Merge pull request #16 from tsdh/master

[gnu-emacs-elpa] / beacon.el

diff --git a/beacon.el b/beacon.el
index afbe1440f56e0d11d6b38b2489bcb5a925bdf783..138c3baae401ceb7b308d52a4d9da6c9990dc65c 100644 (file)
--- a/beacon.el
+++ b/beacon.el
@@ -46,7 +46,7 @@
 
 (defvar beacon--timer nil)
 
-(defcustom beacon-push-mark nil
+(defcustom beacon-push-mark 35
   "Should the mark be pushed before long movements?
 If nil, `beacon' will not push the mark.
 Otherwise this should be a number, and `beacon' will push the
@@ -96,7 +96,7 @@ If it is a string, it is a color name or specification,
 e.g. \"#666600\"."
   :type '(choice number color))
 
-(defcustom beacon-dont-blink-predicates nil
+(defvar beacon-dont-blink-predicates nil
   "A list of predicates that prevent the beacon blink.
 These predicate functions are called in order, with no
 arguments, before blinking the beacon.  If any returns
@@ -105,9 +105,8 @@ non-nil, the beacon will not blink.
 For instance, if you want to disable beacon on buffers where
 `hl-line-mode' is on, you can do:
 
-    (add-hook 'beacon-dont-blink-predicates
-              (lambda () (bound-and-true-p hl-line-mode)))"
-  :type 'hook)
+    (add-hook \\='beacon-dont-blink-predicates
+              (lambda () (bound-and-true-p hl-line-mode)))")
 
 (add-hook 'beacon-dont-blink-predicates #'window-minibuffer-p)
 
@@ -265,6 +264,11 @@ Only returns `beacon-size' elements."
 (defvar beacon--previous-mark-head nil)
 (defvar beacon--previous-window nil)
 
+(defun beacon--pos-on-current-line-p (pos)
+  "Return non-nil if POS is on the current line."
+  (and (<= (save-excursion (beginning-of-line) (point)) pos)
+       (<= pos (save-excursion (end-of-line) (point)))))
+
 (defun beacon--movement-> (delta)
   "Return non-nil if latest point movement is > DELTA.
 If DELTA is nil, return nil."
@@ -274,9 +278,21 @@ If DELTA is nil, return nil."
               (current-buffer))
        (> (abs (- (point) beacon--previous-place))
           delta)
-       (> (count-screen-lines (min (point) beacon--previous-place)
-                              (max (point) beacon--previous-place))
-          delta)))
+       ;; Check if the movement was larger than DELTA lines by testing if
+       ;; `point' is still on the same line or on any line DELTA lines up or
+       ;; down.  This is much cheaper than computing the actual number of lines
+       ;; moved using `count-screen-lines'.
+       (let ((prev-pos (marker-position beacon--previous-place)))
+        (catch 'movement
+          (when (beacon--pos-on-current-line-p prev-pos)
+            (throw 'movement nil))
+          (dolist (inc '(1 -1))
+            (save-excursion
+              (dotimes (i delta)
+                (vertical-motion inc)
+                (when (beacon--pos-on-current-line-p prev-pos)
+                  (throw 'movement nil)))))
+          (throw 'movement t)))))
 
 (defun beacon--maybe-push-mark ()
   "Push mark if it seems to be safe."