bug#42304: 27.0.50; Emacs does not adjust to global font scaling anymore

bug#42304: 27.0.50; Emacs does not adjust to global font scaling anymore

[Torsten Bronger]

If I re-scale all fonts on my Gnome desktop with e.g.

dconf write /org/gnome/desktop/interface/text-scaling-factor 2.0

Emacs is the only application that does not change its font size
accordingly.  Instead, I have to re-start Emacs.  This used to work
properly.  The problem was introduced with commit f208d5ae77.





In GNU Emacs 27.0.50 (build 1, x86_64-pc-linux-gnu)
 of 2020-07-10 built on brad
Repository revision: 3f9d96e3d70e94768add7d89ffcb94be7de4597e
Repository branch: HEAD
Windowing system distributor 'The X.Org Foundation', version 11.0.12008000
System Description: Ubuntu 20.04 LTS

Recent messages:
Mark set
Mark activated
Quit [2 times]
Mark set
Mark activated
Saving file /tmp/toll.sh...
Wrote /tmp/toll.sh
delete-backward-char: Text is read-only
user-error: End of history; no default available [2 times]
funcall-interactively: End of buffer [2 times]

Configured using:
 'configure --prefix=/usr/ --mandir=/usr/share/man/
 --infodir=/usr/share/info/ --with-x-toolkit=no --without-makeinfo
 --with-xpm --with-jpeg --with-tiff --with-gif --with-png --with-x'

Configured features:
XPM JPEG TIFF GIF PNG RSVG IMAGEMAGICK SOUND GPM DBUS GSETTINGS GLIB
NOTIFY INOTIFY ACL LIBSELINUX GNUTLS LIBXML2 FREETYPE HARFBUZZ M17N_FLT
LIBOTF XFT ZLIB OLDXMENU X11 XDBE XIM THREADS LIBSYSTEMD PDUMPER LCMS2
GMP

Important settings:
  value of $EMACSLOADPATH: /home/bronger/.emacs.d/lisp:
  value of $LC_MONETARY: de_DE.UTF-8
  value of $LC_NUMERIC: de_DE.UTF-8
  value of $LC_TIME: de_DE.UTF-8
  value of $LANG: de_DE.UTF-8
  value of $XMODIFIERS: @im=fcitx
  locale-coding-system: utf-8-unix

Major mode: Shell-script

Minor modes in effect:
  shell-dirtrack-mode: t
  sh-electric-here-document-mode: t
  TeX-PDF-mode: t
  global-auto-revert-mode: t
  savehist-mode: t
  display-time-mode: t
  desktop-save-mode: t
  global-eldoc-mode: t
  electric-indent-mode: t
  mouse-wheel-mode: t
  global-font-lock-mode: t
  font-lock-mode: t
  auto-composition-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t
  line-number-mode: t

Load-path shadows:
/home/bronger/.emacs.d/elpa/auctex-12.1.2/tex-site hides /home/bronger/.emacs.d/lisp/tex-site
/home/bronger/.emacs.d/lisp/cmake-mode hides /usr/share/emacs/site-lisp/cmake-mode

Features:
(shadow sort mail-extr emacsbug sendmail elec-pair reftex-dcr reftex
reftex-loaddefs reftex-vars font-latex latexenc tex-mode cl-extra
help-mode vc-git diff-mode python tramp-sh tramp tramp-loaddefs trampver
tramp-integration files-x tramp-compat ucs-normalize shell
graphviz-dot-mode taskjuggler-mode skeleton darkroom cql-mode sql view
rust-mode swift-mode go-errcheck go-mode url url-proxy url-privacy
url-expand url-methods url-history url-cookie url-domsuf url-util
mailcap find-file ffap etags fileloop xref project yaml-mode
dockerfile-mode rx sh-script smie executable dired-x adaptive-wrap
org-duration org-rmail org-mhe org-irc org-info org-gnus nnir gnus-sum
gnus-group gnus-undo gnus-start gnus-cloud nnimap nnmail mail-source
utf7 netrc nnoo parse-time gnus-spec gnus-int gnus-range message rmc
puny rfc822 mml mml-sec epa derived epg mm-decode mm-bodies mm-encode
mail-parse rfc2231 mailabbrev gmm-utils mailheader gnus-win gnus
nnheader gnus-util rmail rmail-loaddefs rfc2047 rfc2045 ietf-drums
text-property-search mail-utils wid-edit org-docview doc-view jka-compr
image-mode dired dired-loaddefs org-bibtex bibtex org-bbdb org-w3m
org-agenda ob-python org-element avl-tree generator org org-macro
org-footnote org-pcomplete pcomplete org-list org-faces org-entities
time-date noutline outline org-version ob-emacs-lisp ob ob-tangle
org-src ob-ref ob-lob ob-table ob-keys ob-exp ob-comint ob-core ob-eval
org-compat org-macs org-loaddefs format-spec find-func server mmm-mode
mmm-univ mmm-class mmm-region mmm-auto mmm-vars mmm-utils mmm-compat cl
rst browse-kill-ring bbdb-autoloads bbdb timezone cal-china lunar solar
cal-dst cal-bahai cal-islam cal-hebrew holidays hol-loaddefs appt
diary-lib diary-loaddefs cal-menu calendar cal-loaddefs preview
prv-emacs reporter tex-buf latex easy-mmode latex-flymake flymake-proc
flymake compile comint ansi-color ring warnings thingatpt tex-ispell
tex-style tex dbus xml crm advice mm-util mail-prsvr autorevert
filenotify edmacro kmacro savehist time desktop frameset delsel
cus-start cus-load mule-util tex-site info package easymenu epg-config
url-handlers url-parse auth-source cl-seq eieio eieio-core cl-macs
eieio-loaddefs password-cache json subr-x map url-vars seq byte-opt gv
bytecomp byte-compile cconv cl-loaddefs cl-lib tooltip eldoc electric
uniquify ediff-hook vc-hooks lisp-float-type mwheel term/x-win x-win
term/common-win x-dnd tool-bar dnd fontset image regexp-opt fringe
tabulated-list replace newcomment text-mode elisp-mode lisp-mode
prog-mode register page menu-bar rfn-eshadow isearch timer select
scroll-bar mouse jit-lock font-lock syntax facemenu font-core
term/tty-colors frame 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 charscript charprop case-table epa-hook jka-cmpr-hook
help simple abbrev obarray minibuffer cl-preloaded nadvice loaddefs
button faces cus-face macroexp files text-properties overlay sha1 md5
base64 format env code-pages mule custom widget hashtable-print-readable
backquote threads dbusbind inotify lcms2 dynamic-setting
system-font-setting font-render-setting x multi-tty make-network-process
emacs)

