X-Git-Url: https://git.saurik.com/wxWidgets.git/blobdiff_plain/e39954934300b29f5e12f3142c1c6be25f659677..92c0fc34c104c8d7c12d6a3b78ea232690fc23f4:/interface/wx/dc.h?ds=sidebyside diff --git a/interface/wx/dc.h b/interface/wx/dc.h index 9184ee8900..41dfbdaba0 100644 --- a/interface/wx/dc.h +++ b/interface/wx/dc.h @@ -2,8 +2,7 @@ // Name: dc.h // Purpose: interface of wxDC // Author: wxWidgets team -// RCS-ID: $Id$ -// Licence: wxWindows license +// Licence: wxWindows licence ///////////////////////////////////////////////////////////////////////////// @@ -73,12 +72,34 @@ enum wxMappingMode wxMM_TWIPS, /** - Each logical unit is a @e "printer point" i.e. 1/72 of an inch. + Each logical unit is a @e "printer point" i.e.\ 1/72 of an inch. Equivalent to about 353 micrometers. */ wxMM_POINTS }; +/** + Simple collection of various font metrics. + + This object is returned by wxDC::GetFontMetrics(). + + @since 2.9.2 + + @library{wxcore} + @category{dc,gdi} + */ +struct wxFontMetrics +{ + /// Constructor initializes all fields to 0. + wxFontMetrics(); + + int height, ///< Total character height. + ascent, ///< Part of the height above the baseline. + descent, ///< Part of the height below the baseline. + internalLeading, ///< Intra-line spacing. + externalLeading, ///< Inter-line spacing. + averageWidth; ///< Average font width, a.k.a. "x-width". +}; /** @@ -91,7 +112,7 @@ enum wxMappingMode wxWidgets offers an alternative drawing API based on the modern drawing backends GDI+, CoreGraphics and Cairo. See wxGraphicsContext, wxGraphicsRenderer and related classes. There is also a wxGCDC linking the APIs by offering - the wxDC API ontop of a wxGraphicsContext. + the wxDC API on top of a wxGraphicsContext. wxDC is an abstract base class and cannot be created directly. Use wxPaintDC, wxClientDC, wxWindowDC, wxScreenDC, wxMemoryDC or @@ -121,7 +142,7 @@ enum wxMappingMode a device unit is a @e pixel. For a printer, the device unit is defined by the resolution of the printer (usually given in @c DPI: dot-per-inch). - All wxDC functions use instead @b logical units, unless where explicitely + All wxDC functions use instead @b logical units, unless where explicitly stated. Logical units are arbitrary units mapped to device units using the current mapping mode (see wxDC::SetMapMode). @@ -131,9 +152,25 @@ enum wxMappingMode @section dc_alpha_support Support for Transparency / Alpha Channel - On Mac OS X colours with alpha channel are supported. Instances of wxPen - or wxBrush that are built from wxColour use the colour's alpha values - when stroking or filling. + In general wxDC methods don't support alpha transparency and the alpha + component of wxColour is simply ignored and you need to use wxGraphicsContext + for full transparency support. There are, however, a few exceptions: first, + under Mac OS X colours with alpha channel are supported in all the normal + wxDC-derived classes as they use wxGraphicsContext internally. Second, + under all platforms wxSVGFileDC also fully supports alpha channel. In both + of these cases the instances of wxPen or wxBrush that are built from + wxColour use the colour's alpha values when stroking or filling. + + + @section Support for Transformation Matrix + + On some platforms (currently only under MSW and only on Windows NT, i.e. + not Windows 9x/ME, systems) wxDC has support for applying an arbitrary + affine transformation matrix to its coordinate system. Call + CanUseTransformMatrix() to check if this support is available and then call + SetTransformMatrix() if it is. If the transformation matrix is not + supported, SetTransformMatrix() always simply returns false and doesn't do + anything. @library{wxcore} @@ -222,15 +259,21 @@ public: /** Draws an arc of a circle, centred on (@a xc, @a yc), with starting - point (@a x1, @a y1) and ending at (@a x2, @a y2). The current pen is - used for the outline and the current brush for