From 6ae315b0d873be00a8d630aebd922b11244d40b8 Mon Sep 17 00:00:00 2001 From: Miles Bader Date: Sun, 9 Jun 2002 12:57:35 +0000 Subject: [PATCH] (display-supports-face-attributes-p): New function. --- lisp/faces.el | 24 ++++++++++++++++++++++++ 1 file changed, 24 insertions(+) diff --git a/lisp/faces.el b/lisp/faces.el index ea391ae6149..83832f2b47f 100644 --- a/lisp/faces.el +++ b/lisp/faces.el @@ -1477,6 +1477,30 @@ If omitted or nil, that stands for the selected frame's display." (t (> (tty-color-gray-shades display) 2))))) +(defun display-supports-face-attributes-p (attributes &optional display) + "Return non-nil if all the face attributes in ATTRIBUTES are supported. +The optional argument DISPLAY can be a display name, a frame, or +nil (meaning the selected frame's display) + +The definition of `supported' is somewhat heuristic, but basically means +that a face containing all the attributes in ATTRIBUTES, when merged +with the default face for display, can be represented in a way that's + + (1) different in appearance than the default face, and + (2) `close in spirit' to what the attributes specify, if not exact. + +Point (2) implies that a `:weight black' attribute will be satisified by +any display that can display bold, and a `:foreground \"yellow\"' as long +as it can display a yellowish color, but `:slant italic' will _not_ be +satisified by the tty display code's automatic substitution of a `dim' +face for italic." + (let ((frame (car (frames-on-display-list display)))) + ;; For now, we assume that non-tty displays can support everything. + ;; Later, we should add the ability to query about specific fonts, + ;; colors, etc. + (or (memq (framep frame) '(x w32 mac)) + (tty-supports-face-attributes-p attributes frame)))) + ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ;;; Background mode. -- 2.39.2