[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
[Emacs-diffs] emacs-26 1dfc275: Make pixel-wise scrolling less laggy
From: |
Eli Zaretskii |
Subject: |
[Emacs-diffs] emacs-26 1dfc275: Make pixel-wise scrolling less laggy |
Date: |
Sun, 7 Jan 2018 02:18:51 -0500 (EST) |
branch: emacs-26
commit 1dfc27576afe558da781b2d5f4845ca242dce3cc
Author: Tak Kunihiro <address@hidden>
Commit: Eli Zaretskii <address@hidden>
Make pixel-wise scrolling less laggy
* lisp/pixel-scroll.el (pixel-dead-time, pixel-last-scroll-time):
New variables.
(pixel-scroll-up, pixel-scroll-down): Invoke 'scroll-up' or
'scroll-down' when called within 'pixel-dead-time'. (Bug#29737)
---
lisp/pixel-scroll.el | 71 +++++++++++++++++++++++++++++++++++-----------------
1 file changed, 48 insertions(+), 23 deletions(-)
diff --git a/lisp/pixel-scroll.el b/lisp/pixel-scroll.el
index bfc48ba..d362419 100644
--- a/lisp/pixel-scroll.el
+++ b/lisp/pixel-scroll.el
@@ -82,6 +82,27 @@ case you need scrolling resolution of a pixel, set to 1.
After a
pixel scroll, typing \\[next-line] or \\[previous-line] scrolls the window to
make it
fully visible, and undoes the effect of the pixel-level scroll.")
+(defvar pixel-dead-time 0.1
+ "Minimal interval in seconds before next smooth scrolling.
+If another scrolling request arrives within this period, scrolling
+will be carried out without pixel resolution. If zero, scrolling
+is always with pixel resolution.")
+
+(defvar pixel-last-scroll-time 0
+ "Time when the last scrolling was made, in second since the epoch.")
+
+(defun pixel-scroll-in-rush-p ()
+ "Return non-nil if next scroll should be non-smooth.
+When scrolling request is delivered soon after the previous one,
+user is in hurry. When the time since last scroll is larger than
+`pixel-dead-time', we are ready for another smooth scroll, and this
+function returns nil."
+ (let* ((current-time (float-time))
+ (scroll-in-rush-p (< (- current-time pixel-last-scroll-time)
+ pixel-dead-time)))
+ (setq pixel-last-scroll-time current-time)
+ scroll-in-rush-p))
+
;;;###autoload
(define-minor-mode pixel-scroll-mode
"A minor mode to scroll text pixel-by-pixel.
@@ -104,35 +125,39 @@ if ARG is omitted or nil."
This is an alternative of `scroll-up'. Scope moves downward."
(interactive)
(or arg (setq arg 1))
- (dotimes (ii arg) ; move scope downward
- (let ((amt (if pixel-resolution-fine-flag
- (if (integerp pixel-resolution-fine-flag)
- pixel-resolution-fine-flag
- (frame-char-height))
- (pixel-line-height))))
- (if (pixel-eob-at-top-p) ; when end-of-the-buffer is close
- (scroll-up 1) ; relay on robust method
- (while (pixel-point-at-top-p amt) ; prevent too late (multi tries)
- (vertical-motion 1)) ; move point downward
- (pixel-scroll-pixel-up amt))))) ; move scope downward
+ (if (pixel-scroll-in-rush-p)
+ (scroll-up arg)
+ (dotimes (ii arg) ; move scope downward
+ (let ((amt (if pixel-resolution-fine-flag
+ (if (integerp pixel-resolution-fine-flag)
+ pixel-resolution-fine-flag
+ (frame-char-height))
+ (pixel-line-height))))
+ (if (pixel-eob-at-top-p) ; when end-of-the-buffer is close
+ (scroll-up 1) ; relay on robust method
+ (while (pixel-point-at-top-p amt) ; prevent too late (multi tries)
+ (vertical-motion 1)) ; move point downward
+ (pixel-scroll-pixel-up amt)))))) ; move scope downward
(defun pixel-scroll-down (&optional arg)
"Scroll text of selected window down ARG lines.
This is and alternative of `scroll-down'. Scope moves upward."
(interactive)
(or arg (setq arg 1))
- (dotimes (ii arg)
- (let ((amt (if pixel-resolution-fine-flag
- (if (integerp pixel-resolution-fine-flag)
- pixel-resolution-fine-flag
- (frame-char-height))
- (pixel-line-height -1))))
- (while (pixel-point-at-bottom-p amt) ; prevent too late (multi tries)
- (vertical-motion -1)) ; move point upward
- (if (or (pixel-bob-at-top-p amt) ; when beginning-of-the-buffer is
seen
- (pixel-eob-at-top-p)) ; for file with a long line
- (scroll-down 1) ; relay on robust method
- (pixel-scroll-pixel-down amt)))))
+ (if (pixel-scroll-in-rush-p)
+ (scroll-down arg)
+ (dotimes (ii arg)
+ (let ((amt (if pixel-resolution-fine-flag
+ (if (integerp pixel-resolution-fine-flag)
+ pixel-resolution-fine-flag
+ (frame-char-height))
+ (pixel-line-height -1))))
+ (while (pixel-point-at-bottom-p amt) ; prevent too late (multi tries)
+ (vertical-motion -1)) ; move point upward
+ (if (or (pixel-bob-at-top-p amt) ; when beginning-of-the-buffer is seen
+ (pixel-eob-at-top-p)) ; for file with a long line
+ (scroll-down 1) ; relay on robust method
+ (pixel-scroll-pixel-down amt))))))
(defun pixel-bob-at-top-p (amt)
"Return non-nil if window-start is at beginning of the current buffer.
[Prev in Thread] |
Current Thread |
[Next in Thread] |
- [Emacs-diffs] emacs-26 1dfc275: Make pixel-wise scrolling less laggy,
Eli Zaretskii <=