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         @beginWxPerlOnly
 413         Not supported by wxPerl.
 414         @endWxPerlOnly
 415     */
 416     void DrawLines(int n, wxPoint points[], wxCoord xoffset = 0,
 417                    wxCoord yoffset = 0);
 418     /**
 419         This method uses a list of wxPoints, adding the optional offset
 420         coordinate. The programmer is responsible for deleting the list of
 421         points.
 422
 423         @beginWxPerlOnly
 424         The wxPerl version of this method accepts
 425         as its first parameter a reference to an array
 426         of wxPoint objects.
 427         @endWxPerlOnly
 428     */
 429     void DrawLines(const wxPointList* points,
 430                    wxCoord xoffset = 0, wxCoord yoffset = 0);
 431
 432     /**
 433         Draws a point using the color of the current pen. Note that the other
 434         properties of the pen are not used, such as width.
 435     */
 436     void DrawPoint(wxCoord x, wxCoord y);
 437
 438     /**
 439         @overload
 440     */
 441     void DrawPoint(const wxPoint& pt);
 442
 443     /**
 444         Draws a filled polygon using an array of points of size @a n, adding
 445         the optional offset coordinate. The first and last points are
 446         automatically closed.
 447
 448         The last argument specifies the fill rule: @b wxODDEVEN_RULE (the
 449         default) or @b wxWINDING_RULE.
 450
 451         The current pen is used for drawing the outline, and the current brush
 452         for filling the shape. Using a transparent brush suppresses filling.
 453
 454         @beginWxPerlOnly
 455         Not supported by wxPerl.
 456         @endWxPerlOnly
 457     */
 458     void DrawPolygon(int n, wxPoint points[], wxCoord xoffset = 0,
 459                      wxCoord yoffset = 0,
 460                      wxPolygonFillMode fill_style = wxODDEVEN_RULE);
 461     /**
 462         This method draws a filled polygon using a list of wxPoints, adding the
 463         optional offset coordinate. The first and last points are automatically
 464         closed.
 465
 466         The last argument specifies the fill rule: @b wxODDEVEN_RULE (the
 467         default) or @b wxWINDING_RULE.
 468
 469         The current pen is used for drawing the outline, and the current brush
 470         for filling the shape. Using a transparent brush suppresses filling.
 471
 472         The programmer is responsible for deleting the list of points.
 473
 474         @beginWxPerlOnly
 475         The wxPerl version of this method accepts
 476         as its first parameter a reference to an array
 477         of wxPoint objects.
 478         @endWxPerlOnly
 479     */
 480     void DrawPolygon(const wxPointList* points,
 481                      wxCoord xoffset = 0, wxCoord yoffset = 0,
 482                      wxPolygonFillMode fill_style = wxODDEVEN_RULE);
 483
 484     /**
 485         Draws two or more filled polygons using an array of @a points, adding
 486         the optional offset coordinates.
 487
 488         Notice that for the platforms providing a native implementation of this
 489         function (Windows and PostScript-based wxDC currently), this is more
 490         efficient than using DrawPolygon() in a loop.
 491
 492         @a n specifies the number of polygons to draw, the array @e count of
 493         size @a n specifies the number of points in each of the polygons in the
 494         @a points array.
 495
 496         The last argument specifies the fill rule: @b wxODDEVEN_RULE (the
 497         default) or @b wxWINDING_RULE.
 498
 499         The current pen is used for drawing the outline, and the current brush
 500         for filling the shape. Using a transparent brush suppresses filling.
 501
 502         The polygons maybe disjoint or overlapping. Each polygon specified in a
 503         call to DrawPolyPolygon() must be closed. Unlike polygons created by
 504         the DrawPolygon() member function, the polygons created by this
 505         method are not closed automatically.
 506     */
 507     void DrawPolyPolygon(int n, int count[], wxPoint points[],
 508                          wxCoord xoffset = 0, wxCoord yoffset = 0,
 509                          wxPolygonFillMode fill_style = wxODDEVEN_RULE);
 510
 511     /**
 512         Draws a rectangle with the given top left corner, and with the given
 513         size.  The current pen is used for the outline and the current brush
 514         for filling the shape.
 515     */
 516     void DrawRectangle(wxCoord x, wxCoord y, wxCoord width, wxCoord height);
 517
 518     /**
 519         @overload
 520     */
 521     void DrawRectangle(const wxPoint& pt, const wxSize& sz);
 522
 523     /**
 524         @overload
 525     */
 526     void DrawRectangle(const wxRect& rect);
 527
 528     /**
 529         Draws the text rotated by @a angle degrees
 530         (positive angles are counterclockwise; the full angle is 360 degrees).
 531
 532         @note Under Win9x only TrueType fonts can be drawn by this function. In
 533               particular, a font different from @c wxNORMAL_FONT should be used
 534               as the latter is not a TrueType font. @c wxSWISS_FONT is an
 535               example of a font which is.
 536
 537         @see DrawText()
 538     */
 539     void DrawRotatedText(const wxString& text, wxCoord x, wxCoord y,
 540                          double angle);
 541
 542     /**
 543         @overload
 544     */
 545     void DrawRotatedText(const wxString& text, const wxPoint& point,
 546                          double angle);
 547
 548     /**
 549         Draws a rectangle with the given top left corner, and with the given
 550         size. The corners are quarter-circles using the given radius. The
 551         current pen is used for the outline and the current brush for filling
 552         the shape.
 553
 554         If @a radius is positive, the value is assumed to be the radius of the
 555         rounded corner. If @a radius is negative, the absolute value is assumed
 556         to be the @e proportion of the smallest dimension of the rectangle.
 557         This means that the corner can be a sensible size relative to the size
 558         of the rectangle, and also avoids the strange effects X produces when
 559         the corners are too big for the rectangle.