filling the shape. + point (@a xStart, @a yStart) and ending at (@a xEnd, @a yEnd). + The current pen is used for the outline and the current brush for + filling the shape. The arc is drawn in a counter-clockwise direction from the start point to the end point. */ - void DrawArc(wxCoord x1, wxCoord y1, wxCoord x2, wxCoord y2, + void DrawArc(wxCoord xStart, wxCoord yStart, wxCoord xEnd, wxCoord yEnd, wxCoord xc, wxCoord yc); + /** + @overload + */ + void DrawArc(const wxPoint& ptStart, const wxPoint& ptEnd, const wxPoint& centre); + /** Draw a bitmap on the device context at the specified point. If @a transparent is @true and the bitmap has a transparency mask, the @@ -246,6 +289,12 @@ public: void DrawBitmap(const wxBitmap& bitmap, wxCoord x, wxCoord y, bool useMask = false); + /** + @overload + */ + void DrawBitmap(const wxBitmap &bmp, const wxPoint& pt, + bool useMask = false); + /** Draws a check mark inside the given rectangle. */ @@ -306,6 +355,12 @@ public: void DrawEllipticArc(wxCoord x, wxCoord y, wxCoord width, wxCoord height, double start, double end); + /** + @overload + */ + void DrawEllipticArc(const wxPoint& pt, const wxSize& sz, + double sa, double ea); + /** Draw an icon on the display (does nothing if the device context is PostScript). This can be the simplest way of drawing bitmaps on a @@ -313,13 +368,18 @@ public: */ void DrawIcon(const wxIcon& icon, wxCoord x, wxCoord y); + /** + @overload + */ + void DrawIcon(const wxIcon& icon, const wxPoint& pt); + /** Draw optional bitmap and the text into the given rectangle and aligns it as specified by alignment parameter; it also will emphasize the character with the given index if it is != -1 and return the bounding rectangle if required. */ - void DrawLabel(const wxString& text, const wxBitmap& image, + void DrawLabel(const wxString& text, const wxBitmap& bitmap, const wxRect& rect, int alignment = wxALIGN_LEFT | wxALIGN_TOP, int indexAccel = -1, wxRect* rectBounding = NULL); @@ -339,26 +399,31 @@ public: */ void DrawLine(wxCoord x1, wxCoord y1, wxCoord x2, wxCoord y2); + /** + @overload + */ + void DrawLine(const wxPoint& pt1, const wxPoint& pt2); + /** Draws lines using an array of points of size @a n adding the optional offset coordinate. The current pen is used for drawing the lines. - @beginWxPythonOnly - The wxPython version of this method accepts a Python list of wxPoint - objects. - @endWxPythonOnly + @beginWxPerlOnly + Not supported by wxPerl. + @endWxPerlOnly */ - void DrawLines(int n, wxPoint points[], wxCoord xoffset = 0, + void DrawLines(int n, const wxPoint points[], wxCoord xoffset = 0, wxCoord yoffset = 0); /** This method uses a list of wxPoints, adding the optional offset coordinate. The programmer is responsible for deleting the list of points. - @beginWxPythonOnly - The wxPython version of this method accepts a Python list of wxPoint - objects. - @endWxPythonOnly + @beginWxPerlOnly + The wxPerl version of this method accepts + as its first parameter a reference to an array + of wxPoint objects. + @endWxPerlOnly */ void DrawLines(const wxPointList* points, wxCoord xoffset = 0, wxCoord yoffset = 0); @@ -369,6 +434,11 @@ public: */ void DrawPoint(wxCoord x, wxCoord y); + /** + @overload + */ + void DrawPoint(const wxPoint& pt); + /** Draws a filled polygon using an array of points of size @a n, adding the optional offset coordinate. The first and last points are @@ -379,8 +449,12 @@ public: The current pen is used for drawing the outline, and the current brush for filling the shape. Using a transparent brush suppresses filling. + + @beginWxPerlOnly + Not supported by wxPerl. + @endWxPerlOnly */ - void DrawPolygon(int n, wxPoint points[], wxCoord xoffset = 0, + void DrawPolygon(int n, const wxPoint points[], wxCoord xoffset = 0, wxCoord yoffset = 0, wxPolygonFillMode fill_style = wxODDEVEN_RULE); /** @@ -396,10 +470,11 @@ public: The programmer is responsible for