On FRI, 8 DEC 2006, Johan Bockgård wrote:

> Leo <sdl.web@gmail.com> writes:
>
>> I don't quite understand how people find the glyphs.
>>
>> (dolist (c '((?\207 . ?q) (?\216 . ?x) (?\212 . ?t) (?\203 . ?m)))
>>   (aset standard-display-table (car c)
>> 	(vector (create-glyph (concat "\e(0" "\e[35m" ; magenta
>> 				      (char-to-string (cdr c))
>> 				      "\e[0m" "\e(B")))))
>
> "ESC ( C" switches character sets.
> "ESC [ N m" selects color.
>
>     http://www.xfree86.org/current/ctlseqs.html
>
> "m" is a lower-left corner character etc.
>
>     http://vt100.net/docs/tp83/appendixa.html (bottom)
>
> The \nnn numbers are somewhat arbitrary in this context.

Thank you.

Now I pick up some pieces of code from the emacswiki and put them in a
function as:

(defun my-gnus-summary-line-format-ascii-fancy ()
  "Use fancy ASCII graphics to display thread tree."
  (interactive)
  (setq gnus-summary-line-format
	(concat
	 "%0{%U%R%z%u&@;%}"
	 "%10{|%}"
	 "%1{%d%}"
	 "%10{|%}"
	 "%( %-15,15f %)"
	 "%10{|%}"
	 "%4k"
	 "%10{|%}"
	 "%2u&score;"
	 "%10{|%}"
	 "%u&thread;%s\n"))
  (unless standard-display-table
    (setq standard-display-table (make-display-table)))
  (dolist (c '((?\207 . ?q) (?\216 . ?x) (?\212 . ?t) (?\203 . ?m)))
    (aset standard-display-table (car c)
	  (vector (create-glyph (concat "\e(0" "\e[36m" ; magenta
					(char-to-string (cdr c))
					"\e[0m" "\e(B")))))
  (setq gnus-sum-thread-tree-vertical "\216"
	gnus-sum-thread-tree-root ""
	gnus-sum-thread-tree-false-root ""
	gnus-sum-thread-tree-indent " "
	gnus-sum-thread-tree-single-indent ""
	gnus-sum-thread-tree-leaf-with-other "\212\207>"
	gnus-sum-thread-tree-single-leaf "\203\207>")
  (gnus-message 5 "Using fancy ascii tree layout."))

The thread tree can be displayed in emacs starting in gnome-terminal
or xterm etc. but with strange background color. See the screen shot.