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}\label{wxdcctor}
-
-\func{}{wxDC}{\void}
-
-Constructor.
-
-
-\membersection{wxDC::\destruct{wxDC}}\label{wxdcdtor}
-
-\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},
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}
\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}
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}.
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}}
\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 DC to its constructor
-clipping region and then automatically destroys it in its destructor. Using
-it ensures that an 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}\label{wxdcclipperctor}
-
-\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 clipping region for the given device context to the
-specified rectangle.
-
-
-\membersection{wxDCClipper::\destruct{wxDCClipper}}\label{wxdcclipperdtor}
-
-\func{}{\destruct{wxDCClipper}}{\void}
-
-Destructor: destroys the clipping region set in the constructor.
-
projects / wxWidgets.git / blobdiff