class wxDC : public wxObject
 188 {
 189 public:
 190     /**
 191         @name Coordinate conversion functions
 192     */
 193     //@{
 194
 195     /**
 196         Convert @e device X coordinate to logical coordinate, using the current
 197         mapping mode, user scale factor, device origin and axis orientation.
 198     */
 199     wxCoord DeviceToLogicalX(wxCoord x) const;
 200
 201     /**
 202         Convert @e device X coordinate to relative logical coordinate, using the
 203         current mapping mode and user scale factor but ignoring the
 204         axis orientation. Use this for converting a width, for example.
 205     */
 206     wxCoord DeviceToLogicalXRel(wxCoord x) const;
 207
 208     /**
 209         Converts @e device Y coordinate to logical coordinate, using the current
 210         mapping mode, user scale factor, device origin and axis orientation.
 211     */
 212     wxCoord DeviceToLogicalY(wxCoord y) const;
 213
 214     /**
 215         Convert @e device Y coordinate to relative logical coordinate, using the
 216         current mapping mode and user scale factor but ignoring the
 217         axis orientation. Use this for converting a height, for example.
 218     */
 219     wxCoord DeviceToLogicalYRel(wxCoord y) const;
 220
 221     /**
 222         Converts logical X coordinate to device coordinate, using the current
 223         mapping mode, user scale factor, device origin and axis orientation.
 224     */
 225     wxCoord LogicalToDeviceX(wxCoord x) const;
 226
 227     /**
 228         Converts logical X coordinate to relative device coordinate, using the
 229         current mapping mode and user scale factor but ignoring the
 230         axis orientation. Use this for converting a width, for example.
 231     */
 232     wxCoord LogicalToDeviceXRel(wxCoord x) const;
 233
 234     /**
 235         Converts logical Y coordinate to device coordinate, using the current
 236         mapping mode, user scale factor, device origin and axis orientation.
 237     */
 238     wxCoord LogicalToDeviceY(wxCoord y) const;
 239
 240     /**
 241         Converts logical Y coordinate to relative device coordinate, using the
 242         current mapping mode and user scale factor but ignoring the
 243         axis orientation. Use this for converting a height, for example.
 244     */
 245     wxCoord LogicalToDeviceYRel(wxCoord y) const;
 246
 247     //@}
 248
 249
 250
 251     /**
 252         @name Drawing functions
 253     */
 254     //@{
 255
 256     /**
 257         Clears the device context using the current background brush.
 258     */
 259     void Clear();
 260
 261     /**
 262         Draws an arc of a circle, centred on (@a xc, @a yc), with starting
 263         point (@a xStart, @a yStart) and ending at (@a xEnd, @a yEnd).
 264         The current pen is used for the outline and the current brush for
 265         filling the shape.
 266
 267         The arc is drawn in a counter-clockwise direction from the start point
 268         to the end point.
 269     */
 270     void DrawArc(wxCoord xStart, wxCoord yStart, wxCoord xEnd, wxCoord yEnd,
 271                  wxCoord xc, wxCoord yc);
 272
 273     /**
 274         @overload
 275     */
 276     void DrawArc(const wxPoint& ptStart, const wxPoint& ptEnd, const wxPoint& centre);
 277
 278     /**
 279         Draw a bitmap on the device context at the specified point. If
 280         @a transparent is @true and the bitmap has a transparency mask, the
 281         bitmap will be drawn transparently.
 282
 283         When drawing a mono-bitmap, the current text foreground colour will be
 284         used to draw the foreground of the bitmap (all bits set to 1), and the
 285         current text background colour to draw the background (all bits set to
 286         0).
 287
 288         @see SetTextForeground(), SetTextBackground(), wxMemoryDC
 289     */
 290     void DrawBitmap(const wxBitmap& bitmap, wxCoord x, wxCoord y,
 291                     bool useMask = false);
 292
 293     /**
 294         @overload
 295     */
 296     void DrawBitmap(const wxBitmap &bmp, const wxPoint& pt,
 297                     bool useMask = false);
 298
 299     /**
 300         Draws a check mark inside the given rectangle.
 301     */
 302     void DrawCheckMark(wxCoord x, wxCoord y, wxCoord width, wxCoord height);
 303
 304     /**
 305         @overload
 306     */
 307     void DrawCheckMark(const wxRect& rect);
 308
 309     /**
 310         Draws a circle with the given centre and radius.
 311
 312         @see DrawEllipse()
 313     */
 314     void DrawCircle(wxCoord x, wxCoord y, wxCoord radius);
 315
 316     /**
 317         @overload
 318     */
 319     void DrawCircle(const wxPoint& pt, wxCoord radius);
 320
 321     /**
 322         Draws an ellipse contained in the rectangle specified either with the
 323         given top left corner and the given size or directly. The current pen
 324         is used for the outline and the current brush for filling the shape.
 325
 326         @see DrawCircle()
 327     */
 328     void DrawEllipse(wxCoord x, wxCoord y, wxCoord width, wxCoord height);
 329
 330     /**
 331         @overload
 332     */
 333     void DrawEllipse(const wxPoint& pt, const wxSize& size);
 334
 335     /**
 336         @overload
 337     */
 338     void DrawEllipse(const wxRect& rect);
 339
 340     /**
 341         Draws an arc of an ellipse. The current pen is used for drawing the arc
 342         and the current brush is used for drawing the pie.
 343
 344         @a x and @a y specify the x and y coordinates of the upper-left corner
 345         of the rectangle that contains the ellipse.
 346
 347         @a width and @a height specify the width and height of the rectangle
 348         that contains the ellipse.
 349
 350         @a start and @a end specify the start and end of the arc relative to
 351         the three-o'clock position from the center of the rectangle. Angles are
 352         specified in degrees (360 is a complete circle). Positive values mean
 353         counter-clockwise motion. If @a start is equal to @e end, a complete
 354         ellipse will be drawn.
 355     */
 356     void DrawEllipticArc(wxCoord x, wxCoord y, wxCoord width, wxCoord height,
 357                           double start, double end);
 358
 359     /**
 360         @overload
 361     */
 362     void DrawEllipticArc(const wxPoint& pt, const wxSize& sz,
 363                          double sa, double ea);
 364
 365     /**
 366         Draw an icon on the display (does nothing if the device context is
 367         PostScript). This can be the simplest way of drawing bitmaps on a
 368         window.
 369     */
 370     void DrawIcon(const wxIcon& icon, wxCoord x, wxCoord y);
 371
 372     /**
 373         @overload
 374     */
 375     void DrawIcon(const wxIcon& icon, const wxPoint& pt);
 376
 377     /**
 378         Draw optional bitmap and the text into the given rectangle and aligns
 379         it as specified by alignment parameter; it also will emphasize the
 380         character with the given index if it is != -1 and return the bounding
 381         rectangle if required.
