dc.tex

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\rtfsp{\it string} is the text string to measure, {\it descent} is the
dimension from the baseline of the font to the bottom of the
descender, and {\it externalLeading} is any extra vertical space added
to the font by the font designer (usually is zero).

The text extent is returned in {\it w} and {\it h} pointers (first form) or as
a \helpref{wxSize}{wxsize} object (second form).

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.

Note that this function only works with single-line strings.

\wxheading{See also}

\helpref{wxFont}{wxfont},\rtfsp
\helpref{wxDC::SetFont}{wxdcsetfont},\rtfsp
\helpref{wxDC::GetPartialTextExtents}{wxdcgetpartialtextextents},\rtfsp
\helpref{wxDC::GetMultiLineTextExtent}{wxdcgetmultilinetextextent}

\pythonnote{The following methods are implemented in wxPython:\par
\indented{2cm}{\begin{twocollist}
\twocolitem{{\bf GetTextExtent(string)}}{Returns a 2-tuple, (width, height)}
\twocolitem{{\bf GetFullTextExtent(string, font=NULL)}}{Returns a
4-tuple, (width, height, descent, externalLeading) }
\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}

\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}}

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::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}}

Converts logical X coordinate to device coordinate, using the current
mapping mode.


\membersection{wxDC::LogicalToDeviceXRel}\label{wxdclogicaltodevicexrel}

\func{wxCoord}{LogicalToDeviceXRel}{\param{wxCoord}{ x}}

Converts logical X coordinate to relative device coordinate, using the current
mapping mode but ignoring the x axis orientation.
Use this for converting a width, for example.


\membersection{wxDC::LogicalToDeviceY}\label{wxdclogicaltodevicey}

\func{wxCoord}{LogicalToDeviceY}{\param{wxCoord}{ y}}

Converts logical Y coordinate to device coordinate, using the current
mapping mode.


\membersection{wxDC::LogicalToDeviceYRel}\label{wxdclogicaltodeviceyrel}

\func{wxCoord}{LogicalToDeviceYRel}{\param{wxCoord}{ y}}

Converts logical Y coordinate to relative device coordinate, using the current
mapping mode but ignoring the y axis orientation.
Use this for converting a height, for example.


\membersection{wxDC::MaxX}\label{wxdcmaxx}

\func{wxCoord}{MaxX}{\void}

Gets the maximum horizontal extent used in drawing commands so far.


\membersection{wxDC::MaxY}\label{wxdcmaxy}

\func{wxCoord}{MaxY}{\void}

Gets the maximum vertical extent used in drawing commands so far.


\membersection{wxDC::MinX}\label{wxdcminx}

\func{wxCoord}{MinX}{\void}

Gets the minimum horizontal extent used in drawing commands so far.


\membersection{wxDC::MinY}\label{wxdcminy}

\func{wxCoord}{MinY}{\void}

Gets the minimum vertical extent used in drawing commands so far.


\membersection{wxDC::IsOk}\label{wxdcisok}

\func{bool}{Ok}{\void}

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 
x axis from left to right and y axis from top down.

\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::SetBackground}\label{wxdcsetbackground}

\func{void}{SetBackground}{\param{const wxBrush\& }{brush}}

Sets the current background brush for the DC.


\membersection{wxDC::SetBackgroundMode}\label{wxdcsetbackgroundmode}

\func{void}{SetBackgroundMode}{\param{int}{ mode}}

{\it mode} may be one of wxSOLID and wxTRANSPARENT. This setting determines
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}}

\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 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}

\helpref{wxDC::DestroyClippingRegion}{wxdcdestroyclippingregion}, \helpref{wxRegion}{wxregion}


\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::SetFont}\label{wxdcsetfont}

\func{void}{SetFont}{\param{const wxFont\& }{font}}

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}.


\membersection{wxDC::SetLayoutDirection}\label{wxdcsetlayoutdirection}

\func{void}{SetLayoutDirection}{\param{wxLayoutDirection}{ dir}}

Sets the current layout direction for the device context. \arg{dir} may be either
\texttt{wxLayout\_Default}, \texttt{wxLayout\_LeftToRight} or \texttt{wxLayout\_RightToLeft}.

