X-Git-Url: https://git.saurik.com/wxWidgets.git/blobdiff_plain/717ba4898b26dc88bdc1fa73f4a05626561647d6..8fa8d158bd6aadab98b40fc85a30425ada252ff4:/docs/latex/wx/dc.tex diff --git a/docs/latex/wx/dc.tex b/docs/latex/wx/dc.tex index 2ac964b21f..b74a3341e9 100644 --- a/docs/latex/wx/dc.tex +++ b/docs/latex/wx/dc.tex @@ -6,8 +6,10 @@ so a window can have a device context associated with it, and a printer also has 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 @@ -31,36 +33,6 @@ them. \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}, @@ -193,6 +165,15 @@ wxUSE\_DC\_CACHEING preprocessor symbol for portability. \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}} @@ -477,7 +458,7 @@ which is. \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 @@ -495,12 +476,15 @@ the rectangle. \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}} @@ -556,15 +540,6 @@ wxUSE\_DC\_CACHEING preprocessor symbol for portability. 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} @@ -647,7 +622,10 @@ rectangle are returned as a tuple.} \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} @@ -664,25 +642,17 @@ Gets the current logical function (see \helpref{wxDC::SetLogicalFunction}{wxdcse 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 @@ -700,9 +670,11 @@ Gets the current pen (see \helpref{wxDC::SetPen}{wxdcsetpen}). \func{bool}{GetPixel}{\param{wxCoord}{ x}, \param{wxCoord}{ y}, \param{wxColour *}{colour}} -Sets {\it colour} to the colour at the specified location. +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.} @@ -778,10 +750,8 @@ 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 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}. @@ -816,6 +786,35 @@ Gets the current user scale factor (set by \helpref{SetUserScale}{wxdcsetusersca 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}} @@ -903,8 +902,8 @@ doesn't contain anything. \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} @@ -1059,21 +1058,6 @@ The mapping mode can be one of the following: \end{twocollist} -\membersection{wxDC::SetOptimization}\label{wxsetoptimization} - -\func{void}{SetOptimization}{\param{bool }{optimize}} - -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-wxWidgets 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 wxWidgets device context 'memory' will now be out of step with reality. - -Setting optimization off, drawing, then setting it back on again, is a trick -that must occasionally be employed. - - \membersection{wxDC::SetPalette}\label{wxdcsetpalette} \func{void}{SetPalette}{\param{const wxPalette\& }{palette}} @@ -1129,7 +1113,7 @@ Sets the user scaling factor, useful for applications which require \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} @@ -1140,9 +1124,9 @@ 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 +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 unwanted clipping region is not left set on the DC. +it ensures that an unwanted clipping region is not left set on the DC. \wxheading{Derived from} @@ -1165,7 +1149,7 @@ No base class \func{}{wxDCClipper}{\param{wxDC\& }{dc}, \param{const wxRect\&}{ rect}} -Constructor: sets the the clipping region for the given device context to the +Constructor: sets the clipping region for the given device context to the specified rectangle.