deleting the list of points. - @beginWxPythonOnly - The wxPython version of this method accepts a Python list of wxPoint - objects. - @endWxPythonOnly + @beginWxPerlOnly + The wxPerl version of this method accepts + as its first parameter a reference to an array + of wxPoint objects. + @endWxPerlOnly */ void DrawPolygon(const wxPointList* points, wxCoord xoffset = 0, wxCoord yoffset = 0, @@ -427,12 +502,8 @@ public: call to DrawPolyPolygon() must be closed. Unlike polygons created by the DrawPolygon() member function, the polygons created by this method are not closed automatically. - - @beginWxPythonOnly - Not implemented yet. - @endWxPythonOnly */ - void DrawPolyPolygon(int n, int count[], wxPoint points[], + void DrawPolyPolygon(int n, const int count[], const wxPoint points[], wxCoord xoffset = 0, wxCoord yoffset = 0, wxPolygonFillMode fill_style = wxODDEVEN_RULE); @@ -444,7 +515,18 @@ public: void DrawRectangle(wxCoord x, wxCoord y, wxCoord width, wxCoord height); /** - Draws the text rotated by @a angle degrees. + @overload + */ + void DrawRectangle(const wxPoint& pt, const wxSize& sz); + + /** + @overload + */ + void DrawRectangle(const wxRect& rect); + + /** + Draws the text rotated by @a angle degrees + (positive angles are counterclockwise; the full angle is 360 degrees). @note Under Win9x only TrueType fonts can be drawn by this function. In particular, a font different from @c wxNORMAL_FONT should be used @@ -456,6 +538,12 @@ public: void DrawRotatedText(const wxString& text, wxCoord x, wxCoord y, double angle); + /** + @overload + */ + void DrawRotatedText(const wxString& text, const wxPoint& point, + double angle); + /** Draws a rectangle with the given top left corner, and with the given size. The corners are quarter-circles using the given radius. The @@ -472,23 +560,45 @@ public: void DrawRoundedRectangle(wxCoord x, wxCoord y, wxCoord width, wxCoord height, double radius); + /** + @overload + */ + void DrawRoundedRectangle(const wxPoint& pt, const wxSize& sz, + double radius); + + /** + @overload + */ + void DrawRoundedRectangle(const wxRect& rect, double radius); + /** Draws a spline between all given points using the current pen. - @beginWxPythonOnly - The wxPython version of this method accepts a Python list of wxPoint - objects. - @endWxPythonOnly + @beginWxPerlOnly + Not supported by wxPerl. + @endWxPerlOnly */ - void DrawSpline(int n, wxPoint points[]); + void DrawSpline(int n, const wxPoint points[]); /** @overload + + + @beginWxPerlOnly + The wxPerl version of this method accepts + as its first parameter a reference to an array + of wxPoint objects. + @endWxPerlOnly */ void DrawSpline(const wxPointList* points); /** @overload + + + @beginWxPerlOnly + Not supported by wxPerl. + @endWxPerlOnly */ void DrawSpline(wxCoord x1, wxCoord y1, wxCoord x2, wxCoord y2, wxCoord x3, wxCoord y3); @@ -499,13 +609,23 @@ public: The coordinates refer to the top-left corner of the rectangle bounding the string. See GetTextExtent() for how to get the dimensions of a text - string, which can be used to position the text more precisely. + string, which can be used to position the text more precisely and + DrawLabel() if you need to align the string differently. + + Starting from wxWidgets 2.9.2 @a text parameter can be a multi-line + string, i.e. contain new line characters, and will be rendered + correctly. @note The current @ref GetLogicalFunction() "logical function" is ignored by this function. */ void DrawText(const wxString& text, wxCoord x, wxCoord y); + /** + @overload + */ + void DrawText(const wxString& text, const wxPoint& pt); + /** Fill the area specified by rect with a radial gradient, starting from @a initialColour at the centre of the circle and fading to @@ -557,15 +677,31 @@ public: - wxFLOOD_BORDER: The area to be flooded is bounded by the given colour. + Currently this method is not implemented in wxOSX and does nothing + there. + @return @false if the operation failed. @note The present implementation for non-Windows platforms may fail to find colour borders if the pixels do not match the colour exactly. However the function will still return @true. + + @note This method shouldn't be used with wxPaintDC under non-Windows + platforms as it uses GetPixel() internally and this may give + wrong results, notably in wxGTK. If you need to flood fill + wxPaintDC, create a temporary wxMemoryDC, flood fill it and then + blit it to, or draw as a bitmap on, wxPaintDC. See the example of + doing this in the drawing sample and wxBufferedPaintDC class. */ bool FloodFill(wxCoord x, wxCoord y, const wxColour& colour, wxFloodFillStyle style = wxFLOOD_SURFACE); + /** + @overload + */ + bool FloodFill(const wxPoint& pt, const wxColour& col, + wxFloodFillStyle style = wxFLOOD_SURFACE); + /** Displays a cross hair using the current pen. This is a vertical and horizontal line the height and width of the window, centred on the @@ -573,6 +709,11 @@ public: */ void CrossHair(wxCoord x, wxCoord y); + /** + @overload + */ + void CrossHair(const wxPoint& pt); + //@} @@ -590,24 +731,26 @@ public: /** Gets the rectangle surrounding the current clipping region. - - @beginWxPythonOnly - No arguments are required and the four values defining the rectangle - are returned as a tuple. - @endWxPythonOnly */ void GetClippingBox(wxCoord *x, wxCoord *y, wxCoord *width, wxCoord *height) const; /** Sets the clipping region for this device context to the intersection of the given region described by the parameters of this method and the - previously set clipping region. You should call DestroyClippingRegion() - if you want to set the clipping region exactly to the region specified. + previously set clipping region. The clipping region is an area to which drawing is restricted. Possible uses for the clipping region are for clipping text or for speeding up window redraws when only a known area of the screen is damaged. + Notice that you need to call DestroyClippingRegion() if you want to set + the clipping region exactly to the region specified. + + Also note that if the clipping region is empty, any previously set + clipping region is destroyed, i.e. it is equivalent to calling + DestroyClippingRegion(), and not to clipping out all drawing on the DC + as might be expected. + @see DestroyClippingRegion(), wxRegion */ void SetClippingRegion(wxCoord x, wxCoord y, wxCoord width, wxCoord height); @@ -648,6 +791,21 @@ public: */ wxCoord GetCharWidth() const; + /** + Returns the various font characteristics. + + This method allows to retrieve some of the font characteristics not + returned by GetTextExtent(), notably internal leading and average + character width. + + Currently this method returns correct results only under wxMSW, in the + other ports the internal leading will always be 0 and the average + character width will be computed as the width of the character 'x'. + + @since 2.9.2 + */ + wxFontMetrics GetFontMetrics() const; + /** Gets the dimensions of the string using the currently selected font. @a string is the text string to measure, @e heightLine, if non @NULL, @@ -661,6 +819,12 @@ public: @note This function works with both single-line and multi-line strings. + @beginWxPerlOnly + In wxPerl this method is implemented as + GetMultiLineTextExtent(string, font = undef) returning a + 3-element list (width, height, line_height) + @endWxPerlOnly + @see wxFont, SetFont(), GetPartialTextExtents(), GetTextExtent() */ void GetMultiLineTextExtent(const wxString& string, wxCoord* w, @@ -676,6 +840,10 @@ public: @note This function works with both single-line and multi-line strings. + @beginWxPerlOnly + Not supported by wxPerl. + @endWxPerlOnly + @see wxFont, SetFont(), GetPartialTextExtents(), GetTextExtent() */ wxSize GetMultiLineTextExtent(const wxString& string) const; @@ -688,10 +856,10 @@ public: function that