 382     */
 383     void DrawLabel(const wxString& text, const wxBitmap& bitmap,
 384                    const wxRect& rect,
 385                    int alignment = wxALIGN_LEFT | wxALIGN_TOP,
 386                    int indexAccel = -1, wxRect* rectBounding = NULL);
 387
 388     /**
 389         @overload
 390     */
 391     void DrawLabel(const wxString& text, const wxRect& rect,
 392                    int alignment = wxALIGN_LEFT | wxALIGN_TOP,
 393                    int indexAccel = -1);
 394
 395     /**
 396         Draws a line from the first point to the second. The current pen is
 397         used for drawing the line. Note that the point (@a x2, @a y2) is not
 398         part of the line and is not drawn by this function (this is consistent
 399         with the behaviour of many other toolkits).
 400     */
 401     void DrawLine(wxCoord x1, wxCoord y1, wxCoord x2, wxCoord y2);
 402
 403     /**
 404         @overload
 405     */
 406     void DrawLine(const wxPoint& pt1, const wxPoint& pt2);
 407
 408     /**
 409         Draws lines using an array of points of size @a n adding the optional
 410         offset coordinate. The current pen is used for drawing the lines.
 411
 412         @beginWxPythonOnly
 413         The wxPython version of this method accepts a Python list of wxPoint
 414         objects.
 415         @endWxPythonOnly
 416
 417         @beginWxPerlOnly
 418         Not supported by wxPerl.
 419         @endWxPerlOnly
 420     */
 421     void DrawLines(int n, wxPoint points[], wxCoord xoffset = 0,
 422                    wxCoord yoffset = 0);
 423     /**
 424         This method uses a list of wxPoints, adding the optional offset
 425         coordinate. The programmer is responsible for deleting the list of
 426         points.
 427
 428         @beginWxPythonOnly
 429         The wxPython version of this method accepts a Python list of wxPoint
 430         objects.
 431         @endWxPythonOnly
 432
 433         @beginWxPerlOnly
 434         The wxPerl version of this method accepts
 435         as its first parameter a reference to an array
 436         of wxPoint objects.
 437         @endWxPerlOnly
 438     */
 439     void DrawLines(const wxPointList* points,
 440                    wxCoord xoffset = 0, wxCoord yoffset = 0);
 441
 442     /**
 443         Draws a point using the color of the current pen. Note that the other
 444         properties of the pen are not used, such as width.
 445     */
 446     void DrawPoint(wxCoord x, wxCoord y);
 447
 448     /**
 449         @overload
 450     */
 451     void DrawPoint(const wxPoint& pt);
 452
 453     /**
 454         Draws a filled polygon using an array of points of size @a n, adding
 455         the optional offset coordinate. The first and last points are
 456         automatically closed.
 457
 458         The last argument specifies the fill rule: @b wxODDEVEN_RULE (the
 459         default) or @b wxWINDING_RULE.
 460
 461         The current pen is used for drawing the outline, and the current brush
 462         for filling the shape. Using a transparent brush suppresses filling.
 463
 464         @beginWxPerlOnly
 465         Not supported by wxPerl.
 466         @endWxPerlOnly
 467     */
 468     void DrawPolygon(int n, wxPoint points[], wxCoord xoffset = 0,
 469                      wxCoord yoffset = 0,
 470                      wxPolygonFillMode fill_style = wxODDEVEN_RULE);
 471     /**
 472         This method draws a filled polygon using a list of wxPoints, adding the
 473         optional offset coordinate. The first and last points are automatically
 474         closed.
 475
 476         The last argument specifies the fill rule: @b wxODDEVEN_RULE (the
 477         default) or @b wxWINDING_RULE.
 478
 479         The current pen is used for drawing the outline, and the current brush
 480         for filling the shape. Using a transparent brush suppresses filling.
 481
 482         The programmer is responsible for deleting the list of points.
 483
 484         @beginWxPythonOnly
 485         The wxPython version of this method accepts a Python list of wxPoint
 486         objects.
 487         @endWxPythonOnly
 488
 489         @beginWxPerlOnly
 490         The wxPerl version of this method accepts
 491         as its first parameter a reference to an array
 492         of wxPoint objects.
 493         @endWxPerlOnly
 494     */
 495     void DrawPolygon(const wxPointList* points,
 496                      wxCoord xoffset = 0, wxCoord yoffset = 0,
 497                      wxPolygonFillMode fill_style = wxODDEVEN_RULE);
 498
 499     /**
 500         Draws two or more filled polygons using an array of @a points, adding
 501         the optional offset coordinates.
 502
 503         Notice that for the platforms providing a native implementation of this
 504         function (Windows and PostScript-based wxDC currently), this is more
 505         efficient than using DrawPolygon() in a loop.
 506
 507         @a n specifies the number of polygons to draw, the array @e count of
 508         size @a n specifies the number of points in each of the polygons in the
 509         @a points array.
 510
 511         The last argument specifies the fill rule: @b wxODDEVEN_RULE (the
 512         default) or @b wxWINDING_RULE.
 513
 514         The current pen is used for drawing the outline, and the current brush
 515         for filling the shape. Using a transparent brush suppresses filling.
 516
 517         The polygons maybe disjoint or overlapping. Each polygon specified in a
 518         call to DrawPolyPolygon() must be closed. Unlike polygons created by
 519         the DrawPolygon() member function, the polygons created by this
 520         method are not closed automatically.
 521
 522         @beginWxPythonOnly
 523         Not implemented yet.
 524         @endWxPythonOnly
 525     */
 526     void DrawPolyPolygon(int n, int count[], wxPoint points[],
 527                          wxCoord xoffset = 0, wxCoord yoffset = 0,
 528                          wxPolygonFillMode fill_style = wxODDEVEN_RULE);
 529
 530     /**
 531         Draws a rectangle with the given top left corner, and with the given
 532         size.  The current pen is used for the outline and the current brush
 533         for filling the shape.
 534     */
 535     void DrawRectangle(wxCoord x, wxCoord y, wxCoord width, wxCoord height);
 536
 537     /**
 538         @overload
 539     */
 540     void DrawRectangle(const wxPoint& pt, const wxSize& sz);
 541
 542     /**
 543         @overload
 544     */
 545     void DrawRectangle(const wxRect& rect);
 546
 547     /**
 548         Draws the text rotated by @a angle degrees
 549         (positive angles are counterclockwise; the full angle is 360 degrees).
 550
 551         @note Under Win9x only TrueType fonts can be drawn by this function. In
 552               particular, a font different from @c wxNORMAL_FONT should be used
 553               as the latter is not a TrueType font. @c wxSWISS_FONT is an
 554               example of a font which is.
 555
 556         @see DrawText()
 557     */
 558     void DrawRotatedText(const wxString& text, wxCoord x, wxCoord y,
 559                          double angle);
 560
 561     /**
 562         @overload
 563     */
 564     void DrawRotatedText(const wxString& text, const wxPoint& point,
 565                          double angle);
 566
 567     /**
 568         Draws a rectangle with the given top left corner, and with the given
 569         size. The corners are quarter-circles using the given radius. The
 570         current pen is used for the outline and the current brush for filling
 571         the shape.