 560     */
 561     void DrawRoundedRectangle(wxCoord x, wxCoord y, wxCoord width,
 562                               wxCoord height, double radius);
 563
 564     /**
 565         @overload
 566     */
 567     void DrawRoundedRectangle(const wxPoint& pt, const wxSize& sz,
 568                               double radius);
 569
 570     /**
 571         @overload
 572     */
 573     void DrawRoundedRectangle(const wxRect& rect, double radius);
 574
 575     /**
 576         Draws a spline between all given points using the current pen.
 577
 578         @beginWxPerlOnly
 579         Not supported by wxPerl.
 580         @endWxPerlOnly
 581     */
 582     void DrawSpline(int n, wxPoint points[]);
 583
 584     /**
 585         @overload
 586
 587
 588         @beginWxPerlOnly
 589         The wxPerl version of this method accepts
 590         as its first parameter a reference to an array
 591         of wxPoint objects.
 592         @endWxPerlOnly
 593     */
 594     void DrawSpline(const wxPointList* points);
 595
 596     /**
 597         @overload
 598
 599
 600         @beginWxPerlOnly
 601         Not supported by wxPerl.
 602         @endWxPerlOnly
 603     */
 604     void DrawSpline(wxCoord x1, wxCoord y1, wxCoord x2, wxCoord y2,
 605                     wxCoord x3, wxCoord y3);
 606
 607     /**
 608         Draws a text string at the specified point, using the current text
 609         font, and the current text foreground and background colours.
 610
 611         The coordinates refer to the top-left corner of the rectangle bounding
 612         the string. See GetTextExtent() for how to get the dimensions of a text
 613         string, which can be used to position the text more precisely and
 614         DrawLabel() if you need to align the string differently.
 615
 616         Starting from wxWidgets 2.9.2 @a text parameter can be a multi-line
 617         string, i.e. contain new line characters, and will be rendered
 618         correctly.
 619
 620         @note The current @ref GetLogicalFunction() "logical function" is
 621               ignored by this function.
 622     */
 623     void DrawText(const wxString& text, wxCoord x, wxCoord y);
 624
 625     /**
 626         @overload
 627     */
 628     void DrawText(const wxString& text, const wxPoint& pt);
 629
 630     /**
 631         Fill the area specified by rect with a radial gradient, starting from
 632         @a initialColour at the centre of the circle and fading to
 633         @a destColour on the circle outside.
 634
 635         The circle is placed at the centre of @a rect.
 636
 637         @note Currently this function is very slow, don't use it for real-time
 638               drawing.
 639     */
 640     void GradientFillConcentric(const wxRect& rect,
 641                                 const wxColour& initialColour,
 642                                 const wxColour& destColour);
 643
 644     /**
 645         Fill the area specified by rect with a radial gradient, starting from
 646         @a initialColour at the centre of the circle and fading to
 647         @a destColour on the circle outside.
 648
 649         @a circleCenter are the relative coordinates of centre of the circle in
 650         the specified @a rect.
 651
 652         @note Currently this function is very slow, don't use it for real-time
 653               drawing.
 654     */
 655     void GradientFillConcentric(const wxRect& rect,
 656                                 const wxColour& initialColour,
 657                                 const wxColour& destColour,
 658                                 const wxPoint& circleCenter);
 659
 660     /**
 661         Fill the area specified by @a rect with a linear gradient, starting
 662         from @a initialColour and eventually fading to @e destColour.
 663
 664         The @a nDirection specifies the direction of the colour change, default is
 665         to use @a initialColour on the left part of the rectangle and
 666         @a destColour on the right one.
 667     */
 668     void GradientFillLinear(const wxRect& rect, const wxColour& initialColour,
 669                             const wxColour& destColour,
 670                             wxDirection nDirection = wxRIGHT);
 671
 672     /**
 673         Flood fills the device context starting from the given point, using
 674         the current brush colour, and using a style:
 675
 676         - wxFLOOD_SURFACE: The flooding occurs until a colour other than the
 677           given colour is encountered.
 678         - wxFLOOD_BORDER: The area to be flooded is bounded by the given
 679           colour.
 680
 681         @return @false if the operation failed.
 682
 683         @note The present implementation for non-Windows platforms may fail to
 684               find colour borders if the pixels do not match the colour
 685               exactly. However the function will still return @true.
 686
 687         @note This method shouldn't be used with wxPaintDC under non-Windows
 688               platforms as it uses GetPixel() internally and this may give
 689               wrong results, notably in wxGTK. If you need to flood fill
 690               wxPaintDC, create a temporary wxMemoryDC, flood fill it and then
 691               blit it to, or draw as a bitmap on, wxPaintDC. See the example of
 692               doing this in the drawing sample and wxBufferedPaintDC class.
 693     */
 694     bool FloodFill(wxCoord x, wxCoord y, const wxColour& colour,
 695                    wxFloodFillStyle style = wxFLOOD_SURFACE);
 696
 697     /**
 698         @overload
 699     */
 700     bool FloodFill(const wxPoint& pt, const wxColour& col,
 701                    wxFloodFillStyle style = wxFLOOD_SURFACE);
 702
 703     /**
 704         Displays a cross hair using the current pen. This is a vertical and
 705         horizontal line the height and width of the window, centred on the
 706         given point.
 707     */
 708     void CrossHair(wxCoord x, wxCoord y);
 709
 710     /**
 711         @overload
 712     */
 713     void CrossHair(const wxPoint& pt);
 714
 715     //@}
 716
 717
 718     /**
 719         @name Clipping region functions
 720     */
 721     //@{
 722
 723     /**
 724         Destroys the current clipping region so that none of the DC is clipped.
 725
 726         @see SetClippingRegion()
 727     */
 728     void DestroyClippingRegion();
 729
 730     /**
 731         Gets the rectangle surrounding the current clipping region.
 732     */
 733     void GetClippingBox(wxCoord *x, wxCoord *y, wxCoord *width, wxCoord *height) const;
 734
 735     /**
 736         Sets the clipping region for this device context to the intersection of
 737         the given region described by the parameters of this method and the
 738         previously set clipping region.
