(frame-set-background-mode):

  Only do anything if the bg-mode or display-type has actually changed.
  Use `dolist'.

2 files changed, 43 insertions, 38 deletions

diff --git a/lisp/ChangeLog b/lisp/ChangeLog
index a8f2cad62ca..d23eac19c8b 100644
--- a/lisp/ChangeLog
+++ b/lisp/ChangeLog
@@ -1,7 +1,8 @@
-2000-10-11  Miles Bader  <miles@lsi.nec.co.jp>
+2000-10-11  Miles Bader  <miles@gnu.org>
 
         * faces.el (frame-set-background-mode): Pay attention to saved
-        face specs as well as default ones.
+        face specs as well as default ones.  Only do anything if the
+        bg-mode or display-type has actually changed.  Use `dolist'.
 
 2000-10-10  Sam Steingold  <sds@gnu.org>
 
diff --git a/lisp/faces.el b/lisp/faces.el
index 6906c05447f..c847d9f71a7 100644
--- a/lisp/faces.el
+++ b/lisp/faces.el
@@ -1308,42 +1308,46 @@ this won't have the expected effect."
   (let* ((bg-resource
           (and window-system
                (x-get-resource ".backgroundMode" "BackgroundMode")))
-         (bg-mode (cond (frame-background-mode)
-                        ((null window-system)
-                         ;; No way to determine this automatically (?).
-                         'dark)
-                        (bg-resource
-                         (intern (downcase bg-resource)))
-                        ((< (apply '+ (x-color-values
-                                       (frame-parameter frame 'background-color)
-                                       frame))
-                            ;; Just looking at the screen, colors whose
-                            ;; values add up to .6 of the white total
-                            ;; still look dark to me.
-                            (* (apply '+ (x-color-values "white" frame)) .6))
-                         'dark)
-                        (t 'light)))
-         (display-type (cond ((null window-system)
-                              (if (tty-display-color-p frame) 'color 'mono))
-                             ((x-display-color-p frame)
-                              'color)
-                             ((x-display-grayscale-p frame)
-                              'grayscale)
-                             (t 'mono))))
-    (modify-frame-parameters frame
-                             (list (cons 'background-mode bg-mode)
-                                   (cons 'display-type display-type))))
-  
-  ;; For all named faces, choose face specs matching the new frame
-  ;; parameters.
-  (let ((face-list (face-list)))
-    (while face-list
-      (let* ((face (car face-list))
-             (spec (or (get face 'saved-face)
-                       (get face 'face-defface-spec))))
-        (when spec
-          (face-spec-set face spec frame))
-      (setq face-list (cdr face-list))))))
+         (bg-mode
+          (cond (frame-background-mode)
+                ((null window-system)
+                 ;; No way to determine this automatically (?).
+                 'dark)
+                (bg-resource
+                 (intern (downcase bg-resource)))
+                ((< (apply '+ (x-color-values
+                               (frame-parameter frame 'background-color)
+                               frame))
+                    ;; Just looking at the screen, colors whose
+                    ;; values add up to .6 of the white total
+                    ;; still look dark to me.
+                    (* (apply '+ (x-color-values "white" frame)) .6))
+                 'dark)
+                (t 'light)))
+         (display-type
+          (cond ((null window-system)
+                 (if (tty-display-color-p frame) 'color 'mono))
+                ((x-display-color-p frame)
+                 'color)
+                ((x-display-grayscale-p frame)
+                 'grayscale)
+                (t 'mono)))
+         (old-bg-mode
+          (frame-parameter frame 'background-mode))
+         (old-display-type
+          (frame-parameter frame 'display-type)))
+
+    (unless (and (eq bg-mode old-bg-mode) (eq display-type old-display-type))
+      (modify-frame-parameters frame
+                               (list (cons 'background-mode bg-mode)
+                                     (cons 'display-type display-type)))
+      ;; For all named faces, choose face specs matching the new frame
+      ;; parameters.
+      (dolist (face (face-list))
+        (let ((spec (or (get face 'saved-face)
+                        (get face 'face-defface-spec))))
+          (when spec
+            (face-spec-set face spec frame)))))))