master 897a101: Make pixel scrolling through images at the first line smoother

[Po Lu]

branch: master
commit 897a101cd3b7d6b46e3b14e80e3c77373246be6a
Author: Po Lu <luangruo@yahoo.com>
Commit: Po Lu <luangruo@yahoo.com>

    Make pixel scrolling through images at the first line smoother
    
    * lisp/better-pixel-scroll.el (better-pixel-scroll-scroll-up):
    Try to reset vscroll if already vscrolled.
---
 lisp/better-pixel-scroll.el | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/lisp/better-pixel-scroll.el b/lisp/better-pixel-scroll.el
index 6101778..c146910 100644
--- a/lisp/better-pixel-scroll.el
+++ b/lisp/better-pixel-scroll.el
@@ -88,10 +88,11 @@ the height of the current window."
              (current-y (+ (cdr (posn-x-y posn))
                            (cdr (posn-object-width-height posn)))))
     (while (< (- max-y current-y) delta)
-      (when (zerop (vertical-motion -1))
-       (set-window-vscroll nil 0)
-       (signal 'beginning-of-buffer nil))
+      (vertical-motion -1)
       (setq current-y (- current-y (line-pixel-height)))))
+  (let ((current-vscroll (window-vscroll nil t)))
+    (setq delta (- delta current-vscroll))
+    (set-window-vscroll nil 0 t))
   (while (> delta 0)
     (set-window-start nil (save-excursion
                             (goto-char (window-start))