In this way, the same piece of code may write to a number of different devices,
if the device context is used as a parameter.
-Derived types of wxDC have documentation for specific features
-only, so refer to this section for most device context information.
+Notice that wxDC is an abstract base class and can't be created directly,
+please use \helpref{wxPaintDC}{wxpaintdc}, \helpref{wxClientDC}{wxclientdc},
+\helpref{wxWindowDC}{wxwindowdc}, \helpref{wxScreenDC}{wxscreendc},
+\helpref{wxMemoryDC}{wxmemorydc} or \helpref{wxPrinterDC}{wxprinterdc}.
% VZ: we should really document them instead of this lame excuse, but I don't
% have time for it now, when it is done please remove this
two {\tt wxCoord} ones or {\tt wxPoint} and {\tt wxSize} instead of four of
them.
+\wxheading{Support for Transparency / Alpha Channel}
+
+On Mac OS X when using Core Graphics (wx\_MAC\_USE\_CORE\_GRAPHICS set to 1)
+colors with alpha are supported, so instances {\tt wxPen} or {\tt wxBrush} that are built from {\tt wxColour} use
+the color's alpha values when stroking or filling.
+
\wxheading{Derived from}
\helpref{wxObject}{wxobject}
\latexignore{\rtfignore{\wxheading{Members}}}
-\membersection{wxDC::wxDC}
-
-\func{}{wxDC}{\void}
-
-Constructor.
-
-
-\membersection{wxDC::\destruct{wxDC}}
-
-\func{}{\destruct{wxDC}}{\void}
-
-Destructor.
-
-
-\membersection{wxDC::BeginDrawing}\label{wxdcbegindrawing}
-
-\func{void}{BeginDrawing}{\void}
-
-Allows optimization of drawing code under MS Windows. Enclose
-drawing primitives between {\bf BeginDrawing} and {\bf EndDrawing}\rtfsp
-calls.
-
-Drawing to a wxDialog panel device context outside of a
-system-generated OnPaint event {\it requires} this pair of calls to
-enclose drawing code. This is because a Windows dialog box does not have
-a retained device context associated with it, and selections such as pen
-and brush settings would be lost if the device context were obtained and
-released for each drawing operation.
-
-
\membersection{wxDC::Blit}\label{wxdcblit}
\func{bool}{Blit}{\param{wxCoord}{ xdest}, \param{wxCoord}{ ydest}, \param{wxCoord}{ width}, \param{wxCoord}{ height},
and logical functions are supported.
{\bf Note:} on Windows, blitting with masks can be speeded up considerably by compiling
-wxWindows with the wxUSE\_DC\_CACHE option enabled. You can also influence whether MaskBlt
+wxWidgets with the wxUSE\_DC\_CACHE option enabled. You can also influence whether MaskBlt
or the explicit mask blitting code above is used, by using \helpref{wxSystemOptions}{wxsystemoptions} and
setting the {\bf no-maskblt} option to 1.
\end{comment}
+\membersection{wxDC::ComputeScaleAndOrigin}\label{wxdccomputescaleandorigin}
+
+\func{virtual void}{ComputeScaleAndOrigin}{\void}
+
+Performs all necessary computations for given platform and context type
+after each change of scale and origin parameters. Usually called automatically
+internally after such changes.
+
+
\membersection{wxDC::CrossHair}\label{wxdccrosshair}
\func{void}{CrossHair}{\param{wxCoord}{ x}, \param{wxCoord}{ y}}
This can be the simplest way of drawing bitmaps on a window.
+\membersection{wxDC::DrawLabel}\label{wxdcdrawlabel}
+
+\func{virtual void}{DrawLabel}{\param{const wxString\&}{ text},
+ \param{const wxBitmap\&}{ image},
+ \param{const wxRect\&}{ rect},
+ \param{int}{ alignment = wxALIGN\_LEFT | wxALIGN\_TOP},
+ \param{int}{ indexAccel = -1},
+ \param{wxRect *}{rectBounding = NULL}}
+
+\func{void}{DrawLabel}{\param{const wxString\&}{ text}, \param{const wxRect\&}{ rect},
+ \param{int}{ alignment = wxALIGN\_LEFT | wxALIGN\_TOP},
+ \param{int}{ indexAccel = -1}}
+
+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.