\wxheading{See also}

\helpref{GetLayoutDirection}{wxdcgetlayoutdirection}


\membersection{wxDC::SetLogicalFunction}\label{wxdcsetlogicalfunction}

\func{void}{SetLogicalFunction}{\param{int}{ function}}

Sets the current logical function for the device context.  This determines how
a source pixel (from a pen or brush colour, or source device context if
using \helpref{wxDC::Blit}{wxdcblit}) combines with a destination pixel in the
current device context.

The possible values
and their meaning in terms of source and destination pixel values are
as follows:

\begin{verbatim}
wxAND                 src AND dst
wxAND_INVERT          (NOT src) AND dst
wxAND_REVERSE         src AND (NOT dst)
wxCLEAR               0
wxCOPY                src
wxEQUIV               (NOT src) XOR dst
wxINVERT              NOT dst
wxNAND                (NOT src) OR (NOT dst)
wxNOR                 (NOT src) AND (NOT dst)
wxNO_OP               dst
wxOR                  src OR dst
wxOR_INVERT           (NOT src) OR dst
wxOR_REVERSE          src OR (NOT dst)
wxSET                 1
wxSRC_INVERT          NOT src
wxXOR                 src XOR dst
\end{verbatim}

The default is wxCOPY, which simply draws with the current colour.
The others combine the current colour and the background using a
logical operation.  wxINVERT is commonly used for drawing rubber bands or
moving outlines, since drawing twice reverts to the original colour.


\membersection{wxDC::SetMapMode}\label{wxdcsetmapmode}

\func{void}{SetMapMode}{\param{int}{ int}}

The {\it mapping mode} of the device context defines the unit of
measurement used to convert logical units to device units. Note that
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, scalable TrueType fonts are always used; in X, results depend
on availability of fonts, but usually a reasonable match is found.

The coordinate origin is always at the top left of the screen/printer.

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:

\begin{twocollist}\itemsep=0pt
\twocolitem{wxMM\_TWIPS}{Each logical unit is 1/20 of a point, or 1/1440 of
  an inch.}
\twocolitem{wxMM\_POINTS}{Each logical unit is a point, or 1/72 of an inch.}
\twocolitem{wxMM\_METRIC}{Each logical unit is 1 mm.}
\twocolitem{wxMM\_LOMETRIC}{Each logical unit is 1/10 of a mm.}
\twocolitem{wxMM\_TEXT}{Each logical unit is 1 pixel.}
\end{twocollist}


\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::SetPen}\label{wxdcsetpen}

\func{void}{SetPen}{\param{const wxPen\& }{pen}}

Sets the current pen for the DC.

If the argument is wxNullPen, the current pen is selected out of the device
context, and the original pen restored.

See also \helpref{wxMemoryDC}{wxmemorydc} for the interpretation of colours
when drawing into a monochrome bitmap.


\membersection{wxDC::SetTextBackground}\label{wxdcsettextbackground}

\func{void}{SetTextBackground}{\param{const wxColour\& }{colour}}

Sets the current text background colour for the DC.


\membersection{wxDC::SetTextForeground}\label{wxdcsettextforeground}

\func{void}{SetTextForeground}{\param{const wxColour\& }{colour}}

Sets the current text foreground colour for the DC.

See also \helpref{wxMemoryDC}{wxmemorydc} for the interpretation of colours
when drawing into a monochrome bitmap.


\membersection{wxDC::SetUserScale}\label{wxdcsetuserscale}

\func{void}{SetUserScale}{\param{double}{ xScale}, \param{double}{ yScale}}

Sets the user scaling factor, useful for applications which require
`zooming'.


\membersection{wxDC::StartDoc}\label{wxdcstartdoc}

\func{bool}{StartDoc}{\param{const wxString\& }{message}}

Starts a document (only relevant when outputting to a printer).
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).