Special Text Highlighting Techniques

Although EPIC is a text-based irc client, it still has many ways of marking
text such that it stands out from the rest.  The simplest kinds of text
highlighting are boldface, underline, and reverse video.  They work simply
by surrounding the desired text with the appropriate control characters:

   Char   Input   Description                                               
    ^B      B     toggles boldfacing on/off
    ^V      V     toggles reverse video on/off
    ^_      _     toggles underlining on/off
    ^O      O     turns off all highlighting

The "char" is the character typed to achieve the desired effect; ^B means
control-b, etc.  The "input" is how the character appears if typed on the
input line.  The settings BOLD_VIDEO, INVERSE_VIDEO, and UNDERLINE_VIDEO
govern whether they will actually be displayed in the display window.  In
truth, other keys may be bound to the highlighting characters, but they will
always be displayed as shown above.

In addition, EPIC also supports the use of ANSI escape sequences inside the
display window (ircII itself does not).  The main use for this is for using
color.  ANSI escape sequences are really much more powerful than that, but
a full discussion is beyond the scope of this document.  We will focus on
how to use them to colorize text output.

EPIC controls whether escape sequences are passed to the display window with
the DISPLAY_ANSI setting.  It is off by default.  All of the above effects
can be achieved with escape sequences as well.  For text highlighting, all
sequences have the following form (E is the ESC character):

   E[#m

The '#' is some number.  Multiple effects can be set at once (assuming they
don't clash with each other) with either of these forms:

   E[#mE[#m
   E[#;#m

For the purposes of this discussion, the following numbers may be used:

   Code   Effect                     | Code    Text/Background Color  
     0    turn off all highlighting  | 30/40   black
     1    turn bold on               | 31/41   red
     2    turn bold off              | 32/42   green
     3    turn underline on          | 33/43   yellow
     5    turn blink on              | 34/44   blue
     7    turn reverse video on      | 35/45   magenta (purple)
                                     | 36/46   cyan (aqua)
                                     | 37/47   white

For example, the first word in the following text would be red:

   E[31m***E[0m Alert! Alert!

See Also:
   bind(4) bold, highlight_off, reverse, underline; set(4) bold_video,
   display_ansi, inverse_video, underline_video