 739
 740         The clipping region is an area to which drawing is restricted. Possible
 741         uses for the clipping region are for clipping text or for speeding up
 742         window redraws when only a known area of the screen is damaged.
 743
 744         Notice that you need to call DestroyClippingRegion() if you want to set
 745         the clipping region exactly to the region specified.
 746
 747         Also note that if the clipping region is empty, any previously set
 748         clipping region is destroyed, i.e. it is equivalent to calling
 749         DestroyClippingRegion(), and not to clipping out all drawing on the DC
 750         as might be expected.
 751
 752         @see DestroyClippingRegion(), wxRegion
 753     */
 754     void SetClippingRegion(wxCoord x, wxCoord y, wxCoord width, wxCoord height);
 755
 756     /**
 757         @overload
 758     */
 759     void SetClippingRegion(const wxPoint& pt, const wxSize& sz);
 760
 761     /**
 762         @overload
 763     */
 764     void SetClippingRegion(const wxRect& rect);
 765
 766     /**
 767         Sets the clipping region for this device context.
 768
 769         Unlike SetClippingRegion(), this function works with physical
 770         coordinates and not with the logical ones.
 771      */
 772     void SetDeviceClippingRegion(const wxRegion& region);
 773
 774     //@}
 775
 776
 777     /**
 778         @name Text/character extent functions
 779     */
 780     //@{
 781
 782     /**
 783         Gets the character height of the currently set font.
 784     */
 785     wxCoord GetCharHeight() const;
 786
 787     /**
 788         Gets the average character width of the currently set font.
 789     */
 790     wxCoord GetCharWidth() const;
 791
 792     /**
 793         Returns the various font characteristics.
 794
 795         This method allows to retrieve some of the font characteristics not
 796         returned by GetTextExtent(), notably internal leading and average
 797         character width.
 798
 799         Currently this method returns correct results only under wxMSW, in the
 800         other ports the internal leading will always be 0 and the average
 801         character width will be computed as the width of the character 'x'.
 802
 803         @since 2.9.2
 804      */
 805     wxFontMetrics GetFontMetrics() const;
 806
 807     /**
 808         Gets the dimensions of the string using the currently selected font.
 809         @a string is the text string to measure, @e heightLine, if non @NULL,
 810         is where to store the height of a single line.
 811
 812         The text extent is set in the given @a w and @a h pointers.
 813
 814         If the optional parameter @a font is specified and valid, then it is
 815         used for the text extent calculation, otherwise the currently selected
 816         font is used.
 817
 818         @note This function works with both single-line and multi-line strings.
 819
 820         @beginWxPerlOnly
 821         In wxPerl this method is implemented as
 822         GetMultiLineTextExtent(string, font = undef) returning a
 823         3-element list (width, height, line_height)
 824         @endWxPerlOnly
 825
 826         @see wxFont, SetFont(), GetPartialTextExtents(), GetTextExtent()
 827     */
 828     void GetMultiLineTextExtent(const wxString& string, wxCoord* w,
 829                                 wxCoord* h,
 830                                 wxCoord* heightLine = NULL,
 831                                 const wxFont* font = NULL) const;
 832     /**
 833         Gets the dimensions of the string using the currently selected font.
 834         @a string is the text string to measure, @e heightLine, if non @NULL,
 835         is where to store the height of a single line.
 836
 837         @return The text extent as a wxSize object.
 838
 839         @note This function works with both single-line and multi-line strings.
 840
 841         @beginWxPerlOnly
 842         Not supported by wxPerl.
 843         @endWxPerlOnly
 844
 845         @see wxFont, SetFont(), GetPartialTextExtents(), GetTextExtent()
 846     */
 847     wxSize GetMultiLineTextExtent(const wxString& string) const;
 848
 849     /**
 850         Fills the @a widths array with the widths from the beginning of @a text
 851         to the corresponding character of @a text. The generic version simply
 852         builds a running total of the widths of each character using
 853         GetTextExtent(), however if the various platforms have a native API
 854         function that is faster or more accurate than the generic
 855         implementation then it should be used instead.
 856
 857         @beginWxPerlOnly
 858         In wxPerl this method only takes the @a text parameter and
 859         returns the widths as a list of integers.
 860         @endWxPerlOnly
 861
 862         @see GetMultiLineTextExtent(), GetTextExtent()
 863     */
 864     bool GetPartialTextExtents(const wxString& text,
 865                                wxArrayInt& widths) const;
 866
 867     /**
 868         Gets the dimensions of the string using the currently selected font.
 869         @a string is the text string to measure, @a descent is the dimension
 870         from the baseline of the font to the bottom of the descender, and
 871         @a externalLeading is any extra vertical space added to the font by the
 872         font designer (usually is zero).
 873
 874         The text extent is returned in @a w and @a h pointers or as a wxSize
 875         object depending on which version of this function is used.
 876
 877         If the optional parameter @a font is specified and valid, then it is
 878         used for the text extent calculation. Otherwise the currently selected
 879         font is.
 880
 881         @note This function only works with single-line strings.
 882
 883         @beginWxPerlOnly
 884         In wxPerl this method is implemented as GetTextExtent(string,
 885         font = undef) returning a 4-element list (width, height,
 886         descent, externalLeading)
 887         @endWxPerlOnly
 888
 889         @see wxFont, SetFont(), GetPartialTextExtents(),
 890              GetMultiLineTextExtent()
 891     */
 892     void GetTextExtent(const wxString& string, wxCoord* w, wxCoord* h,
 893                        wxCoord* descent = NULL,
 894                        wxCoord* externalLeading = NULL,
 895                        const wxFont* font = NULL) const;
 896
 897     /**
 898         @overload
 899
 900
 901         @beginWxPerlOnly
 902         Not supported by wxPerl.
 903         @endWxPerlOnly
 904     */
 905     wxSize GetTextExtent(const wxString& string) const;
 906
 907     //@}
 908
 909
 910     /**
 911         @name Text properties functions
 912     */
 913     //@{
 914
 915     /**
 916         Returns the current background mode: @c wxSOLID or @c wxTRANSPARENT.
 917
 918         @see SetBackgroundMode()
 919     */
 920     int GetBackgroundMode() const;
 921
 922     /**
 923         Gets the current font.
 924
 925         Notice that even although each device context object has some default font
 926         after creation, this method would return a ::wxNullFont initially and only
 927         after calling SetFont() a valid font is returned.