is faster or more accurate than the generic implementation then it should be used instead. - @beginWxPythonOnly - This method only takes the @a text parameter and returns a Python list - of integers. - @endWxPythonOnly + @beginWxPerlOnly + In wxPerl this method only takes the @a text parameter and + returns the widths as a list of integers. + @endWxPerlOnly @see GetMultiLineTextExtent(), GetTextExtent() */ @@ -714,12 +882,11 @@ public: @note This function only works with single-line strings. - @beginWxPythonOnly - The following methods are implemented in wxPython: - - GetTextExtent(string) - Returns a 2-tuple, (width, height). - - GetFullTextExtent(string, font=NULL) - - Returns a 4-tuple, (width, height, descent, externalLeading). - @endWxPythonOnly + @beginWxPerlOnly + In wxPerl this method is implemented as GetTextExtent(string, + font = undef) returning a 4-element list (width, height, + descent, externalLeading) + @endWxPerlOnly @see wxFont, SetFont(), GetPartialTextExtents(), GetMultiLineTextExtent() @@ -731,6 +898,11 @@ public: /** @overload + + + @beginWxPerlOnly + Not supported by wxPerl. + @endWxPerlOnly */ wxSize GetTextExtent(const wxString& string) const; @@ -750,10 +922,11 @@ public: int GetBackgroundMode() const; /** - Gets the current font. Notice that even although each device context - object has some default font after creation, this method would return a - ::wxNullFont initially and only after calling SetFont() a valid font is - returned. + Gets the current font. + + Notice that even although each device context object has some default font + after creation, this method would return a ::wxNullFont initially and only + after calling SetFont() a valid font is returned. */ const wxFont& GetFont() const; @@ -782,14 +955,19 @@ public: const wxColour& GetTextForeground() const; /** - @a mode may be one of wxSOLID and wxTRANSPARENT. This setting - determines whether text will be drawn with a background colour or not. + @a mode may be one of @c wxSOLID and @c wxTRANSPARENT. + + This setting determines whether text will be drawn with a background + colour or not. */ void SetBackgroundMode(int mode); /** - Sets the current font for the DC. It must be a valid font, in - particular you should not pass wxNullFont to this method. + Sets the current font for the DC. + + If the argument is ::wxNullFont (or another invalid font; see wxFont::IsOk), + the current font is selected out of the device context (leaving wxDC without + any valid font), allowing the current font to be destroyed safely. @see wxFont */ @@ -809,9 +987,11 @@ public: void SetTextForeground(const wxColour& colour); /** - Sets the current layout direction for the device context. @a dir may be - either @c wxLayout_Default, @c wxLayout_LeftToRight or - @c wxLayout_RightToLeft. + Sets the current layout direction for the device context. + + @param dir + May be either @c wxLayout_Default, @c wxLayout_LeftToRight or + @c wxLayout_RightToLeft. @see GetLayoutDirection() */ @@ -899,10 +1079,17 @@ public: //@{ /** - Copy from a source DC to this DC, specifying the destination - coordinates, size of area to copy, source DC, source coordinates, - logical function, whether to use a bitmap mask, and mask source - position. + Copy from a source DC to this DC. + + With this method you can specify the destination coordinates and the + size of area to copy which will be the same for both the source and + target DCs. If you need to apply scaling while copying, use + StretchBlit(). + + Notice that source DC coordinates @a xsrc and @a ysrc are interpreted + using the current source DC coordinate system, i.e. the scale, origin + position and axis directions are taken into account when transforming + them to physical (pixel) coordinates. @param xdest Destination device context x position. @@ -943,7 +1130,7 @@ public: This sequence of operations ensures that the source's transparent area need not be