all messages for Emacs-related lists mirrored at yhetil.org
 help / color / mirror / code / Atom feed
From: Richard Wordingham via "Bug reports for GNU Emacs, the Swiss army knife of text editors" <bug-gnu-emacs@gnu.org>
To: Eli Zaretskii <eliz@gnu.org>
Cc: 20140@debbugs.gnu.org, larsi@gnus.org
Subject: bug#20140: 24.4; M17n shaper output rejected
Date: Sun, 13 Feb 2022 21:11:52 +0000	[thread overview]
Message-ID: <20220213211152.03e2990a@JRWUBU2> (raw)
In-Reply-To: <83sfsmpmxb.fsf@gnu.org>

On Sun, 13 Feb 2022 21:49:04 +0200
Eli Zaretskii <eliz@gnu.org> wrote:

> > Date: Sat, 5 Feb 2022 22:52:51 +0000
> > From: Richard Wordingham <richard.wordingham@ntlworld.com>
> > Cc: Lars Ingebrigtsen <larsi@gnus.org>, 20140@debbugs.gnu.org
> > 
> > Sad to see that Khaled Hosny's suggestion not to use composition
> > rules seems not to have been taken.  
> 
> Btw, the _only_ reason Handa-san and now myself were able to implement
> something like the forward/backward-char-intrusive commands is that we
> DO control which parts of text are composed and which aren't.  If we
> were to follow HarfBuzz developers' advice, and were to hand all the
> text to HarfBuzz for shaping, we would need the HarfBuzz cooperation
> to implement such features in the editor.

You mean the more sophisticated mechanisms which position the cursor
intelligently.  Those two commands you named work by completely
ignoring the composition mechanism.

Correct me if I am wrong, but for Arabic, is not Emacs restricted to
typewriter-like fonts?

There would be a similar problem with the use of Tai Khuen or other
tunnelling fonts for Northern Thai if you used the current mechanism
for advancing character by character.  Tunnelling fonts write parts of
one cluster under the next.  The Tai Khuen fonts I've seen do this by
relying on characteristics of Tai Khuen spelling.  The rules don't hold
for Northern Thai, and consequently the subscript portions of
successive orthographic syllables can overwrite one another.  A
sophisticated font could check for clashes, but that needs the
orthographic syllables to be passed to the shaper together.

Richard.





  reply	other threads:[~2022-02-13 21:11 UTC|newest]

Thread overview: 35+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-03-18 22:20 bug#20140: 24.4; M17n shaper output rejected Richard Wordingham
2015-03-19  3:43 ` Eli Zaretskii
2015-03-21  8:33 ` K. Handa
2015-03-21 17:20   ` Wolfgang Jenkner
2015-03-21 17:58   ` Richard Wordingham
2015-03-21 18:26     ` Eli Zaretskii
2015-03-25 14:25     ` K. Handa
2015-03-25 21:45       ` Richard Wordingham
2015-04-05 19:48       ` Richard Wordingham
2022-02-03 21:21 ` Lars Ingebrigtsen
2022-02-04  7:37   ` Eli Zaretskii
2022-02-05 22:52     ` Richard Wordingham via Bug reports for GNU Emacs, the Swiss army knife of text editors
2022-02-06  8:11       ` Eli Zaretskii
2022-02-06 22:09         ` Richard Wordingham via Bug reports for GNU Emacs, the Swiss army knife of text editors
2022-02-07 14:04           ` Eli Zaretskii
2022-02-07 23:38             ` Richard Wordingham via Bug reports for GNU Emacs, the Swiss army knife of text editors
2022-02-08 22:13         ` Richard Wordingham via Bug reports for GNU Emacs, the Swiss army knife of text editors
2022-02-12 18:54           ` Eli Zaretskii
2022-02-13 16:04       ` Eli Zaretskii
2022-02-13 20:53         ` Richard Wordingham via Bug reports for GNU Emacs, the Swiss army knife of text editors
2022-02-14 13:19           ` Eli Zaretskii
2022-02-14 22:14             ` Richard Wordingham via Bug reports for GNU Emacs, the Swiss army knife of text editors
2022-02-15  1:27               ` Richard Wordingham via Bug reports for GNU Emacs, the Swiss army knife of text editors
2022-02-16 15:13                 ` Eli Zaretskii
2022-02-16 15:12               ` Eli Zaretskii
2022-02-16 15:11           ` Eli Zaretskii
2022-02-13 19:49       ` Eli Zaretskii
2022-02-13 21:11         ` Richard Wordingham via Bug reports for GNU Emacs, the Swiss army knife of text editors [this message]
2022-02-14 13:26           ` Eli Zaretskii
2022-02-14 23:26             ` Richard Wordingham via Bug reports for GNU Emacs, the Swiss army knife of text editors
2022-02-15 14:40               ` Eli Zaretskii
2022-02-15 21:06                 ` Richard Wordingham via Bug reports for GNU Emacs, the Swiss army knife of text editors
2022-02-16 13:15                   ` Eli Zaretskii
2022-02-16 19:01                     ` Richard Wordingham via Bug reports for GNU Emacs, the Swiss army knife of text editors
2022-02-16 19:20                       ` Eli Zaretskii

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20220213211152.03e2990a@JRWUBU2 \
    --to=bug-gnu-emacs@gnu.org \
    --cc=20140@debbugs.gnu.org \
    --cc=eliz@gnu.org \
    --cc=larsi@gnus.org \
    --cc=richard.wordingham@ntlworld.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
Code repositories for project(s) associated with this external index

	https://git.savannah.gnu.org/cgit/emacs.git
	https://git.savannah.gnu.org/cgit/emacs/org-mode.git

This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.