Memory information:
((conses 16 416690 21448)
 (symbols 48 32196 2)
 (strings 32 104349 5670)
 (string-bytes 1 3512424)
 (vectors 16 61225)
 (vector-slots 8 704206 27798)
 (floats 8 790 39)
 (intervals 56 599 18)
 (buffers 992 19))

-- 
Torsten Bronger

bug#42304: 27.0.50; Emacs does not adjust to global font scaling anymore

[Eli Zaretskii]

> From: Torsten Bronger <bronger@physik.rwth-aachen.de>
> Date: Fri, 10 Jul 2020 09:06:43 +0200
> 
> If I re-scale all fonts on my Gnome desktop with e.g.
> 
> dconf write /org/gnome/desktop/interface/text-scaling-factor 2.0
> 
> Emacs is the only application that does not change its font size
> accordingly.  Instead, I have to re-start Emacs.  This used to work
> properly.  The problem was introduced with commit f208d5ae77.
> 
> 
> 
> 
> 
> In GNU Emacs 27.0.50 (build 1, x86_64-pc-linux-gnu)
>  of 2020-07-10 built on brad
> Repository revision: 3f9d96e3d70e94768add7d89ffcb94be7de4597e
> Repository branch: HEAD

You seem to be using a very old version of the Emacs repository.
Could you please try building the latest emacs-27 branch, or the
latest pretest 27.0.91 of the upcoming Emacs 27?  You can find the
pretest on alpha.gnu.org.

Thanks.

bug#42304: 27.0.50; Emacs does not adjust to global font scaling anymore

[Torsten Bronger]

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Hallöchen!

Eli Zaretskii writes:

>> From: Torsten Bronger <bronger@physik.rwth-aachen.de>
>> Date: Fri, 10 Jul 2020 09:06:43 +0200
>> 
>> If I re-scale all fonts on my Gnome desktop with e.g.
>> 
>> dconf write /org/gnome/desktop/interface/text-scaling-factor 2.0
>> 
>> Emacs is the only application that does not change its font size
>> accordingly.  Instead, I have to re-start Emacs.  This used to work
>> properly.  The problem was introduced with commit f208d5ae77.
>> 
>> In GNU Emacs 27.0.50 (build 1, x86_64-pc-linux-gnu)
>>  of 2020-07-10 built on brad
>> Repository revision: 3f9d96e3d70e94768add7d89ffcb94be7de4597e
>> Repository branch: HEAD
>
> You seem to be using a very old version of the Emacs repository.
> Could you please try building the latest emacs-27 branch, or the
> latest pretest 27.0.91 of the upcoming Emacs 27?  You can find the
> pretest on alpha.gnu.org.

I bisected between

    commit 9ade7ea7b77ec40c16deb4dff139ce7127a703e2 (HEAD -> master, origin/master, origin/HEAD)
    Author: João Távora <joaotavora@gmail.com>
    Date:   Fri Jul 10 01:47:10 2020 +0100

and

    commit 7c7ee1dd52239ecc3665b7542bd5e0ebc9b74795 (grafted, HEAD)
    Author: Glenn Morris <rgm@gnu.org>
    Date:   Mon Apr 29 09:12:53 2019 -0700

and the commit mentioned in my report introduced the problem.  (Note
that the following commit 3f9d96e3d made it compilable.)

Tschö,
Torsten.