 572
 573         If @a radius is positive, the value is assumed to be the radius of the
 574         rounded corner. If @a radius is negative, the absolute value is assumed
 575         to be the @e proportion of the smallest dimension of the rectangle.
 576         This means that the corner can be a sensible size relative to the size
 577         of the rectangle, and also avoids the strange effects X produces when
 578         the corners are too big for the rectangle.
 579     */
 580     void DrawRoundedRectangle(wxCoord x, wxCoord y, wxCoord width,
 581                               wxCoord height, double radius);
 582
 583     /**
 584         @overload
 585     */
 586     void DrawRoundedRectangle(const wxPoint& pt, const wxSize& sz,
 587                               double radius);
 588
 589     /**
 590         @overload
 591     */
 592     void DrawRoundedRectangle(const wxRect& rect, double radius);
 593
 594     /**
 595         Draws a spline between all given points using the current pen.
 596
 597         @beginWxPythonOnly
 598         The wxPython version of this method accepts a Python list of wxPoint
 599         objects.
 600         @endWxPythonOnly
 601
 602         @beginWxPerlOnly
 603         Not supported by wxPerl.
 604         @endWxPerlOnly
 605     */
 606     void DrawSpline(int n, wxPoint points[]);
 607
 608     /**
 609         @overload
 610
 611
 612         @beginWxPerlOnly
 613         The wxPerl version of this method accepts
 614         as its first parameter a reference to an array
 615         of wxPoint objects.
 616         @endWxPerlOnly
 617     */
 618     void DrawSpline(const wxPointList* points);
 619
 620     /**
 621         @overload
 622
 623
 624         @beginWxPerlOnly
 625         Not supported by wxPerl.
 626         @endWxPerlOnly
 627     */
 628     void DrawSpline(wxCoord x1, wxCoord y1, wxCoord x2, wxCoord y2,
 629                     wxCoord x3, wxCoord y3);
 630
 631     /**
 632         Draws a text string at the specified point, using the current text
 633         font, and the current text foreground and background colours.
 634
 635         The coordinates refer to the top-left corner of the rectangle bounding
 636         the string. See GetTextExtent() for how to get the dimensions of a text
 637         string, which can be used to position the text more precisely and
 638         DrawLabel() if you need to align the string differently.
 639
 640         Starting from wxWidgets 2.9.2 @a text parameter can be a multi-line
 641         string, i.e. contain new line characters, and will be rendered
 642         correctly.
 643
 644         @note The current @ref GetLogicalFunction() "logical function" is
 645               ignored by this function.
 646     */
 647     void DrawText(const wxString& text, wxCoord x, wxCoord y);
 648
 649     /**
 650         @overload
 651     */
 652     void DrawText(const wxString& text, const wxPoint& pt);
 653
 654     /**
 655         Fill the area specified by rect with a radial gradient, starting from
 656         @a initialColour at the centre of the circle and fading to
 657         @a destColour on the circle outside.
 658
 659         The circle is placed at the centre of @a rect.
 660
 661         @note Currently this function is very slow, don't use it for real-time
 662               drawing.
 663     */
 664     void GradientFillConcentric(const wxRect& rect,
 665                                 const wxColour& initialColour,
 666                                 const wxColour& destColour);
 667
 668     /**
 669         Fill the area specified by rect with a radial gradient, starting from
 670         @a initialColour at the centre of the circle and fading to
 671         @a destColour on the circle outside.
 672
 673         @a circleCenter are the relative coordinates of centre of the circle in
 674         the specified @a rect.
 675
 676         @note Currently this function is very slow, don't use it for real-time
 677               drawing.
 678     */
 679     void GradientFillConcentric(const wxRect& rect,
 680                                 const wxColour& initialColour,
 681                                 const wxColour& destColour,
 682                                 const wxPoint& circleCenter);
 683
 684     /**
 685         Fill the area specified by @a rect with a linear gradient, starting
 686         from @a initialColour and eventually fading to @e destColour.
 687
 688         The @a nDirection specifies the direction of the colour change, default is
 689         to use @a initialColour on the left part of the rectangle and
 690         @a destColour on the right one.
 691     */
 692     void GradientFillLinear(const wxRect& rect, const wxColour& initialColour,
 693                             const wxColour& destColour,
 694                             wxDirection nDirection = wxRIGHT);
 695
 696     /**
 697         Flood fills the device context starting from the given point, using
 698         the current brush colour, and using a style:
 699
 700         - wxFLOOD_SURFACE: The flooding occurs until a colour other than the
 701           given colour is encountered.
 702         - wxFLOOD_BORDER: The area to be flooded is bounded by the given
 703           colour.
 704
 705         @return @false if the operation failed.
 706
 707         @note The present implementation for non-Windows platforms may fail to
 708               find colour borders if the pixels do not match the colour
 709               exactly. However the function will still return @true.
 710
 711         @note This method shouldn't be used with wxPaintDC under non-Windows
 712               platforms as it uses GetPixel() internally and this may give
 713               wrong results, notably in wxGTK. If you need to flood fill
 714               wxPaintDC, create a temporary wxMemoryDC, flood fill it and then
 715               blit it to, or draw as a bitmap on, wxPaintDC. See the example of
 716               doing this in the drawing sample and wxBufferedPaintDC class.
 717     */
 718     bool FloodFill(wxCoord x, wxCoord y, const wxColour& colour,
 719                    wxFloodFillStyle style = wxFLOOD_SURFACE);
 720
 721     /**
 722         @overload
 723     */
 724     bool FloodFill(const wxPoint& pt, const wxColour& col,
 725                    wxFloodFillStyle style = wxFLOOD_SURFACE);
 726
 727     /**
 728         Displays a cross hair using the current pen. This is a vertical and
 729         horizontal line the height and width of the window, centred on the
 730         given point.
 731     */
 732     void CrossHair(wxCoord x, wxCoord y);
 733
 734     /**
 735         @overload
 736     */
 737     void CrossHair(const wxPoint& pt);
 738
 739     //@}
 740
 741
 742     /**
 743         @name Clipping region functions
 744     */
 745     //@{
 746
 747     /**
 748         Destroys the current clipping region so that none of the DC is clipped.
 749
 750         @see SetClippingRegion()
 751     */
 752     void DestroyClippingRegion();
 753
 754     /**
 755         Gets the rectangle surrounding the current clipping region.
 756
 757         @beginWxPythonOnly
 758         No arguments are required and the four values defining the rectangle
 759         are returned as a tuple.
 760         @endWxPythonOnly
 761     */
 762     void GetClippingBox(wxCoord *x, wxCoord *y, wxCoord *width, wxCoord *height) const;
 763
 764     /**
 765         Sets the clipping region for this device context to the intersection of
 766         the given region described by the parameters of this method and the
 767         previously set clipping region.
