Subject: bug#15886: closed (Re: bug#15886: 24.3.50; Incorrect window-text-height with non-zero line-spacing)

From: [email-masked] (GNU bug Tracking System)
Date: Wed, 28 Oct 2020 07:41:02 +0000

Your bug report

#15886: 24.3.50; Incorrect window-text-height with non-zero line-spacing

which was filed against the emacs package, has been closed.

The explanation is attached below, along with your original report.
If you require more details, please reply to [email-masked].

-- 
15886: http://debbugs.gnu.org/cgi/bugreport.cgi?bug=15886
GNU Bug Tracking System
Contact [email-masked] with problems

Subject: Re: bug#15886: 24.3.50; Incorrect window-text-height with non-zero line-spacing
From: Stefan Kangas <[email-masked]>
To: Eli Zaretskii <[email-masked]>
Cc: Robert Dallas Gray <[email-masked]>, [email-masked]
Date: Wed, 28 Oct 2020 00:39:55 -0700
List-Id: <debbugs-submit.debbugs.gnu.org>

Eli Zaretskii <[email-masked]> writes:

>> And, if it's impractical to fix this, is there a way to set the
>> height of the window in pixels rather than lines so that the same
>> effect can be achieved?
>
> What makes you think that setting window height in pixels would solve
> this issue?  Granted, the "jitter" would probably be smaller, but a
> human eye can easily spot even a 1-pixel jitter, and be no less
> annoyed.
>
> What I'm trying to tell is that it is simply impossible to control the
> Emacs display in Lisp to such a degree of precision, not with the way
> the display engine is currently designed and implemented.  Whoever
> designs packages which try to do that should be acutely aware of these
> limitations in the first place, and if they don't avert her, at least
> mention them in some prominent place.

>From skimming this thread, it contains a long discussion that ultimately
ends up in the conclusion that what is requested is fundamentally not
possible to achieve with our current display engine.

So lacking any other updates within 7 years, and seeing nothing
actionable, it seems unlikely that we'll make any progress here.
I'm therefore closing this bug report.

If that conclusion is incorrect and there is more to do here, please
reply to this email (use "Reply to all" in your email client) and we can
reopen the bug report.

Subject: 24.3.50; Incorrect window-text-height with non-zero line-spacing
From: Robert Dallas Gray <[email-masked]>
To: [email-masked]
Date: Wed, 13 Nov 2013 19:23:19 +0000
List-Id: <debbugs-submit.debbugs.gnu.org>

On a graphical display, when `line-spacing' is non-zero,
`window-text-height' reports an incorrect number; equally,
`set-window-text-height' can't be used properly. This impacts on
libraries which use `set-window-text-height' e.g. to attempt to size a
window accurately.

To reproduce:
In a graphical display, `M-: (setq line-spacing 5)', then `M-:
(window-text-height)'. Note the incorrect result. 

In GNU Emacs 24.3.50.1 (x86_64-apple-darwin13.0.0, NS apple-appkit-1265.00)
of 2013-11-10 on Pud.local
Windowing system distributor `Apple', version 10.3.1265
Configured using:
`configure --prefix=/usr/local/Cellar/emacs/HEAD --without-dbus
--enable-locallisppath=/usr/local/share/emacs/site-lisp
--infodir=/usr/local/Cellar/emacs/HEAD/share/info/emacs
--without-gnutls --with-ns --disable-ns-self-contained'

Important settings:
  value of $LANG: en_GB.UTF-8
  locale-coding-system: utf-8-unix
  default enable-multibyte-characters: t

Major mode: Emacs-Lisp

Minor modes in effect:
  flycheck-mode: t
  show-smartparens-mode: t
  smartparens-mode: t
  global-auto-complete-mode: t
  auto-complete-mode: t
  linum-mode: t
  shell-dirtrack-mode: t
  project-persist-mode: t
  global-auto-revert-mode: t
  ido-everywhere: t
  delete-selection-mode: t
  tooltip-mode: t
  mouse-wheel-mode: t
  menu-bar-mode: t
  file-name-shadow-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
  global-visual-line-mode: t
  visual-line-mode: t
  transient-mark-mode: t

