wxWidgets/docs/latex/wx/palette.tex

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\section{\class{wxPalette}}\label{wxpalette}
A palette is a table that maps pixel values to RGB colours. It allows the colours
of a low-depth bitmap, for example, to be mapped to the available colours in a display.
%TODO: topic overview for wxPalette.
\wxheading{Derived from}
\helpref{wxGDIObject}{wxgdiobject}\\
\helpref{wxObject}{wxobject}
\wxheading{Include files}
<wx/palette.h>
\wxheading{Predefined objects}
Objects:
{\bf wxNullPalette}
\wxheading{See also}
\helpref{wxDC::SetPalette}{wxdcsetpalette}, \helpref{wxBitmap}{wxbitmap}
\latexignore{\rtfignore{\wxheading{Members}}}
\membersection{wxPalette::wxPalette}\label{wxpalettector}
\func{}{wxPalette}{\void}
Default constructor.
\func{}{wxPalette}{\param{const wxPalette\&}{ palette}}
Copy constructor. This uses reference counting so is a cheap operation.
\func{}{wxPalette}{\param{int}{ n}, \param{const unsigned char* }{red},\\
\param{const unsigned char* }{green}, \param{const unsigned char* }{blue}}
Creates a palette from arrays of size {\it n}, one for each
red, blue or green component.
\wxheading{Parameters}
\docparam{palette}{A pointer or reference to the palette to copy.}
\docparam{n}{The number of indices in the palette.}
\docparam{red}{An array of red values.}
\docparam{green}{An array of green values.}
\docparam{blue}{An array of blue values.}
\wxheading{See also}
\helpref{wxPalette::Create}{wxpalettecreate}
\perlnote{In wxPerl the third constructor form takes as parameters
3 array references ( they must be of the same length ).}
\membersection{wxPalette::\destruct{wxPalette}}\label{wxpalettedtor}
\func{}{\destruct{wxPalette}}{\void}
Destructor.
\membersection{wxPalette::Create}\label{wxpalettecreate}
\func{bool}{Create}{\param{int}{ n}, \param{const unsigned char* }{red},\rtfsp
\param{const unsigned char* }{green}, \param{const unsigned char* }{blue}}
Creates a palette from arrays of size {\it n}, one for each
red, blue or green component.
\wxheading{Parameters}
\docparam{n}{The number of indices in the palette.}
\docparam{red}{An array of red values.}
\docparam{green}{An array of green values.}
\docparam{blue}{An array of blue values.}
\wxheading{Return value}
true if the creation was successful, false otherwise.
\wxheading{See also}
\helpref{wxPalette::wxPalette}{wxpalettector}
\membersection{wxPalette::GetPixel}\label{wxpalettegetpixel}
\constfunc{int}{GetPixel}{\param{const unsigned char }{red}, \param{const unsigned char }{green},\rtfsp
\param{const unsigned char }{blue}}
Returns a pixel value (index into the palette) for the given RGB values.
\wxheading{Parameters}
\docparam{red}{Red value.}
\docparam{green}{Green value.}
\docparam{blue}{Blue value.}
\wxheading{Return value}
The nearest palette index.
\wxheading{See also}
\helpref{wxPalette::GetRGB}{wxpalettegetrgb}
\membersection{wxPalette::GetRGB}\label{wxpalettegetrgb}
\constfunc{bool}{GetPixel}{\param{int}{ pixel}, \param{const unsigned char* }{red}, \param{const unsigned char* }{green},\rtfsp
\param{const unsigned char* }{blue}}
Returns RGB values for a given palette index.
\wxheading{Parameters}
\docparam{pixel}{The palette index.}
\docparam{red}{Receives the red value.}
\docparam{green}{Receives the green value.}
\docparam{blue}{Receives the blue value.}
\wxheading{Return value}
true if the operation was successful.
\wxheading{See also}
\helpref{wxPalette::GetPixel}{wxpalettegetpixel}
\perlnote{In wxPerl this method takes only the {\tt pixel} parameter and
returns a 3-element list ( or the empty list upon failure ).}
\membersection{wxPalette::Ok}\label{wxpaletteok}
\constfunc{bool}{Ok}{\void}
Returns true if palette data is present.
\membersection{wxPalette::operator $=$}\label{wxpaletteassignment}
\func{wxPalette\&}{operator $=$}{\param{const wxPalette\& }{palette}}
Assignment operator, using reference counting. Returns a reference
to `this'.
\membersection{wxPalette::operator $==$}\label{wxpaletteequals}
\func{bool}{operator $==$}{\param{const wxPalette\& }{palette}}
Equality operator. Two palettes are equal if they contain pointers
to the same underlying palette data. It does not compare each attribute,
so two independently-created palettes using the same parameters will
fail the test.
\membersection{wxPalette::operator $!=$}\label{wxpalettenotequals}
\func{bool}{operator $!=$}{\param{const wxPalette\& }{palette}}
Inequality operator. Two palettes are not equal if they contain pointers
to different underlying palette data. It does not compare each attribute.