 768
 769         The clipping region is an area to which drawing is restricted. Possible
 770         uses for the clipping region are for clipping text or for speeding up
 771         window redraws when only a known area of the screen is damaged.
 772
 773         Notice that you need to call DestroyClippingRegion() if you want to set
 774         the clipping region exactly to the region specified.
 775
 776         Also note that if the clipping region is empty, any previously set
 777         clipping region is destroyed, i.e. it is equivalent to calling
 778         DestroyClippingRegion(), and not to clipping out all drawing on the DC
 779         as might be expected.
 780
 781         @see DestroyClippingRegion(), wxRegion
 782     */
 783     void SetClippingRegion(wxCoord x, wxCoord y, wxCoord width, wxCoord height);
 784
 785     /**
 786         @overload
 787     */
 788     void SetClippingRegion(const wxPoint& pt, const wxSize& sz);
 789
 790     /**
 791         @overload
 792     */
 793     void SetClippingRegion(const wxRect& rect);
 794
 795     /**
 796         Sets the clipping region for this device context.
 797
 798         Unlike SetClippingRegion(), this function works with physical
 799         coordinates and not with the logical ones.
 800      */
 801     void SetDeviceClippingRegion(const wxRegion& region);
 802
 803     //@}
 804
 805
 806     /**
 807         @name Text/character extent functions
 808     */
 809     //@{
 810
 811     /**
 812         Gets the character height of the currently set font.
 813     */
 814     wxCoord GetCharHeight() const;
 815
 816     /**
 817         Gets the average character width of the currently set font.
 818     */
 819     wxCoord GetCharWidth() const;
 820
 821     /**
 822         Returns the various font characteristics.
 823
 824         This method allows to retrieve some of the font characteristics not
 825         returned by GetTextExtent(), notably internal leading and average
 826         character width.
 827
 828         Currently this method returns correct results only under wxMSW, in the
 829         other ports the internal leading will always be 0 and the average
 830         character width will be computed as the width of the character 'x'.
 831
 832         @since 2.9.2
 833      */
 834     wxFontMetrics GetFontMetrics() const;
 835
 836     /**
 837         Gets the dimensions of the string using the currently selected font.
 838         @a string is the text string to measure, @e heightLine, if non @NULL,
 839         is where to store the height of a single line.
 840
 841         The text extent is set in the given @a w and @a h pointers.
 842
 843         If the optional parameter @a font is specified and valid, then it is
 844         used for the text extent calculation, otherwise the currently selected
 845         font is used.
 846
 847         @note This function works with both single-line and multi-line strings.
 848
 849         @beginWxPerlOnly
 850         In wxPerl this method is implemented as
 851         GetMultiLineTextExtent(string, font = undef) returning a
 852         3-element list (width, height, line_height)
 853         @endWxPerlOnly
 854
 855         @see wxFont, SetFont(), GetPartialTextExtents(), GetTextExtent()
 856     */
 857     void GetMultiLineTextExtent(const wxString& string, wxCoord* w,
 858                                 wxCoord* h,
 859                                 wxCoord* heightLine = NULL,
 860                                 const wxFont* font = NULL) const;
 861     /**
 862         Gets the dimensions of the string using the currently selected font.
 863         @a string is the text string to measure, @e heightLine, if non @NULL,
 864         is where to store the height of a single line.
 865
 866         @return The text extent as a wxSize object.
 867
 868         @note This function works with both single-line and multi-line strings.
 869
 870         @beginWxPerlOnly
 871         Not supported by wxPerl.
 872         @endWxPerlOnly
 873
 874         @see wxFont, SetFont(), GetPartialTextExtents(), GetTextExtent()
 875     */
 876     wxSize GetMultiLineTextExtent(const wxString& string) const;
 877
 878     /**
 879         Fills the @a widths array with the widths from the beginning of @a text
 880         to the corresponding character of @a text. The generic version simply
 881         builds a running total of the widths of each character using
 882         GetTextExtent(), however if the various platforms have a native API
 883         function that is faster or more accurate than the generic
 884         implementation then it should be used instead.
 885
 886         @beginWxPythonOnly
 887         This method only takes the @a text parameter and returns a Python list
 888         of integers.
 889         @endWxPythonOnly
 890
 891         @beginWxPerlOnly
 892         In wxPerl this method only takes the @a text parameter and
 893         returns the widths as a list of integers.
 894         @endWxPerlOnly
 895
 896         @see GetMultiLineTextExtent(), GetTextExtent()
 897     */
 898     bool GetPartialTextExtents(const wxString& text,
 899                                wxArrayInt& widths) const;
 900
 901     /**
 902         Gets the dimensions of the string using the currently selected font.
 903         @a string is the text string to measure, @a descent is the dimension
 904         from the baseline of the font to the bottom of the descender, and
 905         @a externalLeading is any extra vertical space added to the font by the
 906         font designer (usually is zero).
 907
 908         The text extent is returned in @a w and @a h pointers or as a wxSize
 909         object depending on which version of this function is used.
 910
 911         If the optional parameter @a font is specified and valid, then it is
 912         used for the text extent calculation. Otherwise the currently selected
 913         font is.
 914
 915         @note This function only works with single-line strings.
 916
 917         @beginWxPythonOnly
 918         The following methods are implemented in wxPython:
 919         - GetTextExtent(string) - Returns a 2-tuple, (width, height).
 920         - GetFullTextExtent(string, font=NULL) -
 921             Returns a 4-tuple, (width, height, descent, externalLeading).
 922         @endWxPythonOnly
 923
 924         @beginWxPerlOnly
 925         In wxPerl this method is implemented as GetTextExtent(string,
 926         font = undef) returning a 4-element list (width, height,
 927         descent, externalLeading)
 928         @endWxPerlOnly
 929
 930         @see wxFont, SetFont(), GetPartialTextExtents(),
 931              GetMultiLineTextExtent()
 932     */
 933     void GetTextExtent(const wxString& string, wxCoord* w, wxCoord* h,
 934                        wxCoord* descent = NULL,
 935                        wxCoord* externalLeading = NULL,
 936                        const wxFont* font = NULL) const;
 937
 938     /**
 939         @overload
 940
 941
 942         @beginWxPerlOnly
 943         Not supported by wxPerl.
 944         @endWxPerlOnly
 945     */
 946     wxSize GetTextExtent(const wxString& string) const;
 947
 948     //@}
 949
 950
 951     /**
 952         @name Text properties functions
 953     */
 954     //@{
 955
 956     /**
 957         Returns the current background mode: @c wxSOLID or @c wxTRANSPARENT.
 958
 959         @see SetBackgroundMode()
 960     */
 961     int GetBackgroundMode() const;
 962
 963     /**
 964         Gets the current font.
 965
 966         Notice that even although each device context object has some default font
 967         after creation, this method would return a ::wxNullFont initially and only
 968         after calling SetFont() a valid font is returned.