+
+
\membersection{wxDC::DrawLine}\label{wxdcdrawline}
\func{void}{DrawLine}{\param{wxCoord}{ x1}, \param{wxCoord}{ y1}, \param{wxCoord}{ x2}, \param{wxCoord}{ y2}}
for filling the shape. Using a transparent brush suppresses filling.
The programmer is responsible for deleting the list of points.
-Note that wxWindows automatically closes the first and last points.
+Note that wxWidgets automatically closes the first and last points.
\pythonnote{The wxPython version of this method accepts a Python list
of wxPoint objects.}
\membersection{wxDC::DrawPolyPolygon}\label{wxdcdrawpolypolygon}
-\func{void}{DrawPolyPolygon}{\param{int }{n}, \param{int }{start[]}, \param{wxPoint }{points[]}, \param{wxCoord }{xoffset}, \param{wxCoord }{yoffset}, \param{int }{fillStyle = \texttt{wxODDEVEN\_RULE}}}
+\func{void}{DrawPolyPolygon}{\param{int}{ n}, \param{int}{ count[]}, \param{wxPoint}{ points[]}, \param{wxCoord}{ xoffset = 0}, \param{wxCoord}{ yoffset = 0},\\
+ \param{int }{fill\_style = wxODDEVEN\_RULE}}
+
+Draws two or more filled polygons using an array of {\it points}, adding the
+optional offset coordinates.
+
+Notice that for the platforms providing a native implementation
+of this function (Windows and PostScript-based wxDC currently), this is more
+efficient than using \helpref{DrawPolygon}{wxdcdrawpolygon} in a loop.
+
+{\it n} specifies the number of polygons to draw, the array {\it count} of size
+{\it n} specifies the number of points in each of the polygons in the
+{\it points} array.
+
+The last argument specifies the fill rule: {\bf wxODDEVEN\_RULE} (the default)
+or {\bf wxWINDING\_RULE}.
-Draw many polygons at once. For the platforms providing a native implementation
-of this function (Windows and PostScript-based wxDC), this is more efficient
-than using \helpref{DrawPolygon}{wxdcdrawpolygon} in a loop.
+The current pen is used for drawing the outline, and the current brush for
+filling the shape. Using a transparent brush suppresses filling.
+
+The polygons maybe disjoint or overlapping. Each polygon specified in a call to
+{\bf DrawPolyPolygon} must be closed. Unlike polygons created by the
+\helpref{DrawPolygon}{wxdcdrawpolygon} member function, the polygons created by
+{\bf DrawPolyPolygon} are not closed automatically.
+
+\pythonnote{Not implemented yet}
+
+\perlnote{Not implemented yet}
\membersection{wxDC::DrawPoint}\label{wxdcdrawpoint}
\func{void}{DrawPoint}{\param{wxCoord}{ x}, \param{wxCoord}{ y}}
-Draws a point using the current pen.
+Draws a point using the color of the current pen. Note that the other properties of the pen are not used, such as width etc..
\membersection{wxDC::DrawRectangle}\label{wxdcdrawrectangle}
\membersection{wxDC::DrawRoundedRectangle}\label{wxdcdrawroundedrectangle}
-\func{void}{DrawRoundedRectangle}{\param{wxCoord}{ x}, \param{wxCoord}{ y}, \param{wxCoord}{ width}, \param{wxCoord}{ height}, \param{double}{ radius = 20}}
+\func{void}{DrawRoundedRectangle}{\param{wxCoord}{ x}, \param{wxCoord}{ y}, \param{wxCoord}{ width}, \param{wxCoord}{ height}, \param{double}{ radius}}
Draws a rectangle with the given top left corner, and with the given
size. The corners are quarter-circles using the given radius. The
\membersection{wxDC::DrawSpline}\label{wxdcdrawspline}
+\func{void}{DrawSpline}{\param{int }{n}, \param{wxPoint }{points[]}}
+
+Draws a spline between all given control points, using the current
+pen.