 928     */
 929     const wxFont& GetFont() const;
 930
 931     /**
 932         Gets the current layout direction of the device context. On platforms
 933         where RTL layout is supported, the return value will either be
 934         @c wxLayout_LeftToRight or @c wxLayout_RightToLeft. If RTL layout is
 935         not supported, the return value will be @c wxLayout_Default.
 936
 937         @see SetLayoutDirection()
 938     */
 939     wxLayoutDirection GetLayoutDirection() const;
 940
 941     /**
 942         Gets the current text background colour.
 943
 944         @see SetTextBackground()
 945     */
 946     const wxColour& GetTextBackground() const;
 947
 948     /**
 949         Gets the current text foreground colour.
 950
 951         @see SetTextForeground()
 952     */
 953     const wxColour& GetTextForeground() const;
 954
 955     /**
 956         @a mode may be one of @c wxSOLID and @c wxTRANSPARENT.
 957
 958         This setting determines whether text will be drawn with a background
 959         colour or not.
 960     */
 961     void SetBackgroundMode(int mode);
 962
 963     /**
 964         Sets the current font for the DC.
 965
 966         If the argument is ::wxNullFont (or another invalid font; see wxFont::IsOk),
 967         the current font is selected out of the device context (leaving wxDC without
 968         any valid font), allowing the current font to be destroyed safely.
 969
 970         @see wxFont
 971     */
 972     void SetFont(const wxFont& font);
 973
 974     /**
 975         Sets the current text background colour for the DC.
 976     */
 977     void SetTextBackground(const wxColour& colour);
 978
 979     /**
 980         Sets the current text foreground colour for the DC.
 981
 982         @see wxMemoryDC for the interpretation of colours when drawing into a
 983              monochrome bitmap.
 984     */
 985     void SetTextForeground(const wxColour& colour);
 986
 987     /**
 988         Sets the current layout direction for the device context.
 989
 990         @param dir
 991            May be either @c wxLayout_Default, @c wxLayout_LeftToRight or
 992            @c wxLayout_RightToLeft.
 993
 994         @see GetLayoutDirection()
 995     */
 996     void SetLayoutDirection(wxLayoutDirection dir);
 997
 998     //@}
 999
1000
1001     /**
1002         @name Bounding box functions
1003     */
1004     //@{
1005
1006     /**
1007         Adds the specified point to the bounding box which can be retrieved
1008         with MinX(), MaxX() and MinY(), MaxY() functions.
1009
1010         @see ResetBoundingBox()
1011     */
1012     void CalcBoundingBox(wxCoord x, wxCoord y);
1013
1014     /**
1015         Gets the maximum horizontal extent used in drawing commands so far.
1016     */
1017     wxCoord MaxX() const;
1018
1019     /**
1020         Gets the maximum vertical extent used in drawing commands so far.
1021     */
1022     wxCoord MaxY() const;
1023
1024     /**
1025         Gets the minimum horizontal extent used in drawing commands so far.
1026     */
1027     wxCoord MinX() const;
1028
1029     /**
1030         Gets the minimum vertical extent used in drawing commands so far.
1031     */
1032     wxCoord MinY() const;
1033
1034     /**
1035         Resets the bounding box: after a call to this function, the bounding
1036         box doesn't contain anything.
1037
1038         @see CalcBoundingBox()
1039     */
1040     void ResetBoundingBox();
1041
1042     //@}
1043
1044
1045     /**
1046         @name Page and document start/end functions
1047     */
1048     //@{
1049
1050     /**
1051         Starts a document (only relevant when outputting to a printer).
1052         @a message is a message to show while printing.
1053     */
1054     bool StartDoc(const wxString& message);
1055
1056     /**
1057         Starts a document page (only relevant when outputting to a printer).
1058     */
1059     void StartPage();
1060
1061     /**
1062         Ends a document (only relevant when outputting to a printer).
1063     */
1064     void EndDoc();
1065
1066     /**
1067         Ends a document page (only relevant when outputting to a printer).
1068     */
1069     void EndPage();
1070
1071     //@}
1072
1073
1074     /**
1075         @name Bit-Block Transfer operations (blit)
1076     */
1077     //@{
1078
1079     /**
1080         Copy from a source DC to this DC.
1081
1082         With this method you can specify the destination coordinates and the
1083         size of area to copy which will be the same for both the source and
1084         target DCs. If you need to apply scaling while copying, use
1085         StretchBlit().
1086
1087         Notice that source DC coordinates @a xsrc and @a ysrc are interpreted
1088         using the current source DC coordinate system, i.e. the scale, origin
1089         position and axis directions are taken into account when transforming
1090         them to physical (pixel) coordinates.
1091
1092         @param xdest
1093             Destination device context x position.
1094         @param ydest
1095             Destination device context y position.
1096         @param width
1097             Width of source area to be copied.
1098         @param height
1099             Height of source area to be copied.
1100         @param source
1101             Source device context.
1102         @param xsrc
1103             Source device context x position.
1104         @param ysrc
1105             Source device context y position.
1106         @param logicalFunc
1107             Logical function to use, see SetLogicalFunction().
1108         @param useMask
1109             If @true, Blit does a transparent blit using the mask that is
1110             associated with the bitmap selected into the source device context.