 969     */
 970     const wxFont& GetFont() const;
 971
 972     /**
 973         Gets the current layout direction of the device context. On platforms
 974         where RTL layout is supported, the return value will either be
 975         @c wxLayout_LeftToRight or @c wxLayout_RightToLeft. If RTL layout is
 976         not supported, the return value will be @c wxLayout_Default.
 977
 978         @see SetLayoutDirection()
 979     */
 980     wxLayoutDirection GetLayoutDirection() const;
 981
 982     /**
 983         Gets the current text background colour.
 984
 985         @see SetTextBackground()
 986     */
 987     const wxColour& GetTextBackground() const;
 988
 989     /**
 990         Gets the current text foreground colour.
 991
 992         @see SetTextForeground()
 993     */
 994     const wxColour& GetTextForeground() const;
 995
 996     /**
 997         @a mode may be one of @c wxSOLID and @c wxTRANSPARENT.
 998
 999         This setting determines whether text will be drawn with a background
1000         colour or not.
1001     */
1002     void SetBackgroundMode(int mode);
1003
1004     /**
1005         Sets the current font for the DC.
1006
1007         If the argument is ::wxNullFont (or another invalid font; see wxFont::IsOk),
1008         the current font is selected out of the device context (leaving wxDC without
1009         any valid font), allowing the current font to be destroyed safely.
1010
1011         @see wxFont
1012     */
1013     void SetFont(const wxFont& font);
1014
1015     /**
1016         Sets the current text background colour for the DC.
1017     */
1018     void SetTextBackground(const wxColour& colour);
1019
1020     /**
1021         Sets the current text foreground colour for the DC.
1022
1023         @see wxMemoryDC for the interpretation of colours when drawing into a
1024              monochrome bitmap.
1025     */
1026     void SetTextForeground(const wxColour& colour);
1027
1028     /**
1029         Sets the current layout direction for the device context.
1030
1031         @param dir
1032            May be either @c wxLayout_Default, @c wxLayout_LeftToRight or
1033            @c wxLayout_RightToLeft.
1034
1035         @see GetLayoutDirection()
1036     */
1037     void SetLayoutDirection(wxLayoutDirection dir);
1038
1039     //@}
1040
1041
1042     /**
1043         @name Bounding box functions
1044     */
1045     //@{
1046
1047     /**
1048         Adds the specified point to the bounding box which can be retrieved
1049         with MinX(), MaxX() and MinY(), MaxY() functions.
1050
1051         @see ResetBoundingBox()
1052     */
1053     void CalcBoundingBox(wxCoord x, wxCoord y);
1054
1055     /**
1056         Gets the maximum horizontal extent used in drawing commands so far.
1057     */
1058     wxCoord MaxX() const;
1059
1060     /**
1061         Gets the maximum vertical extent used in drawing commands so far.
1062     */
1063     wxCoord MaxY() const;
1064
1065     /**
1066         Gets the minimum horizontal extent used in drawing commands so far.
1067     */
1068     wxCoord MinX() const;
1069
1070     /**
1071         Gets the minimum vertical extent used in drawing commands so far.
1072     */
1073     wxCoord MinY() const;
1074
1075     /**
1076         Resets the bounding box: after a call to this function, the bounding
1077         box doesn't contain anything.
1078
1079         @see CalcBoundingBox()
1080     */
1081     void ResetBoundingBox();
1082
1083     //@}
1084
1085
1086     /**
1087         @name Page and document start/end functions
1088     */
1089     //@{
1090
1091     /**
1092         Starts a document (only relevant when outputting to a printer).
1093         @a message is a message to show while printing.
1094     */
1095     bool StartDoc(const wxString& message);
1096
1097     /**
1098         Starts a document page (only relevant when outputting to a printer).
1099     */
1100     void StartPage();
1101
1102     /**
1103         Ends a document (only relevant when outputting to a printer).
1104     */
1105     void EndDoc();
1106
1107     /**
1108         Ends a document page (only relevant when outputting to a printer).
1109     */
1110     void EndPage();
1111
1112     //@}
1113
1114
1115     /**
1116         @name Bit-Block Transfer operations (blit)
1117     */
1118     //@{
1119
1120     /**
1121         Copy from a source DC to this DC, specifying the destination
1122         coordinates, size of area to copy, source DC, source coordinates,
1123         logical function, whether to use a bitmap mask, and mask source
1124         position.
1125
1126         @param xdest
1127             Destination device context x position.
1128         @param ydest
1129             Destination device context y position.
1130         @param width
1131             Width of source area to be copied.
1132         @param height
1133             Height of source area to be copied.
1134         @param source
1135             Source device context.
1136         @param xsrc
1137             Source device context x position.
1138         @param ysrc
1139             Source device context y position.
1140         @param logicalFunc
1141             Logical function to use, see SetLogicalFunction().
1142         @param useMask
1143             If @true, Blit does a transparent blit using the mask that is
1144             associated with the bitmap selected into the source device context.
1145             The Windows implementation does the following if MaskBlt cannot be
1146             used:
1147             <ol>
1148             <li>Creates a temporary bitmap and copies the destination area into
1149                 it.</li>
1150             <li>Copies the source area into the temporary bitmap using the
1151                 specified logical function.</li>
1152             <li>Sets the masked area in the temporary bitmap to BLACK by ANDing
1153                 the mask bitmap with the temp bitmap with the foreground colour
1154                 set to WHITE and the bg colour set to BLACK.</li>
1155             <li>Sets the unmasked area in the destination area to BLACK by
1156                 ANDing the mask bitmap with the destination area with the
1157                 foreground colour set to BLACK and the background colour set to
1158                 WHITE.</li>
1159             <li>ORs the temporary bitmap with the destination area.</li>
1160             <li>Deletes the temporary bitmap.</li>
1161             </ol>
1162             This sequence of operations ensures that the source's transparent
1163             area need not be black, and logical functions are supported.
1164             @n @b Note: on Windows, blitting with masks can be speeded up
1165             considerably by compiling wxWidgets with the wxUSE_DC_CACHEING option
1166             enabled. You can also influence whether MaskBlt or the explicit
1167             mask blitting code above is used, by using wxSystemOptions and
1168             setting the @c no-maskblt option to 1.
1169         @param xsrcMask
1170             Source x position on the mask. If both xsrcMask and ysrcMask are
1171             @c -1, xsrc and ysrc will be assumed for the mask source position.
1172             Currently only implemented on Windows.
1173         @param ysrcMask
1174             Source y position on the mask. If both xsrcMask and ysrcMask are
1175             @c -1, xsrc and ysrc will be assumed for the mask source position.
1176             Currently only implemented on Windows.
1177
1178         @remarks There is partial support for Blit() in wxPostScriptDC, under X.
