Derived types of wxDC have documentation for specific features
only, so refer to this section for most device context information.
+% 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
+Please note that in addition to the versions of the methods documented here,
+there are also versions which accept single {\tt wxPoint} parameter instead of
+two {\tt wxCoord} ones or {\tt wxPoint} and {\tt wxSize} instead of four of
+them.
+
\wxheading{Derived from}
\helpref{wxObject}{wxobject}
\func{bool}{Blit}{\param{wxCoord}{ xdest}, \param{wxCoord}{ ydest}, \param{wxCoord}{ width}, \param{wxCoord}{ height},
\param{wxDC* }{source}, \param{wxCoord}{ xsrc}, \param{wxCoord}{ ysrc}, \param{int}{ logicalFunc = wxCOPY},
- \param{bool }{useMask = FALSE}}
+ \param{bool }{useMask = false}, \param{wxCoord}{ xsrcMask = -1}, \param{wxCoord}{ ysrcMask = -1}}
Copy from a source DC to this DC, specifying the destination
-coordinates, size of area to copy, source DC, source coordinates, and
-logical function.
+coordinates, size of area to copy, source DC, source coordinates,
+logical function, whether to use a bitmap mask, and mask source position.
\wxheading{Parameters}
\docparam{logicalFunc}{Logical function to use: see \helpref{wxDC::SetLogicalFunction}{wxdcsetlogicalfunction}.}
-\docparam{useMask}{If TRUE, Blit does a transparent blit using the mask that is associated with the bitmap
-selected into the source device context. The Windows implementation does the following:
+\docparam{useMask}{If true, Blit does a transparent blit using the mask that is associated with the bitmap
+selected into the source device context. The Windows implementation does the following if MaskBlt cannot be used:
\begin{enumerate}
\item Creates a temporary bitmap and copies the destination area into it.
This sequence of operations ensures that the source's transparent area need not be black,
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
+or the explicit mask blitting code above is used, by using \helpref{wxSystemOptions}{wxsystemoptions} and
+setting the {\bf no-maskblt} option to 1.
+
}
+\docparam{xsrcMask}{Source x position on the mask. If both xsrcMask and ysrcMask are -1, xsrc and ysrc
+will be assumed for the mask source position. Currently only implemented on Windows.}
+
+\docparam{ysrcMask}{Source y position on the mask. If both xsrcMask and ysrcMask are -1, xsrc and ysrc
+will be assumed for the mask source position. Currently only implemented on Windows.}
+
+
\wxheading{Remarks}
There is partial support for Blit in wxPostScriptDC, under X.
\helpref{wxMemoryDC}{wxmemorydc}, \helpref{wxBitmap}{wxbitmap}, \helpref{wxMask}{wxmask}
+\begin{comment}
+\membersection{wxDC::CacheEnabled}\label{wxdccacheenabled}
+
+\func{static bool}{CacheEnabled}{\void}
+
+On supported platforms (currently only Windows), returns true
+if the DC cache is enabled. The DC cache
+can speed up the \helpref{Blit}{wxdcblit} operation when
+drawing a large number of masked bitmaps.
+
+If using the cache functions in your code, please test for the
+wxUSE\_DC\_CACHEING preprocessor symbol for portability.
+
+\wxheading{See also}
+
+\helpref{wxDC::EnableCache}{wxdcenablecache}, \helpref{wxDC::ClearCache}
+\end{comment}
+
+\membersection{wxDC::CalcBoundingBox}\label{wxdccalcboundingbox}
+
+\func{void}{CalcBoundingBox}{\param{wxCoord }{x}, \param{wxCoord }{y}}
+
+Adds the specified point to the bounding box which can be retrieved with
+\helpref{MinX}{wxdcminx}, \helpref{MaxX}{wxdcmaxx} and
+\helpref{MinY}{wxdcminy}, \helpref{MaxY}{wxdcmaxy} functions.
