docs/latex/wx/palette.tex

   1 \section{\class{wxPalette}}\label{wxpalette}
   2
   3 A palette is a table that maps pixel values to RGB colours. It allows the colours
   4 of a low-depth bitmap, for example, to be mapped to the available colours in a display.
   5
   6 %TODO: topic overview for wxPalette.
   7 \wxheading{Derived from}
   8
   9 \helpref{wxGDIObject}{wxgdiobject}\\
  10 \helpref{wxObject}{wxobject}
  11
  12 \wxheading{Include files}
  13
  14 <wx/palette.h>
  15
  16 \wxheading{Predefined objects}
  17
  18 Objects:
  19
  20 {\bf wxNullPalette}
  21
  22 \wxheading{See also}
  23
  24 \helpref{wxDC::SetPalette}{wxdcsetpalette}, \helpref{wxBitmap}{wxbitmap}
  25
  26 \latexignore{\rtfignore{\wxheading{Members}}}
  27
  28 \membersection{wxPalette::wxPalette}\label{wxpaletteconstr}
  29
  30 \func{}{wxPalette}{\void}
  31
  32 Default constructor.
  33
  34 \func{}{wxPalette}{\param{const wxPalette\&}{ palette}}
  35
  36 Copy constructor. This uses reference counting so is a cheap operation.
  37
  38 \func{}{wxPalette}{\param{int}{ n}, \param{const unsigned char* }{red},\\
  39  \param{const unsigned char* }{green}, \param{const unsigned char* }{blue}}
  40
  41 Creates a palette from arrays of size {\it n}, one for each
  42 red, blue or green component.
  43
  44 \wxheading{Parameters}
  45
  46 \docparam{palette}{A pointer or reference to the palette to copy.}
  47
  48 \docparam{n}{The number of indices in the palette.}
  49
  50 \docparam{red}{An array of red values.}
  51
  52 \docparam{green}{An array of green values.}
  53
  54 \docparam{blue}{An array of blue values.}
  55
  56 \wxheading{See also}
  57
  58 \helpref{wxPalette::Create}{wxpalettecreate}
  59
  60 \perlnote{In wxPerl the third constructor form takes as parameters
  61   3 array references ( they must be of the same length ).}
  62
  63 \membersection{wxPalette::\destruct{wxPalette}}
  64
  65 \func{}{\destruct{wxPalette}}{\void}
  66
  67 Destructor.
  68
  69 \membersection{wxPalette::Create}\label{wxpalettecreate}
  70
  71 \func{bool}{Create}{\param{int}{ n}, \param{const unsigned char* }{red},\rtfsp
  72  \param{const unsigned char* }{green}, \param{const unsigned char* }{blue}}
  73
  74 Creates a palette from arrays of size {\it n}, one for each
  75 red, blue or green component.
  76
  77 \wxheading{Parameters}
  78
  79 \docparam{n}{The number of indices in the palette.}
  80
  81 \docparam{red}{An array of red values.}
  82
  83 \docparam{green}{An array of green values.}
  84
  85 \docparam{blue}{An array of blue values.}
  86
  87 \wxheading{Return value}
  88
  89 true if the creation was successful, false otherwise.
  90
  91 \wxheading{See also}
  92
  93 \helpref{wxPalette::wxPalette}{wxpaletteconstr}
  94
  95 \membersection{wxPalette::GetPixel}\label{wxpalettegetpixel}
  96
  97 \constfunc{int}{GetPixel}{\param{const unsigned char }{red}, \param{const unsigned char }{green},\rtfsp
  98  \param{const unsigned char }{blue}}
  99
 100 Returns a pixel value (index into the palette) for the given RGB values.
 101
 102 \wxheading{Parameters}
 103
 104 \docparam{red}{Red value.}
 105
 106 \docparam{green}{Green value.}
 107
 108 \docparam{blue}{Blue value.}
 109
 110 \wxheading{Return value}
 111
 112 The nearest palette index.
 113
 114 \wxheading{See also}
 115
 116 \helpref{wxPalette::GetRGB}{wxpalettegetrgb}
 117
 118 \membersection{wxPalette::GetRGB}\label{wxpalettegetrgb}
 119
 120 \constfunc{bool}{GetPixel}{\param{int}{ pixel}, \param{const unsigned char* }{red}, \param{const unsigned char* }{green},\rtfsp
 121  \param{const unsigned char* }{blue}}
 122
 123 Returns RGB values for a given palette index.
 124
 125 \wxheading{Parameters}
 126
 127 \docparam{pixel}{The palette index.}
 128
 129 \docparam{red}{Receives the red value.}
 130
 131 \docparam{green}{Receives the green value.}
 132
 133 \docparam{blue}{Receives the blue value.}
 134
 135 \wxheading{Return value}
 136
 137 true if the operation was successful.
 138
 139 \wxheading{See also}
 140
 141 \helpref{wxPalette::GetPixel}{wxpalettegetpixel}
 142
 143 \perlnote{In wxPerl this method takes only the {\tt pixel} parameter and
 144   returns a 3-element list ( or the empty list upon failure ).}
 145
 146 \membersection{wxPalette::Ok}\label{wxpaletteok}
 147
 148 \constfunc{bool}{Ok}{\void}
 149
 150 Returns true if palette data is present.
 151
 152 \membersection{wxPalette::operator $=$}\label{wxpaletteassignment}
 153
 154 \func{wxPalette\&}{operator $=$}{\param{const wxPalette\& }{palette}}
 155
 156 Assignment operator, using reference counting. Returns a reference
 157 to `this'.
 158
 159 \membersection{wxPalette::operator $==$}\label{wxpaletteequals}
 160
 161 \func{bool}{operator $==$}{\param{const wxPalette\& }{palette}}
 162
 163 Equality operator. Two palettes are equal if they contain pointers
 164 to the same underlying palette data. It does not compare each attribute,
 165 so two independently-created palettes using the same parameters will
 166 fail the test.
 167
 168 \membersection{wxPalette::operator $!=$}\label{wxpalettenotequals}
 169
 170 \func{bool}{operator $!=$}{\param{const wxPalette\& }{palette}}
 171
 172 Inequality operator. Two palettes are not equal if they contain pointers
 173 to different underlying palette data. It does not compare each attribute.
 174
 175