1179
1180         @see StretchBlit(), wxMemoryDC, wxBitmap, wxMask
1181     */
1182     bool Blit(wxCoord xdest, wxCoord ydest, wxCoord width,
1183               wxCoord height, wxDC* source, wxCoord xsrc, wxCoord ysrc,
1184               wxRasterOperationMode logicalFunc = wxCOPY, bool useMask = false,
1185               wxCoord xsrcMask = wxDefaultCoord, wxCoord ysrcMask = wxDefaultCoord);
1186
1187     /**
1188         Copy from a source DC to this DC, specifying the destination
1189         coordinates, destination size, source DC, source coordinates, size of
1190         source area to copy, logical function, whether to use a bitmap mask,
1191         and mask source position.
1192
1193         @param xdest
1194             Destination device context x position.
1195         @param ydest
1196             Destination device context y position.
1197         @param dstWidth
1198             Width of destination area.
1199         @param dstHeight
1200             Height of destination area.
1201         @param source
1202             Source device context.
1203         @param xsrc
1204             Source device context x position.
1205         @param ysrc
1206             Source device context y position.
1207         @param srcWidth
1208             Width of source area to be copied.
1209         @param srcHeight
1210             Height of source area to be copied.
1211         @param logicalFunc
1212             Logical function to use, see SetLogicalFunction().
1213         @param useMask
1214             If @true, Blit does a transparent blit using the mask that is
1215             associated with the bitmap selected into the source device context.
1216             The Windows implementation does the following if MaskBlt cannot be
1217             used:
1218             <ol>
1219             <li>Creates a temporary bitmap and copies the destination area into
1220                 it.</li>
1221             <li>Copies the source area into the temporary bitmap using the
1222                 specified logical function.</li>
1223             <li>Sets the masked area in the temporary bitmap to BLACK by ANDing
1224                 the mask bitmap with the temp bitmap with the foreground colour
1225                 set to WHITE and the bg colour set to BLACK.</li>
1226             <li>Sets the unmasked area in the destination area to BLACK by
1227                 ANDing the mask bitmap with the destination area with the
1228                 foreground colour set to BLACK and the background colour set to
1229                 WHITE.</li>
1230             <li>ORs the temporary bitmap with the destination area.</li>
1231             <li>Deletes the temporary bitmap.</li>
1232             </ol>
1233             This sequence of operations ensures that the source's transparent
1234             area need not be black, and logical functions are supported.
1235             @n @b Note: on Windows, blitting with masks can be speeded up
1236             considerably by compiling wxWidgets with the wxUSE_DC_CACHEING option
1237             enabled. You can also influence whether MaskBlt or the explicit
1238             mask blitting code above is used, by using wxSystemOptions and
1239             setting the @c no-maskblt option to 1.
1240         @param xsrcMask
1241             Source x position on the mask. If both xsrcMask and ysrcMask are
1242             wxDefaultCoord, @a xsrc and @a ysrc will be assumed for the mask
1243             source position. Currently only implemented on Windows.
1244         @param ysrcMask
1245             Source y position on the mask. If both xsrcMask and ysrcMask are
1246             wxDefaultCoord, @a xsrc and @a ysrc will be assumed for the mask
1247             source position. Currently only implemented on Windows.
1248
1249         There is partial support for Blit() in wxPostScriptDC, under X.
1250
1251         StretchBlit() is only implemented under wxMAC and wxMSW.
1252
1253         See wxMemoryDC for typical usage.
1254
1255         @since 2.9.0
1256
1257         @see Blit(), wxMemoryDC, wxBitmap, wxMask
1258     */
1259     bool StretchBlit(wxCoord xdest, wxCoord ydest,
1260                      wxCoord dstWidth, wxCoord dstHeight,
1261                      wxDC* source, wxCoord xsrc, wxCoord ysrc,
1262                      wxCoord srcWidth, wxCoord srcHeight,
1263                      wxRasterOperationMode logicalFunc = wxCOPY,
1264                      bool useMask = false,
1265                      wxCoord xsrcMask = wxDefaultCoord,
1266                      wxCoord ysrcMask = wxDefaultCoord);
1267     //@}
1268
1269
1270     /**
1271         @name Background/foreground brush and pen
1272     */
1273     //@{
1274
1275     /**
1276         Gets the brush used for painting the background.
1277
1278         @see wxDC::SetBackground()
1279     */
1280     const wxBrush& GetBackground() const;
1281
1282     /**
1283         Gets the current brush.
1284
1285         @see wxDC::SetBrush()
1286     */
1287     const wxBrush& GetBrush() const;
1288
1289     /**
1290         Gets the current pen.
1291
1292         @see SetPen()
1293     */
1294     const wxPen& GetPen() const;
1295
1296     /**
1297         Sets the current background brush for the DC.
1298     */
1299     void SetBackground(const wxBrush& brush);
1300
1301     /**
1302         Sets the current brush for the DC.
1303
1304         If the argument is ::wxNullBrush (or another invalid brush; see wxBrush::IsOk),
1305         the current brush is selected out of the device context (leaving wxDC without
1306         any valid brush), allowing the current brush to be destroyed safely.
1307
1308         @see wxBrush, wxMemoryDC (for the interpretation of colours when
1309              drawing into a monochrome bitmap)
1310     */
1311     void SetBrush(const wxBrush& brush);
1312
1313     /**
1314         Sets the current pen for the DC.
1315
1316         If the argument is ::wxNullPen (or another invalid pen; see wxPen::IsOk),
1317         the current pen is selected out of the device context (leaving wxDC without any
1318         valid pen), allowing the current pen to be destroyed safely.
1319
1320         @see wxMemoryDC for the interpretation of colours when drawing into a
1321              monochrome bitmap.
1322     */
1323     void SetPen(const wxPen& pen);
1324
1325     //@}
1326
1327
1328     /**
1329         Copy attributes from another DC.
1330
1331         The copied attributes currently are:
1332             - Font
1333             - Text foreground and background colours
1334             - Background brush
1335             - Layout direction
1336
1337         @param dc
1338             A valid (i.e. its IsOk() must return @true) source device context.
1339      */
1340     void CopyAttributes(const wxDC& dc);
1341
1342     /**
1343         Returns the depth (number of bits/pixel) of this DC.
1344
1345         @see wxDisplayDepth()
1346     */
1347     int GetDepth() const;
1348
1349     /**
1350         Returns the current device origin.
1351
1352         @see SetDeviceOrigin()
1353     */
1354     wxPoint GetDeviceOrigin() const;
1355
1356     /**
1357         Gets the current logical function.
1358
1359         @see SetLogicalFunction()
1360     */
1361     wxRasterOperationMode GetLogicalFunction() const;
1362
1363     /**
1364         Gets the current mapping mode for the device context.
1365
1366         @see SetMapMode()
1367     */
1368     wxMappingMode GetMapMode() const;
1369
1370     /**
1371         Gets in @a colour the colour at the specified location. Not available
1372         for wxPostScriptDC or wxMetafileDC.
1373
1374         @note Setting a pixel can be done using DrawPoint().
1375
1376         @note This method shouldn't be used with wxPaintDC as accessing the DC
1377         while drawing can result in unexpected results, notably in wxGTK.