+
+\wxheading{See also}
+
+\helpref{ResetBoundingBox}{wxdcresetboundingbox}
+
\membersection{wxDC::Clear}\label{wxdcclear}
\func{void}{Clear}{\void}
Clears the device context using the current background brush.
+\begin{comment}
+\membersection{wxDC::ClearCache}\label{wxdcclearcache}
+
+\func{static void}{ClearCache}{\void}
+
+On supported platforms (currently only Windows), clears
+the contents of the DC cache (one bitmap and two Windows device contexts). The DC cache
+can speed up the \helpref{Blit}{wxdcblit} operation when
+drawing a large number of masked bitmaps. You should
+call ClearCache at the end of length DC operations if you wish to only use
+the cache transiently; you should also call it as your application exits.
+
+If using the cache functions in your code, please test for the
+wxUSE\_DC\_CACHEING preprocessor symbol for portability.
+
+\wxheading{See also}
+
+\helpref{wxDC::EnableCache}{wxdcenablecache}, \helpref{wxDC::CacheEnabled}
+\end{comment}
+
\membersection{wxDC::CrossHair}\label{wxdccrosshair}
\func{void}{CrossHair}{\param{wxCoord}{ x}, \param{wxCoord}{ y}}
\func{wxCoord}{DeviceToLogicalXRel}{\param{wxCoord}{ x}}
Convert device X coordinate to relative logical coordinate, using the current
-mapping mode. Use this function for converting a width, for example.
+mapping mode but ignoring the x axis orientation.
+Use this function for converting a width, for example.
\membersection{wxDC::DeviceToLogicalY}\label{wxdcdevicetologicaly}
\func{wxCoord}{DeviceToLogicalYRel}{\param{wxCoord}{ y}}
Convert device Y coordinate to relative logical coordinate, using the current
-mapping mode. Use this function for converting a height, for example.
+mapping mode but ignoring the y axis orientation.
+Use this function for converting a height, for example.
\membersection{wxDC::DrawArc}\label{wxdcdrawarc}
\func{void}{DrawBitmap}{\param{const wxBitmap\&}{ bitmap}, \param{wxCoord}{ x}, \param{wxCoord}{ y}, \param{bool}{ transparent}}
-Draw a bitmap on the device context at the specified point. If {\it transparent} is TRUE and the bitmap has
+Draw a bitmap on the device context at the specified point. If {\it transparent} is true and the bitmap has
a transparency mask, the bitmap will be drawn transparently.
When drawing a mono-bitmap, the current text foreground colour will be used to draw the foreground
of the bitmap (all bits set to 1), and the current text background colour to draw the background
-(all bits set to 0). See also \helpref{SetTextForeground}{wxdcsettextforeground},
+(all bits set to 0). See also \helpref{SetTextForeground}{wxdcsettextforeground},
\helpref{SetTextBackground}{wxdcsettextbackground} and \helpref{wxMemoryDC}{wxmemorydc}.
+\membersection{wxDC::DrawCheckMark}\label{wxdcdrawcheckmark}
+
+\func{void}{DrawCheckMark}{\param{wxCoord}{ x}, \param{wxCoord}{ y}, \param{wxCoord}{ width}, \param{wxCoord}{ height}}
+
+\func{void}{DrawCheckMark}{\param{const wxRect \&}{rect}}
+
+Draws a check mark inside the given rectangle.
+
+\membersection{wxDC::DrawCircle}\label{wxdcdrawcircle}
+
+\func{void}{DrawCircle}{\param{wxCoord}{ x}, \param{wxCoord}{ y}, \param{wxCoord}{ radius}}
+
+\func{void}{DrawCircle}{\param{const wxPoint\&}{ pt}, \param{wxCoord}{ radius}}
+
+Draws a circle with the given centre and radius.
+
+\wxheading{See also}
+
+\helpref{DrawEllipse}{wxdcdrawellipse}
+
\membersection{wxDC::DrawEllipse}\label{wxdcdrawellipse}
\func{void}{DrawEllipse}{\param{wxCoord}{ x}, \param{wxCoord}{ y}, \param{wxCoord}{ width}, \param{wxCoord}{ height}}
-Draws an ellipse contained in the rectangle with the given top left corner, and with the
-given size. The current pen is used for the outline and the current brush for
-filling the shape.
