From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!.POSTED.blaine.gmane.org!not-for-mail From: "Basil L. Contovounesios" Newsgroups: gmane.emacs.bugs Subject: bug#35721: 27.0.50; Strange Arabic shaping behavior Date: Thu, 16 May 2019 21:54:10 +0100 Message-ID: <87y336ce8d.fsf@tcd.ie> References: <87h89ycpnw.fsf@tcd.ie> <83mujp9in8.fsf@gnu.org> <83d0kkao99.fsf@gnu.org> <83v9yacyvp.fsf@gnu.org> <20190516134508.GH1802@macbook.localdomain> <83imuacx00.fsf@gnu.org> <20190516142000.GI1802@macbook.localdomain> <83bm02cvp3.fsf@gnu.org> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Injection-Info: blaine.gmane.org; posting-host="blaine.gmane.org:195.159.176.226"; logging-data="152917"; mail-complaints-to="usenet@blaine.gmane.org" User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/27.0.50 (gnu/linux) Cc: Khaled Hosny , behdad@behdad.org, 35721@debbugs.gnu.org To: Eli Zaretskii Original-X-From: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane.org@gnu.org Thu May 16 22:55:17 2019 Return-path: Envelope-to: geb-bug-gnu-emacs@m.gmane.org Original-Received: from lists.gnu.org ([209.51.188.17]) by blaine.gmane.org with esmtps (TLS1.0:RSA_AES_256_CBC_SHA1:256) (Exim 4.89) (envelope-from ) id 1hRNPI-000dc8-NZ for geb-bug-gnu-emacs@m.gmane.org; Thu, 16 May 2019 22:55:16 +0200 Original-Received: from localhost ([127.0.0.1]:35990 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1hRNPH-0004cY-BN for geb-bug-gnu-emacs@m.gmane.org; Thu, 16 May 2019 16:55:15 -0400 Original-Received: from eggs.gnu.org ([209.51.188.92]:43228) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1hRNP7-0004a4-8u for bug-gnu-emacs@gnu.org; Thu, 16 May 2019 16:55:10 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1hRNP6-0005PA-8N for bug-gnu-emacs@gnu.org; Thu, 16 May 2019 16:55:05 -0400 Original-Received: from debbugs.gnu.org ([209.51.188.43]:43055) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1hRNP6-0005OV-4Q for bug-gnu-emacs@gnu.org; Thu, 16 May 2019 16:55:04 -0400 Original-Received: from Debian-debbugs by debbugs.gnu.org with local (Exim 4.84_2) (envelope-from ) id 1hRNP4-0003t6-L1 for bug-gnu-emacs@gnu.org; Thu, 16 May 2019 16:55:03 -0400 X-Loop: help-debbugs@gnu.org Resent-From: "Basil L. Contovounesios" Original-Sender: "Debbugs-submit" Resent-CC: bug-gnu-emacs@gnu.org Resent-Date: Thu, 16 May 2019 20:55:02 +0000 Resent-Message-ID: Resent-Sender: help-debbugs@gnu.org X-GNU-PR-Message: followup 35721 X-GNU-PR-Package: emacs X-GNU-PR-Keywords: notabug Original-Received: via spool by 35721-submit@debbugs.gnu.org id=B35721.155804006014878 (code B ref 35721); Thu, 16 May 2019 20:55:02 +0000 Original-Received: (at 35721) by debbugs.gnu.org; 16 May 2019 20:54:20 +0000 Original-Received: from localhost ([127.0.0.1]:56599 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1hRNOO-0003rt-DF for submit@debbugs.gnu.org; Thu, 16 May 2019 16:54:20 -0400 Original-Received: from mail-ed1-f68.google.com ([209.85.208.68]:46679) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1hRNON-0003rh-3X for 35721@debbugs.gnu.org; Thu, 16 May 2019 16:54:19 -0400 Original-Received: by mail-ed1-f68.google.com with SMTP id f37so7083566edb.13 for <35721@debbugs.gnu.org>; Thu, 16 May 2019 13:54:18 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=tcd-ie.20150623.gappssmtp.com; s=20150623; h=from:to:cc:subject:references:date:in-reply-to:message-id :user-agent:mime-version:content-transfer-encoding; bh=YQLJ8rSmUclvV+jGsVKD0clzWaxpers3Dd7XKfpSmZo=; b=x8On3KfedYKKDLMJl5UjMt9o+75tvAoRnRhbqLdf7y0FJJxfOdGNu2gvfnwr3/M7+8 