black, and logical functions are supported. @n @b Note: on Windows, blitting with masks can be speeded up - considerably by compiling wxWidgets with the wxUSE_DC_CACHE option + considerably by compiling wxWidgets with the wxUSE_DC_CACHEING option enabled. You can also influence whether MaskBlt or the explicit mask blitting code above is used, by using wxSystemOptions and setting the @c no-maskblt option to 1. @@ -966,10 +1153,18 @@ public: wxCoord xsrcMask = wxDefaultCoord, wxCoord ysrcMask = wxDefaultCoord); /** - Copy from a source DC to this DC, specifying the destination - coordinates, destination size, source DC, source coordinates, size of - source area to copy, logical function, whether to use a bitmap mask, - and mask source position. + Copy from a source DC to this DC possibly changing the scale. + + Unlike Blit(), this method allows to specify different source and + destination region sizes, meaning that it can stretch or shrink it + while copying. The same can be achieved by changing the scale of the + source or target DC but calling this method is simpler and can also be + more efficient if the platform provides a native implementation of it. + + The meaning of its other parameters is the same as with Blit(), in + particular all source coordinates are interpreted using the source DC + coordinate system, i.e. are affected by its scale, origin translation + and axis direction. @param xdest Destination device context x position. @@ -1014,7 +1209,7 @@ public: This sequence of operations ensures that the source's transparent area need not be black, and logical functions are supported. @n @b Note: on Windows, blitting with masks can be speeded up - considerably by compiling wxWidgets with the wxUSE_DC_CACHE option + considerably by compiling wxWidgets with the wxUSE_DC_CACHEING option enabled. You can also influence whether MaskBlt or the explicit mask blitting code above is used, by using wxSystemOptions and setting the @c no-maskblt option to 1. @@ -1029,8 +1224,6 @@ public: There is partial support for Blit() in wxPostScriptDC, under X. - StretchBlit() is only implemented under wxMAC and wxMSW. - See wxMemoryDC for typical usage. @since 2.9.0 @@ -1082,9 +1275,9 @@ public: /** Sets the current brush for the DC. - If the argument is wxNullBrush, the current brush is selected out of - the device context (leaving wxDC without any valid brush), allowing the - current brush to be destroyed safely. + If the argument is ::wxNullBrush (or another invalid brush; see wxBrush::IsOk), + the current brush is selected out of the device context (leaving wxDC without + any valid brush), allowing the current brush to be destroyed safely. @see wxBrush, wxMemoryDC (for the interpretation of colours when drawing into a monochrome bitmap) @@ -1092,9 +1285,11 @@ public: void SetBrush(const wxBrush& brush); /** - Sets the current pen for the DC. If the argument is wxNullPen, the - current pen is selected out of the device context (leaving wxDC without - any valid pen), allowing the current brush to be destroyed safely. + Sets the current pen for the DC. + + If the argument is ::wxNullPen (or another invalid pen; see wxPen::IsOk), + the current pen is selected out of the device context (leaving wxDC without any + valid pen), allowing the current pen to be destroyed safely. @see wxMemoryDC for the interpretation of colours when drawing into a monochrome bitmap. @@ -1104,6 +1299,19 @@ public: //@} + /** + Copy attributes from another DC. + + The copied attributes currently are: + - Font + - Text foreground and background colours + - Background brush + - Layout direction + + @param dc + A valid (i.e. its IsOk() must return @true) source device context. + */ + void CopyAttributes(const wxDC& dc); /** Returns the depth (number of bits/pixel) of this DC. @@ -1139,9 +1347,8 @@ public: @note Setting a pixel can be done using DrawPoint(). - @beginWxPythonOnly - The wxColour