+
\func{void}{DrawSpline}{\param{wxList *}{points}}
Draws a spline between all given control points, using the current
-pen. Doesn't delete the wxList and contents. The spline is drawn
-using a series of lines, using an algorithm taken from the X drawing
-program `XFIG'.
+pen. Doesn't delete the wxList and contents.
\func{void}{DrawSpline}{\param{wxCoord}{ x1}, \param{wxCoord}{ y1}, \param{wxCoord}{ x2}, \param{wxCoord}{ y2}, \param{wxCoord}{ x3}, \param{wxCoord}{ y3}}
Ends a document (only relevant when outputting to a printer).
-\membersection{wxDC::EndDrawing}\label{wxdcenddrawing}
-
-\func{void}{EndDrawing}{\void}
-
-Allows optimization of drawing code under MS Windows. Enclose
-drawing primitives between {\bf BeginDrawing} and {\bf EndDrawing}\rtfsp
-calls.
-
-
\membersection{wxDC::EndPage}\label{wxdcendpage}
\func{void}{EndPage}{\void}
\membersection{wxDC::GetBackground}\label{wxdcgetbackground}
-\func{wxBrush\&}{GetBackground}{\void}
-
\constfunc{const wxBrush\&}{GetBackground}{\void}
Gets the brush used for painting the background (see \helpref{wxDC::SetBackground}{wxdcsetbackground}).
\membersection{wxDC::GetBrush}\label{wxdcgetbrush}
-\func{wxBrush\&}{GetBrush}{\void}
-
\constfunc{const wxBrush\&}{GetBrush}{\void}
Gets the current brush (see \helpref{wxDC::SetBrush}{wxdcsetbrush}).
\membersection{wxDC::GetFont}\label{wxdcgetfont}
-\func{wxFont\&}{GetFont}{\void}
-
\constfunc{const wxFont\&}{GetFont}{\void}
-Gets the current font (see \helpref{wxDC::SetFont}{wxdcsetfont}).
+Gets the current font. Notice that even although each device context object has
+some default font after creation, this method would return a \texttt{wxNullFont}
+initially and only after calling \helpref{wxDC::SetFont}{wxdcsetfont} a valid
+font is returned.
\membersection{wxDC::GetLogicalFunction}\label{wxdcgetlogicalfunction}
Gets the {\it mapping mode} for the device context (see \helpref{wxDC::SetMapMode}{wxdcsetmapmode}).
-\membersection{wxDC::GetOptimization}\label{wxdcgetoptimization}
-
-\func{bool}{GetOptimization}{\void}
-
-Returns true if device context optimization is on.
-See \helpref{wxDC::SetOptimization}{wxsetoptimization} for details.
-
-
\membersection{wxDC::GetPartialTextExtents}\label{wxdcgetpartialtextextents}
\constfunc{bool}{GetPartialTextExtents}{\param{const wxString\& }{text},
\param{wxArrayInt\& }{widths}}
-Fills the {\it widths} array with the widths from the begining of
-{\it text} to the coresponding character of {\it text}. The generic
+Fills the {\it widths} array with the widths from the beginning of
+{\it text} to the corresponding character of {\it text}. The generic
version simply builds a running total of the widths of each character
using \helpref{GetTextExtent}{wxdcgettextextent}, however if the
various platforms have a native API function that is faster or more
-accurate than the generic implementaiton then it should be used
+accurate than the generic implementation then it should be used
instead.