+\func{void}{DrawEllipse}{\param{const wxPoint\&}{ pt}, \param{const wxSize\&}{ size}}
+
+\func{void}{DrawEllipse}{\param{const wxRect\&}{ rect}}
+
+Draws an ellipse contained in the rectangle specified either with the given top
+left corner and the given size or directly. The current pen is used for the
+outline and the current brush for filling the shape.
+
+\wxheading{See also}
+
+\helpref{DrawCircle}{wxdcdrawcircle}
\membersection{wxDC::DrawEllipticArc}\label{wxdcdrawellipticarc}
\param{double}{ start}, \param{double}{ end}}
Draws an arc of an ellipse. The current pen is used for drawing the arc and
-the current brush is used for drawing the pie. This function is currently only available for
-X window and PostScript device contexts.
+the current brush is used for drawing the pie.
{\it x} and {\it y} specify the x and y coordinates of the upper-left corner of the rectangle that contains
the ellipse.
\func{void}{DrawLine}{\param{wxCoord}{ x1}, \param{wxCoord}{ y1}, \param{wxCoord}{ x2}, \param{wxCoord}{ y2}}
Draws a line from the first point to the second. The current pen is used
-for drawing the line.
+for drawing the line. Note that the point $(x2, y2)$ is {\emph not} part of the
+line and is not drawn by this function (this is consistent with the behaviour
+of many other toolkits).
\membersection{wxDC::DrawLines}\label{wxdcdrawlines}
\pythonnote{The wxPython version of this method accepts a Python list
of wxPoint objects.}
+\perlnote{The wxPerl version of this method accepts
+ as its first parameter a reference to an array
+ of wxPoint objects.}
+
\membersection{wxDC::DrawPolygon}\label{wxdcdrawpolygon}
\func{void}{DrawPolygon}{\param{int}{ n}, \param{wxPoint}{ points[]}, \param{wxCoord}{ xoffset = 0}, \param{wxCoord}{ yoffset = 0},\\
\pythonnote{The wxPython version of this method accepts a Python list
of wxPoint objects.}
+\perlnote{The wxPerl version of this method accepts
+ as its first parameter a reference to an array
+ of wxPoint objects.}
+
\membersection{wxDC::DrawPoint}\label{wxdcdrawpoint}
\func{void}{DrawPoint}{\param{wxCoord}{ x}, \param{wxCoord}{ y}}
Draws the text rotated by {\it angle} degrees.
+{\bf NB:} Under Win9x only TrueType fonts can be drawn by this function. In
+particular, a font different from {\tt wxNORMAL\_FONT} should be used as the
+latter is not a TrueType font. {\tt wxSWISS\_FONT} is an example of a font
+which is.
+
\wxheading{See also}
\helpref{DrawText}{wxdcdrawtext}
\pythonnote{The wxPython version of this method accepts a Python list
of wxPoint objects.}
+\perlnote{The wxPerl version of this method accepts a reference to an array
+ of wxPoint objects.}
+
\membersection{wxDC::DrawText}\label{wxdcdrawtext}
\func{void}{DrawText}{\param{const wxString\& }{text}, \param{wxCoord}{ x}, \param{wxCoord}{ y}}
to get the dimensions of a text string, which can be used to position the
text more precisely.
+{\bf NB:} under wxGTK the current
+\helpref{logical function}{wxdcgetlogicalfunction} is used by this function
+but it is ignored by wxMSW. Thus, you should avoid using logical functions
+with this function in portable programs.
+
+\begin{comment}
+\membersection{wxDC::EnableCache}\label{wxdcenablecache}
+
+\func{static void}{EnableCache}{\param{bool}{ enableCache}}
+
+On supported platforms (currently only Windows), enables the DC cache
+which can speed up the \helpref{Blit}{wxdcblit} operation when
+drawing a large number of masked bitmaps.