1111             The Windows implementation does the following if MaskBlt cannot be
1112             used:
1113             <ol>
1114             <li>Creates a temporary bitmap and copies the destination area into
1115                 it.</li>
1116             <li>Copies the source area into the temporary bitmap using the
1117                 specified logical function.</li>
1118             <li>Sets the masked area in the temporary bitmap to BLACK by ANDing
1119                 the mask bitmap with the temp bitmap with the foreground colour
1120                 set to WHITE and the bg colour set to BLACK.</li>
1121             <li>Sets the unmasked area in the destination area to BLACK by
1122                 ANDing the mask bitmap with the destination area with the
1123                 foreground colour set to BLACK and the background colour set to
1124                 WHITE.</li>
1125             <li>ORs the temporary bitmap with the destination area.</li>
1126             <li>Deletes the temporary bitmap.</li>
1127             </ol>
1128             This sequence of operations ensures that the source's transparent
1129             area need not be black, and logical functions are supported.
1130             @n @b Note: on Windows, blitting with masks can be speeded up
1131             considerably by compiling wxWidgets with the wxUSE_DC_CACHEING option
1132             enabled. You can also influence whether MaskBlt or the explicit
1133             mask blitting code above is used, by using wxSystemOptions and
1134             setting the @c no-maskblt option to 1.
1135         @param xsrcMask
1136             Source x position on the mask. If both xsrcMask and ysrcMask are
1137             @c -1, xsrc and ysrc will be assumed for the mask source position.
1138             Currently only implemented on Windows.
1139         @param ysrcMask
1140             Source y position on the mask. If both xsrcMask and ysrcMask are
1141             @c -1, xsrc and ysrc will be assumed for the mask source position.
1142             Currently only implemented on Windows.
1143
1144         @remarks There is partial support for Blit() in wxPostScriptDC, under X.
1145
1146         @see StretchBlit(), wxMemoryDC, wxBitmap, wxMask
1147     */
1148     bool Blit(wxCoord xdest, wxCoord ydest, wxCoord width,
1149               wxCoord height, wxDC* source, wxCoord xsrc, wxCoord ysrc,
1150               wxRasterOperationMode logicalFunc = wxCOPY, bool useMask = false,
1151               wxCoord xsrcMask = wxDefaultCoord, wxCoord ysrcMask = wxDefaultCoord);
1152
1153     /**
1154         Copy from a source DC to this DC possibly changing the scale.
1155
1156         Unlike Blit(), this method allows to specify different source and
1157         destination region sizes, meaning that it can stretch or shrink it
1158         while copying. The same can be achieved by changing the scale of the
1159         source or target DC but calling this method is simpler and can also be
1160         more efficient if the platform provides a native implementation of it.
1161
1162         The meaning of its other parameters is the same as with Blit(), in
1163         particular all source coordinates are interpreted using the source DC
1164         coordinate system, i.e. are affected by its scale, origin translation
1165         and axis direction.
1166
1167         @param xdest
1168             Destination device context x position.
1169         @param ydest
1170             Destination device context y position.
1171         @param dstWidth
1172             Width of destination area.
1173         @param dstHeight
1174             Height of destination area.
1175         @param source
1176             Source device context.
1177         @param xsrc
1178             Source device context x position.
1179         @param ysrc
1180             Source device context y position.
1181         @param srcWidth
1182             Width of source area to be copied.
1183         @param srcHeight
1184             Height of source area to be copied.
1185         @param logicalFunc
1186             Logical function to use, see SetLogicalFunction().
1187         @param useMask
1188             If @true, Blit does a transparent blit using the mask that is
1189             associated with the bitmap selected into the source device context.
1190             The Windows implementation does the following if MaskBlt cannot be
1191             used:
1192             <ol>
1193             <li>Creates a temporary bitmap and copies the destination area into
1194                 it.</li>
1195             <li>Copies the source area into the temporary bitmap using the
1196                 specified logical function.</li>
1197             <li>Sets the masked area in the temporary bitmap to BLACK by ANDing
1198                 the mask bitmap with the temp bitmap with the foreground colour
1199                 set to WHITE and the bg colour set to BLACK.</li>
1200             <li>Sets the unmasked area in the destination area to BLACK by
1201                 ANDing the mask bitmap with the destination area with the
1202                 foreground colour set to BLACK and the background colour set to
1203                 WHITE.</li>
1204             <li>ORs the temporary bitmap with the destination area.</li>
1205             <li>Deletes the temporary bitmap.</li>
1206             </ol>
1207             This sequence of operations ensures that the source's transparent
1208             area need not be black, and logical functions are supported.
1209             @n @b Note: on Windows, blitting with masks can be speeded up
1210             considerably by compiling wxWidgets with the wxUSE_DC_CACHEING option
1211             enabled. You can also influence whether MaskBlt or the explicit
1212             mask blitting code above is used, by using wxSystemOptions and
1213             setting the @c no-maskblt option to 1.
1214         @param xsrcMask
1215             Source x position on the mask. If both xsrcMask and ysrcMask are
1216             wxDefaultCoord, @a xsrc and @a ysrc will be assumed for the mask
1217             source position. Currently only implemented on Windows.
1218         @param ysrcMask
1219             Source y position on the mask. If both xsrcMask and ysrcMask are
1220             wxDefaultCoord, @a xsrc and @a ysrc will be assumed for the mask
1221             source position. Currently only implemented on Windows.