\pythonnote{This method only takes the {\it text} parameter and
returns a Python list of integers.}
-\membersection{wxDC::GetPen}\label{wxdcgetpen}
-\func{wxPen\&}{GetPen}{\void}
+\membersection{wxDC::GetPen}\label{wxdcgetpen}
\constfunc{const wxPen\&}{GetPen}{\void}
\func{bool}{GetPixel}{\param{wxCoord}{ x}, \param{wxCoord}{ y}, \param{wxColour *}{colour}}
-Sets {\it colour} to the colour at the specified location. Windows only; an X implementation
-is being worked on. Not available for wxPostScriptDC or wxMetafileDC.
+Gets in {\it colour} the colour at the specified location.
+Not available for wxPostScriptDC or wxMetafileDC.
+
+Note that setting a pixel can be done using \helpref{DrawPoint}{wxdcdrawpoint}.
\pythonnote{For wxPython the wxColour value is returned and is not
required as a parameter.}
\perlnote{This method only takes the parameters {\tt x} and {\tt y} and returns
a Wx::Colour value}
+\membersection{wxDC::GetPPI}\label{wxdcgetppi}
+
+\constfunc{wxSize}{GetPPI}{\void}
+
+Returns the resolution of the device in pixels per inch.
\membersection{wxDC::GetSize}\label{wxdcgetsize}
-\func{void}{GetSize}{\param{wxCoord *}{width}, \param{wxCoord *}{height}}
+\constfunc{void}{GetSize}{\param{wxCoord *}{width}, \param{wxCoord *}{height}}
-For a PostScript device context, this gets the maximum size of graphics
-drawn so far on the device context.
+\constfunc{wxSize}{GetSize}{\void}
-For a Windows printer device context, this gets the horizontal and vertical
-resolution. It can be used to scale graphics to fit the page when using
-a Windows printer device context. For example, if {\it maxX} and {\it maxY}\rtfsp
+This gets the horizontal and vertical resolution in device units. It can be used to scale graphics to fit the page.
+For example, if {\it maxX} and {\it maxY}\rtfsp
represent the maximum horizontal and vertical `pixel' values used in your
application, the following code will scale the graphic to fit on the
printer page:
\end{twocollist}
}}
+\membersection{wxDC::GetSizeMM}\label{wxdcgetsizemm}
-\membersection{wxDC::GetTextBackground}\label{wxdcgettextbackground}
+\constfunc{void}{GetSizeMM}{\param{wxCoord *}{width}, \param{wxCoord *}{height}}
+
+\constfunc{wxSize}{GetSizeMM}{\void}
-\func{wxColour\&}{GetTextBackground}{\void}
+Returns the horizontal and vertical resolution in millimetres.
+
+\membersection{wxDC::GetTextBackground}\label{wxdcgettextbackground}
\constfunc{const wxColour\&}{GetTextBackground}{\void}
descender, and {\it externalLeading} is any extra vertical space added
to the font by the font designer (usually is zero).
-The optional parameter {\it font} specifies an alternative
-to the currently selected font: but note that this does not
-yet work under Windows, so you need to set a font for
-the device context first.
+If the optional parameter {\it font} is specified and valid, then it is used
+for the text extent calculation. Otherwise the currently selected font is.
See also \helpref{wxFont}{wxfont}, \helpref{wxDC::SetFont}{wxdcsetfont}.
\membersection{wxDC::GetTextForeground}\label{wxdcgettextforeground}
-\func{wxColour\&}{GetTextForeground}{\void}
-
\constfunc{const wxColour\&}{GetTextForeground}{\void}
Gets the current text foreground colour (see \helpref{wxDC::SetTextForeground}{wxdcsettextforeground}).
-
\membersection{wxDC::GetUserScale}\label{wxdcgetuserscale}
\func{void}{GetUserScale}{\param{double}{ *x}, \param{double}{ *y}}
array {\tt ( x, y )}}
+\membersection{wxDC::GradientFillConcentric}\label{wxdcgradientfillconcentric}
+
+\func{void}{GradientFillConcentric}{\param{const wxRect\&}{ rect}, \param{const wxColour\&}{ initialColour}, \param{const wxColour\&}{ destColour}}
+
+\func{void}{GradientFillConcentric}{\param{const wxRect\&}{ rect}, \param{const wxColour\&}{ initialColour}, \param{const wxColour\&}{ destColour}, \param{const wxPoint\& }{circleCenter}}
+
+Fill the area specified by rect with a radial gradient, starting from
+\arg{initialColour} at the centre of the circle and fading to \arg{destColour}
+on the circle outside.
