docs/latex/wx/palette.tex

   1 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
   2 %% Name:        palette.tex
   3 %% Purpose:     wxPalette docs
   4 %% Author:
   5 %% Modified by:
   6 %% Created:
   7 %% RCS-ID:      $Id$
   8 %% Copyright:   (c) wxWidgets
   9 %% License:     wxWindows license
  10 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  11
  12 \section{\class{wxPalette}}\label{wxpalette}
  13
  14 A palette is a table that maps pixel values to RGB colours. It allows the
  15 colours of a low-depth bitmap, for example, to be mapped to the available
  16 colours in a display. The notion of palettes is becoming more and more
  17 obsolete nowadays and only the MSW port is still using a native palette.
  18 All other ports use generic code which is basically just an array of
  19 colours.
  20
  21 It is likely that in the future the only use for palettes within wxWidgets
  22 will be for representing colour indeces from images (such as GIF or PNG).
  23 The image handlers for these formats have been modified to create a palette
  24 if there is such information in the original image file (usually 256 or less
  25 colour images). See \helpref{wxImage}{wximage} for more information.
  26
  27 %TODO: topic overview for wxPalette.
  28 \wxheading{Derived from}
  29
  30 \helpref{wxGDIObject}{wxgdiobject}\\
  31 \helpref{wxObject}{wxobject}
  32
  33 \wxheading{Include files}
  34
  35 <wx/palette.h>
  36
  37 \wxheading{Library}
  38
  39 \helpref{wxCore}{librarieslist}
  40
  41 \wxheading{Predefined objects}
  42
  43 Objects:
  44
  45 {\bf wxNullPalette}
  46
  47 \wxheading{See also}
  48
  49 \helpref{wxDC::SetPalette}{wxdcsetpalette}, \helpref{wxBitmap}{wxbitmap}
  50
  51 \latexignore{\rtfignore{\wxheading{Members}}}
  52
  53 \membersection{wxPalette::wxPalette}\label{wxpalettector}
  54
  55 \func{}{wxPalette}{\void}
  56
  57 Default constructor.
  58
  59 \func{}{wxPalette}{\param{const wxPalette\&}{ palette}}
  60
  61 Copy constructor, uses \helpref{reference counting}{trefcount}.
  62
  63 \func{}{wxPalette}{\param{int}{ n}, \param{const unsigned char* }{red},\\
  64  \param{const unsigned char* }{green}, \param{const unsigned char* }{blue}}
  65
  66 Creates a palette from arrays of size {\it n}, one for each
  67 red, blue or green component.
  68
  69 \wxheading{Parameters}
  70
  71 \docparam{palette}{A pointer or reference to the palette to copy.}
  72
  73 \docparam{n}{The number of indices in the palette.}
  74
  75 \docparam{red}{An array of red values.}
  76
  77 \docparam{green}{An array of green values.}
  78
  79 \docparam{blue}{An array of blue values.}
  80
  81 \wxheading{See also}
  82
  83 \helpref{wxPalette::Create}{wxpalettecreate}
  84
  85 \perlnote{In wxPerl the third constructor form takes as parameters
  86   3 array references ( they must be of the same length ).}
  87
  88 \membersection{wxPalette::\destruct{wxPalette}}\label{wxpalettedtor}
  89
  90 \func{}{\destruct{wxPalette}}{\void}
  91
  92 Destructor.
  93 See \helpref{reference-counted object destruction}{refcountdestruct} for more info.
  94
  95 \membersection{wxPalette::Create}\label{wxpalettecreate}
  96
  97 \func{bool}{Create}{\param{int}{ n}, \param{const unsigned char* }{red},\rtfsp
  98  \param{const unsigned char* }{green}, \param{const unsigned char* }{blue}}
  99
 100 Creates a palette from arrays of size {\it n}, one for each
 101 red, blue or green component.
 102
 103 \wxheading{Parameters}
 104
 105 \docparam{n}{The number of indices in the palette.}
 106
 107 \docparam{red}{An array of red values.}
 108
 109 \docparam{green}{An array of green values.}
 110
 111 \docparam{blue}{An array of blue values.}
 112
 113 \wxheading{Return value}
 114
 115 true if the creation was successful, false otherwise.
 116
 117 \wxheading{See also}
 118
 119 \helpref{wxPalette::wxPalette}{wxpalettector}
 120
 121 \membersection{wxPalette::GetColoursCount}\label{wxpalettegetcolourscount}
 122
 123 \constfunc{int}{GetColoursCount}{\void}
 124
 125 Returns number of entries in palette.
 126
 127 \membersection{wxPalette::GetPixel}\label{wxpalettegetpixel}
 128
 129 \constfunc{int}{GetPixel}{\param{unsigned char }{red}, \param{unsigned char }{green},\rtfsp
 130  \param{unsigned char }{blue}}
 131
 132 Returns a pixel value (index into the palette) for the given RGB values.
 133
 134 \wxheading{Parameters}
 135
 136 \docparam{red}{Red value.}
 137
 138 \docparam{green}{Green value.}
 139
 140 \docparam{blue}{Blue value.}
 141
 142 \wxheading{Return value}
 143
 144 The nearest palette index or {\tt wxNOT\_FOUND} for unexpected errors.
 145
 146 \wxheading{See also}
 147
 148 \helpref{wxPalette::GetRGB}{wxpalettegetrgb}
 149
 150 \membersection{wxPalette::GetRGB}\label{wxpalettegetrgb}
 151
 152 \constfunc{bool}{GetRGB}{\param{int}{ pixel}, \param{const unsigned char* }{red}, \param{const unsigned char* }{green},\rtfsp
 153  \param{const unsigned char* }{blue}}
 154
 155 Returns RGB values for a given palette index.
 156
 157 \wxheading{Parameters}
 158
 159 \docparam{pixel}{The palette index.}
 160
 161 \docparam{red}{Receives the red value.}
 162
 163 \docparam{green}{Receives the green value.}
 164
 165 \docparam{blue}{Receives the blue value.}
 166
 167 \wxheading{Return value}
 168
 169 true if the operation was successful.
 170
 171 \wxheading{See also}
 172
 173 \helpref{wxPalette::GetPixel}{wxpalettegetpixel}
 174
 175 \perlnote{In wxPerl this method takes only the {\tt pixel} parameter and
 176   returns a 3-element list ( or the empty list upon failure ).}
 177
 178 \membersection{wxPalette::IsOk}\label{wxpaletteisok}
 179
 180 \constfunc{bool}{IsOk}{\void}
 181
 182 Returns true if palette data is present.
 183
 184 \membersection{wxPalette::operator $=$}\label{wxpaletteassignment}
 185
 186 \func{wxPalette\&}{operator $=$}{\param{const wxPalette\& }{palette}}
 187
 188 Assignment operator, using \helpref{reference counting}{trefcount}.
 189