1222
1223         There is partial support for Blit() in wxPostScriptDC, under X.
1224
1225         See wxMemoryDC for typical usage.
1226
1227         @since 2.9.0
1228
1229         @see Blit(), wxMemoryDC, wxBitmap, wxMask
1230     */
1231     bool StretchBlit(wxCoord xdest, wxCoord ydest,
1232                      wxCoord dstWidth, wxCoord dstHeight,
1233                      wxDC* source, wxCoord xsrc, wxCoord ysrc,
1234                      wxCoord srcWidth, wxCoord srcHeight,
1235                      wxRasterOperationMode logicalFunc = wxCOPY,
1236                      bool useMask = false,
1237                      wxCoord xsrcMask = wxDefaultCoord,
1238                      wxCoord ysrcMask = wxDefaultCoord);
1239     //@}
1240
1241
1242     /**
1243         @name Background/foreground brush and pen
1244     */
1245     //@{
1246
1247     /**
1248         Gets the brush used for painting the background.
1249
1250         @see wxDC::SetBackground()
1251     */
1252     const wxBrush& GetBackground() const;
1253
1254     /**
1255         Gets the current brush.
1256
1257         @see wxDC::SetBrush()
1258     */
1259     const wxBrush& GetBrush() const;
1260
1261     /**
1262         Gets the current pen.
1263
1264         @see SetPen()
1265     */
1266     const wxPen& GetPen() const;
1267
1268     /**
1269         Sets the current background brush for the DC.
1270     */
1271     void SetBackground(const wxBrush& brush);
1272
1273     /**
1274         Sets the current brush for the DC.
1275
1276         If the argument is ::wxNullBrush (or another invalid brush; see wxBrush::IsOk),
1277         the current brush is selected out of the device context (leaving wxDC without
1278         any valid brush), allowing the current brush to be destroyed safely.
1279
1280         @see wxBrush, wxMemoryDC (for the interpretation of colours when
1281              drawing into a monochrome bitmap)
1282     */
1283     void SetBrush(const wxBrush& brush);
1284
1285     /**
1286         Sets the current pen for the DC.
1287
1288         If the argument is ::wxNullPen (or another invalid pen; see wxPen::IsOk),
1289         the current pen is selected out of the device context (leaving wxDC without any
1290         valid pen), allowing the current pen to be destroyed safely.
1291
1292         @see wxMemoryDC for the interpretation of colours when drawing into a
1293              monochrome bitmap.
1294     */
1295     void SetPen(const wxPen& pen);
1296
1297     //@}
1298
1299
1300     /**
1301         Copy attributes from another DC.
1302
1303         The copied attributes currently are:
1304             - Font
1305             - Text foreground and background colours
1306             - Background brush
1307             - Layout direction
1308
1309         @param dc
1310             A valid (i.e. its IsOk() must return @true) source device context.
1311      */
1312     void CopyAttributes(const wxDC& dc);
1313
1314     /**
1315         Returns the depth (number of bits/pixel) of this DC.
1316
1317         @see wxDisplayDepth()
1318     */
1319     int GetDepth() const;
1320
1321     /**
1322         Returns the current device origin.
1323
1324         @see SetDeviceOrigin()
1325     */
1326     wxPoint GetDeviceOrigin() const;
1327
1328     /**
1329         Gets the current logical function.
1330
1331         @see SetLogicalFunction()
1332     */
1333     wxRasterOperationMode GetLogicalFunction() const;
1334
1335     /**
1336         Gets the current mapping mode for the device context.
1337
1338         @see SetMapMode()
1339     */
1340     wxMappingMode GetMapMode() const;
1341
1342     /**
1343         Gets in @a colour the colour at the specified location. Not available
1344         for wxPostScriptDC or wxMetafileDC.
1345
1346         @note Setting a pixel can be done using DrawPoint().
1347
1348         @note This method shouldn't be used with wxPaintDC as accessing the DC
1349         while drawing can result in unexpected results, notably in wxGTK.
1350     */
1351     bool GetPixel(wxCoord x, wxCoord y, wxColour* colour) const;
1352
1353     /**
1354         Returns the resolution of the device in pixels per inch.
1355     */
1356     wxSize GetPPI() const;
1357
1358     /**
1359         Gets the horizontal and vertical extent of this device context in @e device units.
1360         It can be used to scale graphics to fit the page.
1361
1362         For example, if @e maxX and @e maxY represent the maximum horizontal
1363         and vertical 'pixel' values used in your application, the following
1364         code will scale the graphic to fit on the printer page:
1365
1366         @code
1367         wxCoord w, h;
1368         dc.GetSize(&w, &h);
1369         double scaleX = (double)(maxX / w);
1370         double scaleY = (double)(maxY / h);
1371         dc.SetUserScale(min(scaleX, scaleY),min(scaleX, scaleY));
1372         @endcode
1373
1374         @beginWxPerlOnly
1375         In wxPerl there are two methods instead of a single overloaded
1376         method:
1377         - GetSize(): returns a Wx::Size object.
1378         - GetSizeWH(): returns a 2-element list (width, height).
1379         @endWxPerlOnly
1380     */
1381     void GetSize(wxCoord* width, wxCoord* height) const;
1382
1383     /**
1384         @overload
1385     */
1386     wxSize GetSize() const;
1387
1388     /**
1389         Returns the horizontal and vertical resolution in millimetres.
1390     */
1391     void GetSizeMM(wxCoord* width, wxCoord* height) const;
1392
1393     /**
1394         @overload
1395     */
1396     wxSize GetSizeMM() const;
1397
1398     /**
1399         Gets the current user scale factor.
1400
1401         @beginWxPerlOnly
1402         In wxPerl this method takes no arguments and return a two
1403         element array (x, y).
1404         @endWxPerlOnly
1405
1406         @see SetUserScale()
1407     */
1408     void GetUserScale(double* x, double* y) const;
1409
1410     /**
1411         Returns @true if the DC is ok to use.
1412     */
1413     bool IsOk() const;
1414
1415     /**
1416         Sets the x and y axis orientation (i.e., the direction from lowest to
1417         highest values on the axis). The default orientation is x axis from
1418         left to right and y axis from top down.
1419
1420         @param xLeftRight
1421             True to set the x axis orientation to the natural left to right
1422             orientation, @false to invert it.
1423         @param yBottomUp
1424             True to set the y axis orientation to the natural bottom up
1425             orientation, @false to invert it.
1426     */
1427     void SetAxisOrientation(bool xLeftRight, bool yBottomUp);
1428
1429     /**
1430         Sets the device origin (i.e., the origin in pixels after scaling has
1431         been applied). This function may be useful in Windows printing
1432         operations for placing a graphic on a page.
