bug#52231: 29.0.50; pixel-scroll-precision-mode conflicts with scroll-margin

bug#52231: 29.0.50; pixel-scroll-precision-mode conflicts with scroll-margin

[Yuan Fu]

It seems that if I set scroll-margin to, say, 4, and enable
pixel-scroll-precision-mode, the screen keeps jumping back while I
scroll down.

To reproduce, run

(progn (setq scroll-margin 4)
       (pixel-scroll-precision-mode))

And scroll down a buffer with mouse wheel.


In GNU Emacs 29.0.50 (build 1, x86_64-apple-darwin21.1.0, NS appkit-2113.00 Version 12.0.1 (Build 21A559))
of 2021-11-29 built on Brown
Repository revision: 50379fb78d04deb9f422b906add126219a1a775d
Repository branch: master
Windowing system distributor 'Apple', version 10.3.2113
System Description:  macOS 12.0.1

Configured using:
'configure --with-pdumper=yes --with-ns'

Configured features:
ACL DBUS GLIB GNUTLS JSON LCMS2 LIBXML2 MODULES NOTIFY KQUEUE NS PDUMPER
PNG RSVG THREADS TOOLKIT_SCROLL_BARS WEBP XIM ZLIB

Important settings:
  value of $LC_CTYPE: en_US.UTF-8
  locale-coding-system: utf-8-unix

Major mode: Lisp Interaction

Minor modes in effect:
  pixel-scroll-precision-mode: t
  tooltip-mode: t
  global-eldoc-mode: t
  eldoc-mode: t
  show-paren-mode: t
  electric-indent-mode: t
  mouse-wheel-mode: t
  tool-bar-mode: t
  menu-bar-mode: t
  file-name-shadow-mode: t
  global-font-lock-mode: t
  font-lock-mode: t
  blink-cursor-mode: t
  auto-composition-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t
  line-number-mode: t
  indent-tabs-mode: t
  transient-mark-mode: t

Load-path shadows:
None found.

Features:
(shadow sort mail-extr emacsbug message mailcap yank-media rmc puny
dired dired-loaddefs rfc822 mml mml-sec epa derived epg rfc6068
epg-config gnus-util rmail rmail-loaddefs auth-source cl-seq eieio
eieio-core cl-macs eieio-loaddefs password-cache json map
text-property-search seq gv byte-opt bytecomp byte-compile cconv
mm-decode mm-bodies mm-encode mail-parse rfc2231 mailabbrev gmm-utils
mailheader sendmail rfc2047 rfc2045 ietf-drums mm-util mail-prsvr
mail-utils vc-git diff-mode easy-mmode vc-dispatcher cus-start cus-load
pixel-scroll time-date subr-x cl-loaddefs cl-lib iso-transl tooltip
eldoc paren electric uniquify ediff-hook vc-hooks lisp-float-type
elisp-mode mwheel term/ns-win ns-win ucs-normalize mule-util
term/common-win tool-bar dnd fontset image regexp-opt fringe
tabulated-list replace newcomment text-mode lisp-mode prog-mode register
page tab-bar menu-bar rfn-eshadow isearch easymenu timer select
scroll-bar mouse jit-lock font-lock syntax font-core term/tty-colors
frame minibuffer cl-generic cham georgian utf-8-lang misc-lang
vietnamese tibetan thai tai-viet lao korean japanese eucjp-ms cp51932
hebrew greek romanian slovak czech european ethiopic indian cyrillic
chinese composite emoji-zwj charscript charprop case-table epa-hook
jka-cmpr-hook help simple abbrev obarray cl-preloaded nadvice button
loaddefs faces cus-face macroexp files window text-properties overlay
sha1 md5 base64 format env code-pages mule custom widget keymap
hashtable-print-readable backquote threads dbusbind kqueue cocoa ns
lcms2 multi-tty make-network-process emacs)

Memory information:
((conses 16 68311 11915)
(symbols 48 8127 1)
(strings 32 22000 2025)
(string-bytes 1 680470)
(vectors 16 14059)
(vector-slots 8 189764 11196)
(floats 8 177 333)
(intervals 56 548 1)
(buffers 992 13))

bug#52231: 29.0.50; Display property plus strike-through doesn't work

[Yuan Fu]

[-- Attachment #1: Type: text/plain, Size: 116 bytes --]

CC’ing Po Lu (is this the right way to notify someone on debbugs?)

Attached is a screencast of the symptom.


[-- Attachment #2: pixel-scroll-margin.mp4 --]
[-- Type: video/mp4, Size: 1149677 bytes --]

bug#52231: 29.0.50; Display property plus strike-through doesn't work

[Yuan Fu]

Sorry, I replied to the wrong report. 😢

Yuan

bug#52231: 29.0.50; pixel-scroll-precision-mode conflicts with scroll-margin

[Yuan Fu]

[-- Attachment #1: Type: text/plain, Size: 116 bytes --]

CC’ing Po Lu (is this the right way to notify someone on debbugs?)

Attached is a screencast of the symptom.


[-- Attachment #2: pixel-scroll-margin.mp4 --]
[-- Type: video/mp4, Size: 1149677 bytes --]

bug#52231: 29.0.50; Display property plus strike-through doesn't work

[Po Lu via Bug reports for GNU Emacs, the Swiss army knife of text editors]

Yuan Fu <casouri@gmail.com> writes:

> CC’ing Po Lu (is this the right way to notify someone on debbugs?)
>
> Attached is a screencast of the symptom.

I think you may have replied to the wrong bug.

