made Convert() methods const

[wxWidgets.git] / docs / latex / wx / palette.tex

\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{wxpaletteconstr}

\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}}

\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}{wxpaletteconstr}

\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.