1433     */
1434     void SetDeviceOrigin(wxCoord x, wxCoord y);
1435
1436     /**
1437         Sets the current logical function for the device context.
1438         It determines how a @e source pixel (from a pen or brush colour, or source
1439         device context if using Blit()) combines with a @e destination pixel in
1440         the current device context.
1441         Text drawing is not affected by this function.
1442
1443         See ::wxRasterOperationMode enumeration values for more info.
1444
1445         The default is @c wxCOPY, which simply draws with the current colour.
1446         The others combine the current colour and the background using a logical
1447         operation. @c wxINVERT is commonly used for drawing rubber bands or moving
1448         outlines, since drawing twice reverts to the original colour.
1449     */
1450     void SetLogicalFunction(wxRasterOperationMode function);
1451
1452     /**
1453         The mapping mode of the device context defines the unit of measurement
1454         used to convert @e logical units to @e device units.
1455
1456         Note that in X, text drawing isn't handled consistently with the mapping mode;
1457         a font is always specified in point size. However, setting the user scale (see
1458         SetUserScale()) scales the text appropriately. In Windows, scalable
1459         TrueType fonts are always used; in X, results depend on availability of
1460         fonts, but usually a reasonable match is found.
1461
1462         The coordinate origin is always at the top left of the screen/printer.
1463
1464         Drawing to a Windows printer device context uses the current mapping
1465         mode, but mapping mode is currently ignored for PostScript output.
1466     */
1467     void SetMapMode(wxMappingMode mode);
1468
1469     /**
1470         If this is a window DC or memory DC, assigns the given palette to the
1471         window or bitmap associated with the DC. If the argument is
1472         ::wxNullPalette, the current palette is selected out of the device
1473         context, and the original palette restored.
1474
1475         @see wxPalette
1476     */
1477     void SetPalette(const wxPalette& palette);
1478
1479     /**
1480         Sets the user scaling factor, useful for applications which require
1481         'zooming'.
1482     */
1483     void SetUserScale(double xScale, double yScale);
1484
1485
1486     /**
1487         @name Transformation matrix
1488
1489         See the notes about the availability of these functions in the class
1490         documentation.
1491     */
1492     //@{
1493
1494     /**
1495         Check if the use of transformation matrix is supported by the current
1496         system.
1497
1498         Currently this function always returns @false for non-MSW platforms and
1499         may return @false for old (Windows 9x/ME) Windows systems. Normally
1500         support for the transformation matrix is always available in any
1501         relatively recent Windows versions.
1502
1503         @since 2.9.2
1504     */
1505     bool CanUseTransformMatrix() const;
1506
1507     /**
1508         Set the transformation matrix.
1509
1510         If transformation matrix is supported on the current system, the
1511         specified @a matrix will be used to transform between wxDC and physical
1512         coordinates. Otherwise the function returns @false and doesn't change
1513         the coordinate mapping.
1514
1515         @since 2.9.2
1516     */
1517     bool SetTransformMatrix(const wxAffineMatrix2D& matrix);
1518
1519     /**
1520         Return the transformation matrix used by this device context.
1521
1522         By default the transformation matrix is the identity matrix.
1523
1524         @since 2.9.2
1525     */
1526     wxAffineMatrix2D GetTransformMatrix() const;
1527
1528     /**
1529         Revert the transformation matrix to identity matrix.
1530
1531         @since 2.9.2
1532     */
1533     void ResetTransformMatrix();
1534
1535     //@}
1536
1537
1538     /**
1539         @name query capabilities
1540     */
1541     //@{
1542
1543     /**
1544        Does the DC support drawing bitmaps?
1545     */
1546     bool CanDrawBitmap() const;
1547
1548     /**
1549        Does the DC supoprt calculating the size required to draw text?
1550     */
1551     bool CanGetTextExtent() const;
1552
1553     //@}
1554
1555     /**
1556        Returns a value that can be used as a handle to the native drawing
1557        context, if this wxDC has something that could be thought of in that
1558        way.  (Not all of them do.)
1559
1560        For example, on Windows the return value is an HDC, on OSX it is a
1561        CGContextRef and on wxGTK it will be a GdkDrawable.  If the DC is a
1562        wxGCDC then the return value will be the value returned from
1563        wxGraphicsContext::GetNativeContext.  A value of NULL is returned if
1564        the DC does not have anything that fits the handle concept.
1565
1566        @since 2.9.5
1567      */
1568     void* GetHandle() const;
1569
1570
1571     /**
1572        If supported by the platform and the type of DC, fetch the contents of the DC, or a subset of it, as a bitmap.
1573     */
1574     wxBitmap GetAsBitmap(const wxRect *subrect = NULL) const;
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 helper class for setting a clipping region on a wxDC
1591     during its lifetime.
1592
1593     An object of wxDCClipper class is typically created on the stack so that it
1594     is automatically destroyed when the object goes out of scope. A typical
1595     usage example:
1596
1597     @code
1598     void MyFunction(wxDC& dc)
1599     {
1600         wxDCClipper clip(dc, rect);
1601         // ... drawing functions here are affected by clipping rect ...
1602     }
1603
1604     void OtherFunction()
1605     {
1606         wxDC dc;
1607         MyFunction(dc);
1608         // ... drawing functions here are not affected by clipping rect ...
1609     }
1610     @endcode
1611
1612     @note Unlike other similar classes such as wxDCFontChanger, wxDCClipper
1613         currently doesn't restore the previously active clipping region when it
1614         is destroyed but simply resets clipping on the associated wxDC. This
1615         may be changed in the future wxWidgets versions but has to be taken
1616         into account explicitly in the current one.