value is returned and is not required as a parameter. - @endWxPythonOnly + @note This method shouldn't be used with wxPaintDC as accessing the DC + while drawing can result in unexpected results, notably in wxGTK. */ bool GetPixel(wxCoord x, wxCoord y, wxColour* colour) const; @@ -1166,12 +1373,12 @@ public: dc.SetUserScale(min(scaleX, scaleY),min(scaleX, scaleY)); @endcode - @beginWxPythonOnly - In place of a single overloaded method name, wxPython implements the - following methods: - - GetSize() - Returns a wxSize. - - GetSizeWH() - Returns a 2-tuple (width, height). - @endWxPythonOnly + @beginWxPerlOnly + In wxPerl there are two methods instead of a single overloaded + method: + - GetSize(): returns a Wx::Size object. + - GetSizeWH(): returns a 2-element list (width, height). + @endWxPerlOnly */ void GetSize(wxCoord* width, wxCoord* height) const; @@ -1193,6 +1400,11 @@ public: /** Gets the current user scale factor. + @beginWxPerlOnly + In wxPerl this method takes no arguments and return a two + element array (x, y). + @endWxPerlOnly + @see SetUserScale() */ void GetUserScale(double* x, double* y) const; @@ -1203,7 +1415,7 @@ public: bool IsOk() const; /** - Sets the x and y axis orientation (i.e., the direction from lowest to + Sets the x and y axis orientation (i.e.\ the direction from lowest to highest values on the axis). The default orientation is x axis from left to right and y axis from top down. @@ -1217,7 +1429,7 @@ public: void SetAxisOrientation(bool xLeftRight, bool yBottomUp); /** - Sets the device origin (i.e., the origin in pixels after scaling has + Sets the device origin (i.e.\ the origin in pixels after scaling has been applied). This function may be useful in Windows printing operations for placing a graphic on a page. */ @@ -1271,6 +1483,105 @@ public: 'zooming'. */ void SetUserScale(double xScale, double yScale); + + + /** + @name Transformation matrix + + See the notes about the availability of these functions in the class + documentation. + */ + //@{ + + /** + Check if the use of transformation matrix is supported by the current + system. + + Currently this function always returns @false for non-MSW platforms and + may return @false for old (Windows 9x/ME) Windows systems. Normally + support for the transformation matrix is always available in any + relatively recent Windows versions. + + @since 2.9.2 + */ + bool CanUseTransformMatrix() const; + + /** + Set the transformation matrix. + + If transformation matrix is supported on the current system, the + specified @a matrix will be used to transform between wxDC and physical + coordinates. Otherwise the function returns @false and doesn't change + the coordinate mapping. + + @since 2.9.2 + */ + bool SetTransformMatrix(const wxAffineMatrix2D& matrix); + + /** + Return the transformation matrix used by this device context. + + By default the transformation matrix is the identity matrix. + + @since 2.9.2 + */ + wxAffineMatrix2D GetTransformMatrix() const; + + /** + Revert the transformation matrix to identity matrix. + + @since 2.9.2 + */ + void ResetTransformMatrix(); + + //@} + + + /** + @name query capabilities + */ + //@{ + + /** + Does the DC support drawing bitmaps? + */ + bool CanDrawBitmap() const; + + /** + Does the DC supoprt calculating the size required to draw text? + */ + bool CanGetTextExtent() const; + + //@} + + /** + Returns a value that can be used as a handle to the native drawing + context, if this wxDC has something that could be thought of in that + way. (Not all of them do.) + + For example, on Windows the return value is an HDC, on OSX it is a + CGContextRef and on wxGTK it will be a GdkDrawable. If the DC is a + wxGCDC then the return value will be the value returned from + wxGraphicsContext::GetNativeContext. A value of NULL is returned if + the DC does not have anything that fits the handle concept. + + @since 2.9.5 + */ + void* GetHandle() const; + + + /** + If