+
+\arg{circleCenter} are the relative coordinates of centre of the circle in
+the specified \arg{rect}. If not specified, the cercle is placed at the
+centre of rect.
+
+\textbf{Note: } Currently this function is very slow, don't use it for
+real-time drawing.
+
+
+\membersection{wxDC::GradientFillLinear}\label{wxdcgradientfilllinear}
+
+\func{void}{GradientFillLinear}{\param{const wxRect\&}{ rect}, \param{const wxColour\&}{ initialColour}, \param{const wxColour\&}{ destColour}, \param{wxDirection}{ nDirection = wxEAST}}
+
+Fill the area specified by \arg{rect} with a linear gradient, starting from
+\arg{initialColour} and eventually fading to \arg{destColour}. The
+\arg{nDirection} specifies the direction of the colour change, default is to
+use \arg{initialColour} on the left part of the rectangle and
+\arg{destColour} on the right one.
+
+
\membersection{wxDC::LogicalToDeviceX}\label{wxdclogicaltodevicex}
\func{wxCoord}{LogicalToDeviceX}{\param{wxCoord}{ x}}
\param{bool}{ yBottomUp}}
Sets the x and y axis orientation (i.e., the direction from lowest to
-highest values on the axis). The default orientation is the natural
-orientation, e.g. x axis from left to right and y axis from bottom up.
+highest values on the axis). The default orientation is
+x axis from left to right and y axis from top down.
\wxheading{Parameters}
bottom up orientation, false to invert it.}
-\membersection{wxDC::SetDeviceOrigin}\label{wxdcsetdeviceorigin}
-
-\func{void}{SetDeviceOrigin}{\param{wxCoord}{ x}, \param{wxCoord}{ y}}
-
-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.
-
-
\membersection{wxDC::SetBackground}\label{wxdcsetbackground}
\func{void}{SetBackground}{\param{const wxBrush\& }{brush}}
whether text will be drawn with a background colour or not.
+\membersection{wxDC::SetBrush}\label{wxdcsetbrush}
+
+\func{void}{SetBrush}{\param{const wxBrush\& }{brush}}
+
+Sets the current brush for the DC.
+
+If the argument is wxNullBrush, the current brush is selected out of the device
+context, and the original brush restored, allowing the current brush to
+be destroyed safely.
+
+See also \helpref{wxBrush}{wxbrush}.
+
+See also \helpref{wxMemoryDC}{wxmemorydc} for the interpretation of colours
+when drawing into a monochrome bitmap.
+
+
\membersection{wxDC::SetClippingRegion}\label{wxdcsetclippingregion}
\func{void}{SetClippingRegion}{\param{wxCoord}{ x}, \param{wxCoord}{ y}, \param{wxCoord}{ width}, \param{wxCoord}{ height}}
\helpref{wxDC::DestroyClippingRegion}{wxdcdestroyclippingregion}, \helpref{wxRegion}{wxregion}
-\membersection{wxDC::SetPalette}\label{wxdcsetpalette}
-
-\func{void}{SetPalette}{\param{const wxPalette\& }{palette}}
-
-If this is a window DC or memory DC, assigns the given palette to the window
-or bitmap associated with the DC. If the argument is wxNullPalette, the current
-palette is selected out of the device context, and the original palette
-restored.
-
-See \helpref{wxPalette}{wxpalette} for further details.
-
-
-\membersection{wxDC::SetBrush}\label{wxdcsetbrush}
-
-\func{void}{SetBrush}{\param{const wxBrush\& }{brush}}
-
-Sets the current brush for the DC.
