Info Catalog groff: Suppressing output groff: gtroff Reference groff: I/O

groff: Colors

 
 5.28 Colors
 ===========
 
  -- Request: .color [n]
  -- Register: \n[.color]
      If N is missing or non-zero, activate colors (this is the default);
      otherwise, turn it off.
 
      The read-only number register '.color' is 1 if colors are active,
      0 otherwise.
 
      Internally, 'color' sets a global flag; it does not produce a
      token.  Similar to the 'cp' request, you should use it at the
      beginning of your document to control color output.
 
      Colors can be also turned off with the '-c' command-line option.
 
  -- Request: .defcolor ident scheme color_components
      Define color with name IDENT.  SCHEME can be one of the following
      values: 'rgb' (three components), 'cmy' (three components), 'cmyk'
      (four components), and 'gray' or 'grey' (one component).
 
      Color components can be given either as a hexadecimal string or as
      positive decimal integers in the range 0-65535.  A hexadecimal
      string contains all color components concatenated.  It must start
      with either '#' or '##'; the former specifies hex values in the
      range 0-255 (which are internally multiplied by 257), the latter in
      the range 0-65535.  Examples: '#FFC0CB' (pink), '##ffff0000ffff'
      (magenta).  The default color name value is device-specific
      (usually black).  It is possible that the default color for '\m'
      and '\M' is not identical.
 
      A new scaling indicator 'f' has been introduced, which multiplies
      its value by 65536; this makes it convenient to specify color
      components as fractions in the range 0 to 1 (1f equals 65536u).
      Example:
 
           .defcolor darkgreen rgb 0.1f 0.5f 0.2f
 
      Note that 'f' is the default scaling indicator for the 'defcolor'
      request, thus the above statement is equivalent to
 
           .defcolor darkgreen rgb 0.1 0.5 0.2
 
  -- Request: .gcolor [color]
  -- Escape: \mc
  -- Escape: \m(co
  -- Escape: \m[color]
  -- Register: \n[.m]
      Set (glyph) drawing color.  The following examples show how to turn
      the next four words red.
 
           .gcolor red
           these are in red
           .gcolor
           and these words are in black.
 
           \m[red]these are in red\m[] and these words are in black.
 
      The escape '\m[]' returns to the previous color, as does a call to
      'gcolor' without an argument.
 
      The name of the current drawing color is available in the
      read-only, string-valued number register '.m'.
 
      The drawing color is associated with the current environment (⇒
      Environments).
 
      Note that '\m' doesn't produce an input token in 'gtroff'.  As a
      consequence, it can be used in requests like 'mc' (which expects a
      single character as an argument) to change the color on the fly:
 
           .mc \m[red]x\m[]
 
  -- Request: .fcolor [color]
  -- Escape: \Mc
  -- Escape: \M(co
  -- Escape: \M[color]
  -- Register: \n[.M]
      Set fill (background) color for filled objects drawn with the
      '\D'...'' commands.
 
      A red ellipse can be created with the following code:
 
           \M[red]\h'0.5i'\D'E 2i 1i'\M[]
 
      The escape '\M[]' returns to the previous fill color, as does a
      call to 'fcolor' without an argument.
 
      The name of the current fill (background) color is available in the
      read-only, string-valued number register '.M'.
 
      The fill color is associated with the current environment (⇒
      Environments).
 
      Note that '\M' doesn't produce an input token in 'gtroff'.
 

Info Catalog groff: Suppressing output groff: gtroff Reference groff: I/O