Function: tty-color-gray-shades
tty-color-gray-shades is a byte-compiled function defined in
tty-colors.el.gz.
Signature
(tty-color-gray-shades &optional DISPLAY)
Documentation
Return the number of gray colors supported by DISPLAY's terminal.
A color is considered gray if the 3 components of its RGB value are equal.
Source Code
;; Defined in /usr/src/emacs/lisp/term/tty-colors.el.gz
(defun tty-color-gray-shades (&optional display)
"Return the number of gray colors supported by DISPLAY's terminal.
A color is considered gray if the 3 components of its RGB value are equal."
(let* ((frame (if (framep display) display
;; FIXME: this uses an arbitrary frame from DISPLAY!
(car (frames-on-display-list display))))
(colors (tty-color-alist frame))
(count 0)
desc r g b)
(while colors
(setq desc (cddr (car colors))
r (car desc)
g (cadr desc)
b (car (cddr desc)))
(and (numberp r)
(eq r g) (eq g b)
(setq count (1+ count)))
(setq colors (cdr colors)))
count))