+\membersection{wxDC::SetDeviceOrigin}\label{wxdcsetdeviceorigin}
-If the argument is wxNullBrush, the current brush is selected out of the device
-context, and the original brush restored, allowing the current brush to
-be destroyed safely.
+\func{void}{SetDeviceOrigin}{\param{wxCoord}{ x}, \param{wxCoord}{ y}}
-See also \helpref{wxBrush}{wxbrush}.
+Sets the device origin (i.e., the origin in pixels after scaling has been
+applied).
-See also \helpref{wxMemoryDC}{wxmemorydc} for the interpretation of colours
-when drawing into a monochrome bitmap.
+This function may be useful in Windows printing
+operations for placing a graphic on a page.
\membersection{wxDC::SetFont}\label{wxdcsetfont}
Windows, scalable TrueType fonts are always used; in X, results depend
on availability of fonts, but usually a reasonable match is found.
-Note that the coordinate origin should ideally be selectable, but for
-now is always at the top left of the screen/printer.
+The coordinate origin is always at the top left of the screen/printer.
-Drawing to a Windows printer device context under UNIX
-uses the current mapping mode, but mapping mode is currently ignored for
-PostScript output.
+Drawing to a Windows printer device context uses the current mapping mode,
+but mapping mode is currently ignored for PostScript output.
The mapping mode can be one of the following:
\end{twocollist}
-\membersection{wxDC::SetOptimization}\label{wxsetoptimization}
+\membersection{wxDC::SetPalette}\label{wxdcsetpalette}
-\func{void}{SetOptimization}{\param{bool }{optimize}}
+\func{void}{SetPalette}{\param{const wxPalette\& }{palette}}
-If {\it optimize} is true (the default), this function sets optimization mode on.
-This currently means that under X, the device context will not try to set a pen or brush
-property if it is known to be set already. This approach can fall down
-if non-wxWindows code is using the same device context or window, for example
-when the window is a panel on which the windowing system draws panel items.
-The wxWindows device context 'memory' will now be out of step with reality.
+If this is a window DC or memory DC, assigns the given palette to the window
+or bitmap associated with the DC. If the argument is wxNullPalette, the current
+palette is selected out of the device context, and the original palette
+restored.
-Setting optimization off, drawing, then setting it back on again, is a trick
-that must occasionally be employed.
+See \helpref{wxPalette}{wxpalette} for further details.
\membersection{wxDC::SetPen}\label{wxdcsetpen}
\func{bool}{StartDoc}{\param{const wxString\& }{message}}
Starts a document (only relevant when outputting to a printer).
-Message is a message to show whilst printing.
+Message is a message to show while printing.
\membersection{wxDC::StartPage}\label{wxdcstartpage}
\func{bool}{StartPage}{\void}
Starts a document page (only relevant when outputting to a printer).
-
-\section{\class{wxDCClipper}}\label{wxdcclipper}
-
-This is a small helper class which sets the specified to its constructor
-clipping region and then automatically destroys it in its destructor. Using
-it ensures that unwanted clipping region is not left set on the DC.
-
-\wxheading{Derived from}
-
-No base class
-
-\wxheading{Include files}
-
-<wx/dc.h>
-
-\wxheading{See also}
-
-\helpref{wxDC}{wxdc}
-
-\latexignore{\rtfignore{\wxheading{Members}}}
-
-
-\membersection{wxDCClipper::wxDCClipper}
-
-\func{}{wxDCClipper}{\param{wxDC\& }{dc}, \param{wxCoord }{x},\param{wxCoord }{y},\param{wxCoord }{w},\param{wxCoord }{h},}
-
-\func{}{wxDCClipper}{\param{wxDC\& }{dc}, \param{const wxRect\&}{ rect}}
-
-Constructor: sets the the clipping region for the given device context to the
-specified rectangle.
-
-
-\membersection{wxDCClipper::\destruct{wxDCClipper}}
-
-\func{}{\destruct{wxDCClipper}}{\void}
-
-Destructor: destroys the clipping region set in the constructor.
-
projects / wxWidgets.git / blobdiff