+
+If using the cache functions in your code, please test for the
+wxUSE\_DC\_CACHEING preprocessor symbol for portability.
+
+\wxheading{See also}
+
+\helpref{wxDC::CacheEnabled}{wxdccacheenabled}, \helpref{wxDC::ClearCache}
+\end{comment}
+
\membersection{wxDC::EndDoc}\label{wxdcenddoc}
\func{void}{EndDoc}{\void}
\membersection{wxDC::FloodFill}\label{wxdcfloodfill}
-\func{void}{FloodFill}{\param{wxCoord}{ x}, \param{wxCoord}{ y}, \param{wxColour *}{colour}, \param{int}{ style=wxFLOOD\_SURFACE}}
+\func{bool}{FloodFill}{\param{wxCoord}{ x}, \param{wxCoord}{ y}, \param{const wxColour\&}{ colour}, \param{int}{ style=wxFLOOD\_SURFACE}}
-Flood fills the device context starting from the given point, in the given colour,
-and using a style:
+Flood fills the device context starting from the given point, using
+the {\it current brush colour}, and using a style:
\begin{itemize}\itemsep=0pt
\item wxFLOOD\_SURFACE: the flooding occurs until a colour other than the given colour is encountered.
\item wxFLOOD\_BORDER: the area to be flooded is bounded by the given colour.
\end{itemize}
-{\it Note:} this function is available in MS Windows only.
+Returns false if the operation failed.
+
+{\it 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.
\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::GetBackgroundMode}\label{wxdcgetbackgroundmode}
+
+\constfunc{int}{GetBackgroundMode}{\void}
+
+Returns the current background mode: {\tt wxSOLID} or {\tt wxTRANSPARENT}.
+
+\wxheading{See also}
+
+\helpref{SetBackgroundMode}{wxdcsetbackgroundmode}
+
\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::GetCharHeight}\label{wxdcgetcharheight}
\pythonnote{No arguments are required and the four values defining the
rectangle are returned as a tuple.}
+\perlnote{This method takes no arguments and returns a four element list
+{\tt ( x, y, width, height )}}
+
\membersection{wxDC::GetFont}\label{wxdcgetfont}
\func{wxFont\&}{GetFont}{\void}
+\constfunc{const wxFont\&}{GetFont}{\void}
+
Gets the current font (see \helpref{wxDC::SetFont}{wxdcsetfont}).
\membersection{wxDC::GetLogicalFunction}\label{wxdcgetlogicalfunction}
\func{bool}{GetOptimization}{\void}
-Returns TRUE if device context optimization is on.
+Returns true if device context optimization is on.
See \helpref{wxDC::SetOptimization}{wxsetoptimization} for details.
\membersection{wxDC::GetPen}\label{wxdcgetpen}
\func{wxPen\&}{GetPen}{\void}
+\constfunc{const wxPen\&}{GetPen}{\void}
+
Gets the current pen (see \helpref{wxDC::SetPen}{wxdcsetpen}).
\membersection{wxDC::GetPixel}\label{wxdcgetpixel}
\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::GetSize}\label{wxdcgetsize}
\func{void}{GetSize}{\param{wxCoord *}{width}, \param{wxCoord *}{height}}
\end{twocollist}}
}
+\perlnote{In place of a single overloaded method, wxPerl uses:\par
+\indented{2cm}{\begin{twocollist}
+\twocolitem{{\bf GetSize()}}{Returns a Wx::Size}
+\twocolitem{{\bf GetSizeWH()}}{Returns a 2-element list
+ {\tt ( width, height )}}
+\end{twocollist}
+}}
+
\membersection{wxDC::GetTextBackground}\label{wxdcgettextbackground}
\func{wxColour\&}{GetTextBackground}{\void}
+\constfunc{const wxColour\&}{GetTextBackground}{\void}
+
Gets the current text background colour (see \helpref{wxDC::SetTextBackground}{wxdcsettextbackground}).