1617
1618     @library{wxcore}
1619     @category{gdi}
1620
1621     @see wxDC::SetClippingRegion(), wxDCFontChanger, wxDCTextColourChanger, wxDCPenChanger,
1622          wxDCBrushChanger
1623 */
1624 class wxDCClipper
1625 {
1626 public:
1627     //@{
1628     /**
1629         Sets the clipping region to the specified region/coordinates.
1630
1631         The clipping region is automatically unset when this object is destroyed.
1632     */
1633     wxDCClipper(wxDC& dc, const wxRegion& region);
1634     wxDCClipper(wxDC& dc, const wxRect& rect);
1635     wxDCClipper(wxDC& dc, wxCoord x, wxCoord y, wxCoord w, wxCoord h);
1636     //@}
1637
1638     /**
1639         Destroys the clipping region associated with the DC passed to the ctor.
1640     */
1641     ~wxDCClipper();
1642 };
1643
1644
1645 /**
1646     @class wxDCBrushChanger
1647
1648     wxDCBrushChanger is a small helper class for setting a brush on a wxDC
1649     and unsetting it automatically in the destructor, restoring the previous one.
1650
1651     @library{wxcore}
1652     @category{gdi}
1653
1654     @see wxDC::SetBrush(), wxDCFontChanger, wxDCTextColourChanger, wxDCPenChanger,
1655          wxDCClipper
1656 */
1657 class wxDCBrushChanger
1658 {
1659 public:
1660     /**
1661         Sets @a brush on the given @a dc, storing the old one.
1662
1663         @param dc
1664             The DC where the brush must be temporary set.
1665         @param brush
1666             The brush to set.
1667     */
1668     wxDCBrushChanger(wxDC& dc, const wxBrush& brush);
1669
1670     /**
1671         Restores the brush originally selected in the DC passed to the ctor.
1672     */
1673     ~wxDCBrushChanger();
1674 };
1675
1676
1677 /**
1678     @class wxDCPenChanger
1679
1680     wxDCPenChanger is a small helper class for setting a pen on a wxDC
1681     and unsetting it automatically in the destructor, restoring the previous one.
1682
1683     @library{wxcore}
1684     @category{gdi}
1685
1686     @see wxDC::SetPen(), wxDCFontChanger, wxDCTextColourChanger, wxDCBrushChanger,
1687          wxDCClipper
1688 */
1689 class wxDCPenChanger
1690 {
1691 public:
1692     /**
1693         Sets @a pen on the given @a dc, storing the old one.
1694
1695         @param dc
1696             The DC where the pen must be temporary set.
1697         @param pen
1698             The pen to set.
1699     */
1700     wxDCPenChanger(wxDC& dc, const wxPen& pen);
1701
1702     /**
1703         Restores the pen originally selected in the DC passed to the ctor.
1704     */
1705     ~wxDCPenChanger();
1706 };
1707
1708
1709
1710 /**
1711     @class wxDCTextColourChanger
1712
1713     wxDCTextColourChanger is a small helper class for setting a foreground
1714     text colour on a wxDC and unsetting it automatically in the destructor,
1715     restoring the previous one.
1716
1717     @library{wxcore}
1718     @category{gdi}
1719
1720     @see wxDC::SetTextForeground(), wxDCFontChanger, wxDCPenChanger, wxDCBrushChanger,
1721          wxDCClipper
1722 */
1723 class wxDCTextColourChanger
1724 {
1725 public:
1726     /**
1727         Trivial constructor not changing anything.
1728
1729         This constructor is useful if you don't know beforehand if the colour
1730         needs to be changed or not. It simply creates the object which won't do
1731         anything in its destructor unless Set() is called -- in which case it
1732         would reset the previous colour.
1733      */
1734     wxDCTextColourChanger(wxDC& dc);
1735
1736     /**
1737         Sets @a col on the given @a dc, storing the old one.
1738
1739         @param dc
1740             The DC where the colour must be temporary set.
1741         @param col
1742             The colour to set.
1743     */
1744     wxDCTextColourChanger(wxDC& dc, const wxColour& col);
1745
1746     /**
1747         Set the colour to use.
1748
1749         This method is meant to be called once only and only on the objects
1750         created with the constructor overload not taking wxColour argument and
1751         has the same effect as the other constructor, i.e. sets the colour to
1752         the given @a col and ensures that the old value is restored when this
1753         object is destroyed.
1754      */
1755     void Set(const wxColour& col);
1756
1757     /**
1758         Restores the colour originally selected in the DC passed to the ctor.
1759     */
1760     ~wxDCTextColourChanger();
1761 };
1762
1763
1764
1765 /**
1766     @class wxDCFontChanger
1767
1768     wxDCFontChanger is a small helper class for setting a font on a wxDC and
1769     unsetting it automatically in the destructor, restoring the previous one.
1770
1771     @since 2.9.0
1772
1773     @library{wxcore}
1774     @category{gdi}
1775
1776     @see wxDC::SetFont(), wxDCTextColourChanger, wxDCPenChanger, wxDCBrushChanger,
1777          wxDCClipper
1778 */
1779 class wxDCFontChanger
1780 {
1781 public:
1782     /**
1783         Trivial constructor not changing anything.
1784
1785         This constructor is useful if you don't know beforehand if the font
1786         needs to be changed or not. It simply creates the object which won't do
1787         anything in its destructor unless Set() is called -- in which case it
1788         would reset the previous font.
1789
1790         @since 2.9.1
1791      */
1792     wxDCFontChanger(wxDC& dc);
1793
1794     /**
1795         Sets @a font on the given @a dc, storing the old one.
1796
1797         @param dc
1798             The DC where the font must be temporary set.
1799         @param font
1800             The font to set.
1801     */
1802     wxDCFontChanger(wxDC& dc, const wxFont& font);
1803
1804     /**
1805         Set the font to use.
1806
1807         This method is meant to be called once only and only on the objects
1808         created with the constructor overload not taking wxColour argument and
1809         has the same effect as the other constructor, i.e. sets the font to
1810         the given @a font and ensures that the old value is restored when this
1811         object is destroyed.
1812      */
1813     void Set(const wxFont& font);
1814
1815     /**
1816         Restores the font originally selected in the DC passed to the ctor.
1817     */
1818     ~wxDCFontChanger();
1819 };
1820