I will look into this however, thanks.

bug#52231: 29.0.50; pixel-scroll-precision-mode conflicts with scroll-margin

[Po Lu via Bug reports for GNU Emacs, the Swiss army knife of text editors]

Po Lu <luangruo@yahoo.com> writes:

> Yuan Fu <casouri@gmail.com> writes:
>
>> CC’ing Po Lu (is this the right way to notify someone on debbugs?)
>>
>> Attached is a screencast of the symptom.
>
> I think you may have replied to the wrong bug.
>
> I will look into this however, thanks.

Please try now to see if the issue has been resolved, thanks.

bug#52231: 29.0.50; pixel-scroll-precision-mode conflicts with scroll-margin

[Juri Linkov]

> CC’ing Po Lu (is this the right way to notify someone on debbugs?)

Yes, this is the right way to notify someone while replying to the
existing debbugs report.

But CC’ing causes problems only when creating a new bug report.
For a new bug report, please see admin/notes/bugtracker:

  ** How do I report a bug?
  Use M-x report-emacs-bug, or send mail to bug-gnu-emacs@gnu.org.
  If you want to Cc someone, use an "X-Debbugs-Cc" header (or
  pseudo-header, see below) instead.

and

  iii) If you want to Cc someone, use X-Debbugs-Cc: (note this only
  applies to _new_ reports, not followups).

and

  ** How do I reply to an existing bug report?
  Reply to 123@debbugs.gnu.org, replacing 123 with the number
  of the bug you are interested in.  NB this only sends mail to the
  bug-list, it does NOT send a Cc to the original bug submitter.
  So you need to explicitly Cc him/her (and anyone else you like).
  (This works the same way as all the Emacs mailing lists.  We generally
  don't assume anyone who posts to a list is subscribed to it, so we
  cc everyone on replies.)

and

  ** When reporting a new bug, to send a Cc to another address
  (e.g. bug-cc-mode@gnu.org), do NOT just use a Cc: header.
  Instead, use "X-Debbugs-Cc:".  This ensures the Cc address(es) will get a
  mail with the bug report number in.  If you do not do this, each reply
  in the subsequent discussion might end up creating a new bug.
  This is annoying.  (So annoying that a form of message-id tracking has
  been implemented to hopefully stop this happening, but it is still
  better to use X-Debbugs-Cc.)

There is more information about this in the same file.

bug#52231: 29.0.50; pixel-scroll-precision-mode conflicts with scroll-margin

[Yuan Fu]

[-- Attachment #1: Type: text/plain, Size: 703 bytes --]

> Please try now to see if the issue has been resolved, thanks.

I tried and it now works beautifully, thanks!

However, scroll-margin seems to still mess up scrolling when there are images. You don’t even need images taller than the window height. When there are some images in the window, scrolling either doesn’t take any effect (beginning of the video), or jerks around but doesn’t scroll down (end of the video).

Admittedly this is not a pixel-scroll-precision-mode problem: Emacs without it doesn’t scroll either. I suppose it is because there are too few lines in the window (because of images) that a scroll margin of 4 breaks scrolling. Maybe I should file a separate report?


[-- Attachment #2: pixel-scroll-image.mp4 --]
[-- Type: video/mp4, Size: 404432 bytes --]

[-- Attachment #3: Type: text/plain, Size: 14 bytes --]



Thanks,
Yuan

bug#52231: 29.0.50; pixel-scroll-precision-mode conflicts with scroll-margin

[Eli Zaretskii]

> From: Yuan Fu <casouri@gmail.com>
> Date: Thu, 2 Dec 2021 11:22:49 -0800
> Cc: Po Lu <luangruo@yahoo.com>
> 
> Admittedly this is not a pixel-scroll-precision-mode problem: Emacs without it doesn’t scroll either. I suppose it is because there are too few lines in the window (because of images) that a scroll margin of 4 breaks scrolling. Maybe I should file a separate report?

You are supposed to "scroll" with C-n past such tall images.

bug#52231: 29.0.50; pixel-scroll-precision-mode conflicts with scroll-margin

[Po Lu via Bug reports for GNU Emacs, the Swiss army knife of text editors]

Yuan Fu <casouri@gmail.com> writes:

> I tried and it now works beautifully, thanks!

> However, scroll-margin seems to still mess up scrolling when there are
> images. You don’t even need images taller than the window height. When
> there are some images in the window, scrolling either doesn’t take any
> effect (beginning of the video), or jerks around but doesn’t scroll
> down (end of the video).

I don't know how to make that work.  I will look into it however, but
that's a separate bug, so I'm closing this report.

Thanks.

bug#52231: 29.0.50; pixel-scroll-precision-mode conflicts with scroll-margin

[Yuan Fu]

> On Dec 2, 2021, at 4:33 PM, Po Lu <luangruo@yahoo.com> wrote:
> 
> Yuan Fu <casouri@gmail.com> writes:
> 
>> I tried and it now works beautifully, thanks!
> 
>> However, scroll-margin seems to still mess up scrolling when there are
>> images. You don’t even need images taller than the window height. When
>> there are some images in the window, scrolling either doesn’t take any
>> effect (beginning of the video), or jerks around but doesn’t scroll
>> down (end of the video).
> 
> I don't know how to make that work.  I will look into it however, but
> that's a separate bug, so I'm closing this report.
> 
> Thanks.

I see that you are working on allowing point to be out side window. Maybe in that case (we allow point to be outside the window), scroll-margin would not take effect and this would not be a problem anymore. 

Yuan