Recent input:
<C-down> <C-down> <C-down> C-x C-s <C-down> <C-down> 
<C-down> <C-down> <C-down> <C-down> <C-down> <C-up> 
<down> <up> <left> C-c <down> C-c . d e l e t e <return> 
<down-mouse-1> <mouse-1> <down-mouse-1> <mouse-1> <down-mouse-1> 
<mouse-1> <down-mouse-1> <mouse-1> <return> ; ; SPC 
p a c k a g e - d e l e t e SPC h a s SPC d i f f e 
r e n t SPC s i g n a t u r e s SPC d e p e d i n <backspace> 
<backspace> <backspace> n d i n g SPC o n SPC e m a 
c s SPC v e r s i o n , <return> ; ; SPC b u t SPC 
u s i n g SPC t h e SPC f i r s t SPC a r g SPC s h 
o u l d SPC h a n d l e SPC b o t h <right> <left> 
<left> <left> <left> <left> <left> <left> <left> <left> 
<left> <left> <left> <left> <left> <left> <left> <left> 
<left> <left> <left> <left> <left> <left> <left> <left> 
<left> <right> <right> <left> <left> <left> <left> 
<left> <left> <left> <left> <left> <M-backspace> t 
a k i n g SPC <right> <right> <right> <right> <right> 
<right> <right> <right> <right> <right> <right> <right> 
<right> <right> <left> SPC f r o m SPC a d v i c e 
<right> C-x C-s C-c <down> C-c <up> C-c <right> C-s 
a d v C-s <right> <right> <down> <down> <down> <down> 
<down> <wheel-up> <double-wheel-up> <triple-wheel-up> 
<triple-wheel-up> <triple-wheel-up> <triple-wheel-up> 
<triple-wheel-up> <triple-wheel-up> <triple-wheel-up> 
<triple-wheel-up> <triple-wheel-up> <triple-wheel-up> 
<triple-wheel-up> <triple-wheel-up> <triple-wheel-up> 
<triple-wheel-up> <triple-wheel-up> <triple-wheel-up> 
<triple-wheel-up> <triple-wheel-up> <triple-wheel-up> 
<triple-wheel-up> <triple-wheel-up> <triple-wheel-up> 
<triple-wheel-up> <triple-wheel-up> <triple-wheel-up> 
<triple-wheel-up> <triple-wheel-up> <triple-wheel-up> 
<triple-wheel-up> <triple-wheel-up> <triple-wheel-up> 
<triple-wheel-up> <triple-wheel-up> <triple-wheel-up> 
<triple-wheel-up> <triple-wheel-up> <triple-wheel-up> 
<triple-wheel-up> <down-mouse-1> <mouse-1> M-x r e 
p o <return>

Recent messages:
FlyC: You should have a section marked ";;; Commentary:"
FlyC: You should have a section marked ";;; Code:"
FlyC: The first line should be of the form: ";;; package --- Summary"
FlyC: You should have a section marked ";;; Commentary:"
FlyC: You should have a section marked ";;; Code:"
Saving file /Users/robertdallasgray/.emacs.d/pallet/test/pallet-test.el...
Wrote /Users/robertdallasgray/.emacs.d/pallet/test/pallet-test.el
Saving file /Users/robertdallasgray/.emacs.d/pallet/test/pallet-test.el...
Wrote /Users/robertdallasgray/.emacs.d/pallet/test/pallet-test.el
Mark saved where search started
scroll-down-command: Beginning of buffer [18 times]

Load-path shadows:
/Users/robertdallasgray/.emacs.d/.cask/24.3.50.1/elpa/flycheck-20131108.1337/.dir-locals hides /Users/robertdallasgray/.emacs.d/.cask/24.3.50.1/elpa/fringe-helper-20130519.1641/.dir-locals
~/.emacs.d/custom hides /usr/local/Cellar/emacs/HEAD/share/emacs/24.3.50/lisp/custom
/Users/robertdallasgray/.emacs.d/.cask/24.3.50.1/elpa/flycheck-20131108.1337/.dir-locals hides /usr/local/Cellar/emacs/HEAD/share/emacs/24.3.50/lisp/gnus/.dir-locals

Features:
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mm-bodies mm-encode mail-parse rfc2231 mailabbrev gmm-utils mailheader
sendmail rfc2047 rfc2045 ietf-drums mm-util mail-prsvr mail-utils
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shell-pop term ehelp electric windmove hl-line sr-speedbar speedbar
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make-mode vc-git desktop frameset flycheck find-func help-mode easy-kill
graphene-smartparens-config smartparens-config smartparens-html
smartparens thingatpt auto-complete-config auto-complete popup linum
imenu-anywhere imenu graphene-theme solarized-light-theme
solarized-definitions uniquify readline-complete shell pcomplete comint
ansi-color ring graphene graphene-look graphene-osx-defaults
exec-path-from-shell graphene-keys graphene-projects project-persist
edmacro kmacro graphene-speedbar graphene-env autorevert filenotify smex
ido graphene-editing web-mode disp-table delsel
graphene-helper-functions advice noflet rx info easymenu cask help-fns
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cl-lib package server time-date tooltip ediff-hook vc-hooks
lisp-float-type mwheel ns-win tool-bar dnd fontset image regexp-opt
fringe tabulated-list newcomment lisp-mode prog-mode register page
menu-bar rfn-eshadow timer select scroll-bar mouse jit-lock font-lock
syntax facemenu font-core frame cham georgian utf-8-lang misc-lang
vietnamese tibetan thai tai-viet lao korean japanese hebrew greek
romanian slovak czech european ethiopic indian cyrillic chinese
case-table epa-hook jka-cmpr-hook help simple abbrev minibuffer 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 make-network-process cocoa ns
multi-tty emacs)