supported by the platform and the type of DC, fetch the contents of the DC, or a subset of it, as a bitmap. + */ + wxBitmap GetAsBitmap(const wxRect *subrect = NULL) const; + + + void SetLogicalScale(double x, double y); + void GetLogicalScale(double *x, double *y) const; + void SetLogicalOrigin(wxCoord x, wxCoord y); + void GetLogicalOrigin(wxCoord *x, wxCoord *y) const; + wxPoint GetLogicalOrigin() const; + }; @@ -1278,10 +1589,12 @@ public: /** @class wxDCClipper - wxDCClipper is a small helper class for setting a clipping region on a wxDC - and unsetting it automatically. An object of wxDCClipper class is typically - created on the stack so that it is automatically destroyed when the object - goes out of scope. A typical usage example: + wxDCClipper is a helper class for setting a clipping region on a wxDC + during its lifetime. + + An object of wxDCClipper class is typically created on the stack so that it + is automatically destroyed when the object goes out of scope. A typical + usage example: @code void MyFunction(wxDC& dc) @@ -1298,6 +1611,12 @@ public: } @endcode + @note Unlike other similar classes such as wxDCFontChanger, wxDCClipper + currently doesn't restore the previously active clipping region when it + is destroyed but simply resets clipping on the associated wxDC. This + may be changed in the future wxWidgets versions but has to be taken + into account explicitly in the current one. + @library{wxcore} @category{gdi} @@ -1313,7 +1632,7 @@ public: The clipping region is automatically unset when this object is destroyed. */ - wxDCClipper(wxDC& dc, const wxRegion& r); + wxDCClipper(wxDC& dc, const wxRegion& region); wxDCClipper(wxDC& dc, const wxRect& rect); wxDCClipper(wxDC& dc, wxCoord x, wxCoord y, wxCoord w, wxCoord h); //@} @@ -1406,6 +1725,16 @@ public: class wxDCTextColourChanger { public: + /** + Trivial constructor not changing anything. + + This constructor is useful if you don't know beforehand if the colour + needs to be changed or not. It simply creates the object which won't do + anything in its destructor unless Set() is called -- in which case it + would reset the previous colour. + */ + wxDCTextColourChanger(wxDC& dc); + /** Sets @a col on the given @a dc, storing the old one. @@ -1416,6 +1745,17 @@ public: */ wxDCTextColourChanger(wxDC& dc, const wxColour& col); + /** + Set the colour to use. + + This method is meant to be called once only and only on the objects + created with the constructor overload not taking wxColour argument and + has the same effect as the other constructor, i.e. sets the colour to + the given @a col and ensures that the old value is restored when this + object is destroyed. + */ + void Set(const wxColour& col); + /** Restores the colour originally selected in the DC passed to the ctor. */ @@ -1441,6 +1781,18 @@ public: class wxDCFontChanger { public: + /** + Trivial constructor not changing anything. + + This constructor is useful if you don't know beforehand if the font + needs to be changed or not. It simply creates the object which won't do + anything in its destructor unless Set() is called -- in which case it + would reset the previous font. + + @since 2.9.1 + */ + wxDCFontChanger(wxDC& dc); + /** Sets @a font on the given @a dc, storing the old one. @@ -1452,7 +1804,18 @@ public: wxDCFontChanger(wxDC& dc, const wxFont& font); /** - Restores the colour originally selected in the DC passed to the ctor. + Set the font to use. + + This method is meant to be called once only and only on the objects + created with the constructor overload not taking wxColour argument and + has the same effect as the other constructor, i.e. sets the font to + the given @a font and ensures that the old value is restored when this + object is destroyed. + */ + void Set(const wxFont& font); + + /** + Restores the font originally selected in the DC passed to the ctor. */ ~wxDCFontChanger(); };