-- 
Torsten Bronger

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bug#42304: 27.0.50; Emacs does not adjust to global font scaling anymore

[Robert Pluim]

>>>>> On Fri, 10 Jul 2020 10:01:00 +0200, Torsten Bronger <bronger@physik.rwth-aachen.de> said:

    Torsten> Hallöchen!
    Torsten> Eli Zaretskii writes:

    >>> From: Torsten Bronger <bronger@physik.rwth-aachen.de>
    >>> Date: Fri, 10 Jul 2020 09:06:43 +0200
    >>> 
    >>> If I re-scale all fonts on my Gnome desktop with e.g.
    >>> 
    >>> dconf write /org/gnome/desktop/interface/text-scaling-factor 2.0
    >>> 
    >>> Emacs is the only application that does not change its font size
    >>> accordingly.  Instead, I have to re-start Emacs.  This used to work
    >>> properly.  The problem was introduced with commit f208d5ae77.

And if you run 'configure --without-harfbuzz' does the problem go
away?

Robert

bug#42304: 27.0.50; Emacs does not adjust to global font scaling anymore

[Lars Ingebrigtsen]

Robert Pluim <rpluim@gmail.com> writes:

>     >>> If I re-scale all fonts on my Gnome desktop with e.g.
>     >>> 
>     >>> dconf write /org/gnome/desktop/interface/text-scaling-factor 2.0
>     >>> 
>     >>> Emacs is the only application that does not change its font size
>     >>> accordingly.  Instead, I have to re-start Emacs.

I can reproduce this problem in Emacs 28.

> And if you run 'configure --without-harfbuzz' does the problem go
> away?

No, that has no effect.

-- 
(domestic pets only, the antidote for overdose, milk.)
   bloggy blog: http://lars.ingebrigtsen.no

bug#42304: 27.0.50; Emacs does not adjust to global font scaling anymore

[Robert Pluim]

>>>>> On Sat, 31 Jul 2021 16:23:47 +0200, Lars Ingebrigtsen <larsi@gnus.org> said:

    Lars> Robert Pluim <rpluim@gmail.com> writes:
    >> >>> If I re-scale all fonts on my Gnome desktop with e.g.
    >> >>> 
    >> >>> dconf write /org/gnome/desktop/interface/text-scaling-factor 2.0
    >> >>> 
    >> >>> Emacs is the only application that does not change its font size
    >> >>> accordingly.  Instead, I have to re-start Emacs.

    Lars> I can reproduce this problem in Emacs 28.

I think attempting to get this to work with impure gtk is a losing
proposition. It doesnʼt work in the pgtk branch either. Harano-san,
would you have any suggestions?

Robert
-- 

bug#42304: 27.0.50; Emacs does not adjust to global font scaling anymore

[Torsten Bronger]

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Hallöchen!

Torsten Bronger writes:

> If I re-scale all fonts on my Gnome desktop with e.g.
>
> dconf write /org/gnome/desktop/interface/text-scaling-factor 2.0
>
> Emacs is the only application that does not change its font size
> accordingly.  Instead, I have to re-start Emacs.  This used to
> work properly.  The problem was introduced with commit f208d5ae77.

This still is an issue, also on Wayland and pgtk.  The commit
f208d5ae77 that introduced the problem is long but since
--without-harfbuzz does not change anything, much of the commit diff
can be ignored, I suspect.

@Po Lu: Since you seem to be into the low-level display code
currently, I shamelessly Cc’ed you.  Of course, this is not a
demand but possibly you have an idea.

Regards,
Torsten.

-- 
Torsten Bronger

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bug#42304: 27.0.50; Emacs does not adjust to global font scaling anymore

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

Torsten Bronger <bronger@physik.rwth-aachen.de> writes:

> This still is an issue, also on Wayland and pgtk.  The commit
> f208d5ae77 that introduced the problem is long but since
> --without-harfbuzz does not change anything, much of the commit diff
> can be ignored, I suspect.
>
> @Po Lu: Since you seem to be into the low-level display code
> currently, I shamelessly Cc’ed you.  Of course, this is not a
> demand but possibly you have an idea.

I don't understand how that could ever have worked, since there was
never any code to handle the GNOME text scaling factor outside the PGTK
port.

In the PGTK port, that factor is only applied on startup by the toolkit
itself.  We don't have any code to recreate fonts and cairo surfaces
when it changes.

So it would be helpful to see exactly what caused Emacs to dynamically
adjust the default font size before Harfbuzz shaping was introduced, and
why it doesn't work afterwards.

bug#42304: 27.0.50; Emacs does not adjust to global font scaling anymore

[Eli Zaretskii]

> Cc: 42304@debbugs.gnu.org
> Date: Wed, 18 May 2022 14:40:32 +0800
> From:  Po Lu via "Bug reports for GNU Emacs,
>  the Swiss army knife of text editors" <bug-gnu-emacs@gnu.org>
> 
> So it would be helpful to see exactly what caused Emacs to dynamically
> adjust the default font size before Harfbuzz shaping was introduced, and
> why it doesn't work afterwards.

I'm surprised that HarfBuzz has any effect whatsoever on selection of
fonts.