1378
1379         @beginWxPythonOnly
1380         The wxColour value is returned and is not required as a parameter.
1381         @endWxPythonOnly
1382     */
1383     bool GetPixel(wxCoord x, wxCoord y, wxColour* colour) const;
1384
1385     /**
1386         Returns the resolution of the device in pixels per inch.
1387     */
1388     wxSize GetPPI() const;
1389
1390     /**
1391         Gets the horizontal and vertical extent of this device context in @e device units.
1392         It can be used to scale graphics to fit the page.
1393
1394         For example, if @e maxX and @e maxY represent the maximum horizontal
1395         and vertical 'pixel' values used in your application, the following
1396         code will scale the graphic to fit on the printer page:
1397
1398         @code
1399         wxCoord w, h;
1400         dc.GetSize(&w, &h);
1401         double scaleX = (double)(maxX / w);
1402         double scaleY = (double)(maxY / h);
1403         dc.SetUserScale(min(scaleX, scaleY),min(scaleX, scaleY));
1404         @endcode
1405
1406         @beginWxPythonOnly
1407         In place of a single overloaded method name, wxPython implements the
1408         following methods:
1409         - GetSize() - Returns a wxSize.
1410         - GetSizeWH() - Returns a 2-tuple (width, height).
1411         @endWxPythonOnly
1412
1413         @beginWxPerlOnly
1414         In wxPerl there are two methods instead of a single overloaded
1415         method:
1416         - GetSize(): returns a Wx::Size object.
1417         - GetSizeWH(): returns a 2-element list (width, height).
1418         @endWxPerlOnly
1419     */
1420     void GetSize(wxCoord* width, wxCoord* height) const;
1421
1422     /**
1423         @overload
1424     */
1425     wxSize GetSize() const;
1426
1427     /**
1428         Returns the horizontal and vertical resolution in millimetres.
1429     */
1430     void GetSizeMM(wxCoord* width, wxCoord* height) const;
1431
1432     /**
1433         @overload
1434     */
1435     wxSize GetSizeMM() const;
1436
1437     /**
1438         Gets the current user scale factor.
1439
1440         @beginWxPerlOnly
1441         In wxPerl this method takes no arguments and return a two
1442         element array (x, y).
1443         @endWxPerlOnly
1444
1445         @see SetUserScale()
1446     */
1447     void GetUserScale(double* x, double* y) const;
1448
1449     /**
1450         Returns @true if the DC is ok to use.
1451     */
1452     bool IsOk() const;
1453
1454     /**
1455         Sets the x and y axis orientation (i.e., the direction from lowest to
1456         highest values on the axis). The default orientation is x axis from
1457         left to right and y axis from top down.
1458
1459         @param xLeftRight
1460             True to set the x axis orientation to the natural left to right
1461             orientation, @false to invert it.
1462         @param yBottomUp
1463             True to set the y axis orientation to the natural bottom up
1464             orientation, @false to invert it.
1465     */
1466     void SetAxisOrientation(bool xLeftRight, bool yBottomUp);
1467
1468     /**
1469         Sets the device origin (i.e., the origin in pixels after scaling has
1470         been applied). This function may be useful in Windows printing
1471         operations for placing a graphic on a page.
1472     */
1473     void SetDeviceOrigin(wxCoord x, wxCoord y);
1474
1475     /**
1476         Sets the current logical function for the device context.
1477         It determines how a @e source pixel (from a pen or brush colour, or source
1478         device context if using Blit()) combines with a @e destination pixel in
1479         the current device context.
1480         Text drawing is not affected by this function.
1481
1482         See ::wxRasterOperationMode enumeration values for more info.
1483
1484         The default is @c wxCOPY, which simply draws with the current colour.
1485         The others combine the current colour and the background using a logical
1486         operation. @c wxINVERT is commonly used for drawing rubber bands or moving
1487         outlines, since drawing twice reverts to the original colour.
1488     */
1489     void SetLogicalFunction(wxRasterOperationMode function);
1490
1491     /**
1492         The mapping mode of the device context defines the unit of measurement
1493         used to convert @e logical units to @e device units.
1494
1495         Note that in X, text drawing isn't handled consistently with the mapping mode;
1496         a font is always specified in point size. However, setting the user scale (see
1497         SetUserScale()) scales the text appropriately. In Windows, scalable
1498         TrueType fonts are always used; in X, results depend on availability of
1499         fonts, but usually a reasonable match is found.
1500
1501         The coordinate origin is always at the top left of the screen/printer.
1502
1503         Drawing to a Windows printer device context uses the current mapping
1504         mode, but mapping mode is currently ignored for PostScript output.
1505     */
1506     void SetMapMode(wxMappingMode mode);
1507
1508     /**
1509         If this is a window DC or memory DC, assigns the given palette to the
1510         window or bitmap associated with the DC. If the argument is
1511         ::wxNullPalette, the current palette is selected out of the device
1512         context, and the original palette restored.
1513
1514         @see wxPalette
1515     */
1516     void SetPalette(const wxPalette& palette);
1517
1518     /**
1519         Sets the user scaling factor, useful for applications which require
1520         'zooming'.
1521     */
1522     void SetUserScale(double xScale, double yScale);
1523
1524
1525     /**
1526         @name Transformation matrix
1527
1528         See the notes about the availability of these functions in the class
1529         documentation.
1530     */
1531     //@{
1532
1533     /**
1534         Check if the use of transformation matrix is supported by the current
1535         system.
1536
1537         Currently this function always returns @false for non-MSW platforms and
1538         may return @false for old (Windows 9x/ME) Windows systems. Normally
1539         support for the transformation matrix is always available in any
1540         relatively recent Windows versions.
1541
1542         @since 2.9.2
1543     */
1544     bool CanUseTransformMatrix() const;
1545
1546     /**
1547         Set the transformation matrix.
1548
1549         If transformation matrix is supported on the current system, the
1550         specified @a matrix will be used to transform between wxDC and physical
1551         coordinates. Otherwise the function returns @false and doesn't change
1552         the coordinate mapping.
1553
1554         @since 2.9.2
1555     */
1556     bool SetTransformMatrix(const wxAffineMatrix2D& matrix);
1557
1558     /**
1559         Return the transformation matrix used by this device context.
1560
1561         By default the transformation matrix is the identity matrix.
1562
1563         @since 2.9.2
1564     */
1565     wxAffineMatrix2D GetTransformMatrix() const;
1566
1567     /**
1568         Revert the transformation matrix to identity matrix.
1569
1570         @since 2.9.2
1571     */
1572     void ResetTransformMatrix();
1573
1574     //@}
1575
1576
1577     void SetLogicalScale(double x, double y);
1578     void GetLogicalScale(double *x, double *y) const;
1579     void SetLogicalOrigin(wxCoord x, wxCoord y);
1580     void GetLogicalOrigin(wxCoord *x, wxCoord *y) const;
1581     wxPoint GetLogicalOrigin() const;
1582
1583 };
1584
1585
1586
1587 /**
1588     @class wxDCClipper
1589
1590     wxDCClipper is a small helper class for setting a clipping region on a wxDC
1591     and unsetting it automatically. An object of wxDCClipper class is typically
1592     created on the stack so that it is automatically destroyed when the object
1593     goes out of scope. A typical usage example:
1594
1595     @code
1596     void MyFunction(wxDC& dc)
1597     {
1598         wxDCClipper clip(dc, rect);
1599         // ... drawing functions here are affected by clipping rect ...