\membersection{wxDC::GetTextExtent}\label{wxdcgettextextent}
\end{twocollist}}
}
+\perlnote{In wxPerl this method is implemented as
+ {\bf GetTextExtent( string, font = undef )} returning a four element
+ array {\tt ( width, height, descent, externalLeading )}
+}
+
\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}).
Gets the current user scale factor (set by \helpref{SetUserScale}{wxdcsetuserscale}).
+\perlnote{In wxPerl this method takes no arguments and return a two element
+ array {\tt ( x, y )}}
\membersection{wxDC::LogicalToDeviceX}\label{wxdclogicaltodevicex}
\func{wxCoord}{LogicalToDeviceXRel}{\param{wxCoord}{ x}}
Converts logical X coordinate to relative device coordinate, using the current
-mapping mode. Use this for converting a width, for example.
+mapping mode but ignoring the x axis orientation.
+Use this for converting a width, for example.
\membersection{wxDC::LogicalToDeviceY}\label{wxdclogicaltodevicey}
\func{wxCoord}{LogicalToDeviceYRel}{\param{wxCoord}{ y}}
Converts logical Y coordinate to relative device coordinate, using the current
-mapping mode. Use this for converting a height, for example.
+mapping mode but ignoring the y axis orientation.
+Use this for converting a height, for example.
\membersection{wxDC::MaxX}\label{wxdcmaxx}
\func{bool}{Ok}{\void}
-Returns TRUE if the DC is ok to use.
+Returns true if the DC is ok to use.
+
+\membersection{wxDC::ResetBoundingBox}\label{wxdcresetboundingbox}
+
+\func{void}{ResetBoundingBox}{\void}
+
+Resets the bounding box: after a call to this function, the bounding box
+doesn't contain anything.
+
+\wxheading{See also}
+
+\helpref{CalcBoundingBox}{wxdccalcboundingbox}
+
+\membersection{wxDC::SetAxisOrientation}\label{wxdcsetaxisorientation}
+
+\func{void}{SetAxisOrientation}{\param{bool}{ xLeftRight},
+ \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.
+
+\wxheading{Parameters}
+
+\docparam{xLeftRight}{True to set the x axis orientation to the natural
+left to right orientation, false to invert it.}
+
+\docparam{yBottomUp}{True to set the y axis orientation to the natural
+bottom up orientation, false to invert it.}
\membersection{wxDC::SetDeviceOrigin}\label{wxdcsetdeviceorigin}
\func{void}{SetClippingRegion}{\param{wxCoord}{ x}, \param{wxCoord}{ y}, \param{wxCoord}{ width}, \param{wxCoord}{ height}}
+\func{void}{SetClippingRegion}{\param{const wxPoint\& }{pt}, \param{const wxSize\& }{sz}}
+
+\func{void}{SetClippingRegion}{\param{const wxRect\&}{ rect}}
+
\func{void}{SetClippingRegion}{\param{const wxRegion\&}{ region}}
-Sets the clipping region for the DC. 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.
+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
+\helpref{DestroyClippingRegion}{wxdcdestroyclippingregion} if you want to set
+the clipping region exactly to the region specified.
+
+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.
\wxheading{See also}
\func{void}{SetFont}{\param{const wxFont\& }{font}}
-Sets the current font for the DC.
-
-If the argument is wxNullFont, the current font is selected out of the device
-context, and the original font restored, allowing the current font to
-be destroyed safely.
+Sets the current font for the DC. It must be a valid font, in particular you
+should not pass {\tt wxNullFont} to this method.
See also \helpref{wxFont}{wxfont}.
in X, text drawing isn't handled consistently with the mapping mode; a
font is always specified in point size. However, setting the {\it
user scale} (see \helpref{wxDC::SetUserScale}{wxdcsetuserscale}) scales the text appropriately. In
-Windows, scaleable TrueType fonts are always used; in X, results depend
+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
\func{void}{SetOptimization}{\param{bool }{optimize}}
-If {\it optimize} is TRUE (the default), this function sets optimization mode on.
+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
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.
+