1600     }
1601
1602     void OtherFunction()
1603     {
1604         wxDC dc;
1605         MyFunction(dc);
1606         // ... drawing functions here are not affected by clipping rect ...
1607     }
1608     @endcode
1609
1610     @library{wxcore}
1611     @category{gdi}
1612
1613     @see wxDC::SetClippingRegion(), wxDCFontChanger, wxDCTextColourChanger, wxDCPenChanger,
1614          wxDCBrushChanger
1615 */
1616 class wxDCClipper
1617 {
1618 public:
1619     //@{
1620     /**
1621         Sets the clipping region to the specified region/coordinates.
1622
1623         The clipping region is automatically unset when this object is destroyed.
1624     */
1625     wxDCClipper(wxDC& dc, const wxRegion& region);
1626     wxDCClipper(wxDC& dc, const wxRect& rect);
1627     wxDCClipper(wxDC& dc, wxCoord x, wxCoord y, wxCoord w, wxCoord h);
1628     //@}
1629
1630     /**
1631         Destroys the clipping region associated with the DC passed to the ctor.
1632     */
1633     ~wxDCClipper();
1634 };
1635
1636
1637 /**
1638     @class wxDCBrushChanger
1639
1640     wxDCBrushChanger is a small helper class for setting a brush on a wxDC
1641     and unsetting it automatically in the destructor, restoring the previous one.
1642
1643     @library{wxcore}
1644     @category{gdi}
1645
1646     @see wxDC::SetBrush(), wxDCFontChanger, wxDCTextColourChanger, wxDCPenChanger,
1647          wxDCClipper
1648 */
1649 class wxDCBrushChanger
1650 {
1651 public:
1652     /**
1653         Sets @a brush on the given @a dc, storing the old one.
1654
1655         @param dc
1656             The DC where the brush must be temporary set.
1657         @param brush
1658             The brush to set.
1659     */
1660     wxDCBrushChanger(wxDC& dc, const wxBrush& brush);
1661
1662     /**
1663         Restores the brush originally selected in the DC passed to the ctor.
1664     */
1665     ~wxDCBrushChanger();
1666 };
1667
1668
1669 /**
1670     @class wxDCPenChanger
1671
1672     wxDCPenChanger is a small helper class for setting a pen on a wxDC
1673     and unsetting it automatically in the destructor, restoring the previous one.
1674
1675     @library{wxcore}
1676     @category{gdi}
1677
1678     @see wxDC::SetPen(), wxDCFontChanger, wxDCTextColourChanger, wxDCBrushChanger,
1679          wxDCClipper
1680 */
1681 class wxDCPenChanger
1682 {
1683 public:
1684     /**
1685         Sets @a pen on the given @a dc, storing the old one.
1686
1687         @param dc
1688             The DC where the pen must be temporary set.
1689         @param pen
1690             The pen to set.
1691     */
1692     wxDCPenChanger(wxDC& dc, const wxPen& pen);
1693
1694     /**
1695         Restores the pen originally selected in the DC passed to the ctor.
1696     */
1697     ~wxDCPenChanger();
1698 };
1699
1700
1701
1702 /**
1703     @class wxDCTextColourChanger
1704
1705     wxDCTextColourChanger is a small helper class for setting a foreground
1706     text colour on a wxDC and unsetting it automatically in the destructor,
1707     restoring the previous one.
1708
1709     @library{wxcore}
1710     @category{gdi}
1711
1712     @see wxDC::SetTextForeground(), wxDCFontChanger, wxDCPenChanger, wxDCBrushChanger,
1713          wxDCClipper
1714 */
1715 class wxDCTextColourChanger
1716 {
1717 public:
1718     /**
1719         Trivial constructor not changing anything.
1720
1721         This constructor is useful if you don't know beforehand if the colour
1722         needs to be changed or not. It simply creates the object which won't do
1723         anything in its destructor unless Set() is called -- in which case it
1724         would reset the previous colour.
1725      */
1726     wxDCTextColourChanger(wxDC& dc);
1727
1728     /**
1729         Sets @a col on the given @a dc, storing the old one.
1730
1731         @param dc
1732             The DC where the colour must be temporary set.
1733         @param col
1734             The colour to set.
1735     */
1736     wxDCTextColourChanger(wxDC& dc, const wxColour& col);
1737
1738     /**
1739         Set the colour to use.
1740
1741         This method is meant to be called once only and only on the objects
1742         created with the constructor overload not taking wxColour argument and
1743         has the same effect as the other constructor, i.e. sets the colour to
1744         the given @a col and ensures that the old value is restored when this
1745         object is destroyed.
1746      */
1747     void Set(const wxColour& col);
1748
1749     /**
1750         Restores the colour originally selected in the DC passed to the ctor.
1751     */
1752     ~wxDCTextColourChanger();
1753 };
1754
1755
1756
1757 /**
1758     @class wxDCFontChanger
1759
1760     wxDCFontChanger is a small helper class for setting a font on a wxDC and
1761     unsetting it automatically in the destructor, restoring the previous one.
1762
1763     @since 2.9.0
1764
1765     @library{wxcore}
1766     @category{gdi}
1767
1768     @see wxDC::SetFont(), wxDCTextColourChanger, wxDCPenChanger, wxDCBrushChanger,
1769          wxDCClipper
1770 */
1771 class wxDCFontChanger
1772 {
1773 public:
1774     /**
1775         Trivial constructor not changing anything.
1776
1777         This constructor is useful if you don't know beforehand if the font
1778         needs to be changed or not. It simply creates the object which won't do
1779         anything in its destructor unless Set() is called -- in which case it
1780         would reset the previous font.
1781
1782         @since 2.9.1
1783      */
1784     wxDCFontChanger(wxDC& dc);
1785
1786     /**
1787         Sets @a font on the given @a dc, storing the old one.
1788
1789         @param dc
1790             The DC where the font must be temporary set.
1791         @param font
1792             The font to set.
1793     */
1794     wxDCFontChanger(wxDC& dc, const wxFont& font);
1795
1796     /**
1797         Set the font to use.
1798
1799         This method is meant to be called once only and only on the objects
1800         created with the constructor overload not taking wxColour argument and
1801         has the same effect as the other constructor, i.e. sets the font to
1802         the given @a font and ensures that the old value is restored when this
1803         object is destroyed.
1804      */
1805     void Set(const wxFont& font);
1806
1807     /**
1808         Restores the font originally selected in the DC passed to the ctor.
1809     */
1810     ~wxDCFontChanger();
1811 };
1812