OsxN+BqKv9lDAknR1oMOsdb6Y11a9Ncj0r8h/lGOQ5UPwyuxXk111O59j3l5HEi2YRlN Ru9vOzGv8YCDv4cKwHKFKl+orwg+74vAy/cOn9uYeU795ui24ZuegzDZUGOMQznXPTk0 aj8bp3HaY2WiJzNhpsqz6CbHNMhYEziYGtY2YKDWZcmnjIdC0DhyTxr8cmyk2Z9hKnOo OxslJYGnAqvny7q8jPZR0p/C/aB7MQ/hqHN7mk1pEYqwoVoIGp0mkJr8Hg6n6Ta2eYfO IJfQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:references:date:in-reply-to :message-id:user-agent:mime-version:content-transfer-encoding; bh=YQLJ8rSmUclvV+jGsVKD0clzWaxpers3Dd7XKfpSmZo=; b=D1CYHvsDWGYghlmrIsLe21rdxa+7WqO155fhBzi9tst+xLpruaG2Cv78JRSzDhYELY M+OZKw6CZ09WJefWuN75wqkEAeIAcMRRXybrfr5nXLIhW2T1tnTF0xXbB0sy1RHjZlfU uJ71+h11mBPOscp4BaAMCapKHnOp70o96Omk8I1r1yQBF/x5sUs34SQSnJwOnzcPYBpI WzGLCDvATiZjZK4iOQQm43uM6mtFfFbyFkjqzZf1QnXF2DyVeLyzn/7p/V1SGMFhzhMo gqIVfNP4aguTFTCrl0kMOOHYw8L5256o8nbsxSBEsfdbe6ML/Ukfm7KTFjEtPxsdur/F mirA== X-Gm-Message-State: APjAAAUq4PhwZcmqO+U+ZjhvfBnUCxqs5ZGWDVfuY+LC+VT2MqvVWupL S3ZVazYJbfuvSBHeZR6CnT5byQ== X-Google-Smtp-Source: APXvYqxLWaeLfaICeVYknPtE1hkOVLzktzxKVw/0JTZJH/DjV6BlDjt9TPuxTTjfLHROhmwSv0s1vQ== X-Received: by 2002:a50:ac5d:: with SMTP id w29mr53561024edc.121.1558040053188; Thu, 16 May 2019 13:54:13 -0700 (PDT) Original-Received: from localhost ([2a02:8084:20e2:c380:6fa:38d6:1fce:ddb3]) by smtp.gmail.com with ESMTPSA id d24sm2163183edb.5.2019.05.16.13.54.12 (version=TLS1_3 cipher=AEAD-AES256-GCM-SHA384 bits=256/256); Thu, 16 May 2019 13:54:12 -0700 (PDT) In-Reply-To: <83bm02cvp3.fsf@gnu.org> (Eli Zaretskii's message of "Thu, 16 May 2019 17:36:56 +0300") X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.18 Precedence: list X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 209.51.188.43 X-BeenThere: bug-gnu-emacs@gnu.org List-Id: "Bug reports for GNU Emacs, the Swiss army knife of text editors" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane.org@gnu.org Original-Sender: "bug-gnu-emacs" Xref: news.gmane.org gmane.emacs.bugs:159416 Archived-At: Eli Zaretskii writes: > tags 35721 notabug > thanks > >> Date: Thu, 16 May 2019 16:20:00 +0200 >> From: Khaled Hosny >> Cc: behdad@behdad.org, contovob@tcd.ie, handa@gnu.org, >> 35721@debbugs.gnu.org >>=20 >> On Thu, May 16, 2019 at 05:08:47PM +0300, Eli Zaretskii wrote: >> > The main point of this bug report is about the other part, though: how >> > sheen should be displayed when using DejaVu Sans Mono. >>=20 >> I don=E2=80=99t think there is a right answer here. Glyphs can have -ve = right or >> left side bearings, so if the graphics context has no room on the either >> side then I think it is expected that the glyph would be truncated. This >> is not Arabic specific (e.g. italic f often have -ve right side >> bearing, in variable width fonts at least). > > OK, thanks. > > Basil, is it okay with you to close this bug, given these comments? Thanks to everyone for your explanations. I now understand why the truncation happens, and why mark activation is expected to affect character composition. The issue that prompted this report, however, is the alternating toggling of certain character compositions while typing in a separate part of the buffer (steps 9 and 10 in the OP), where no face change is involved. I'm sorry for not making this clearer from the outset. If you think this is unsurprising behaviour given the display engine's current implementation, I don't mind if you close this issue. Otherwise, perhaps either this issue can be retitled, or I can submit a new issue focussing only on that part of the OP. Sorry for the confusion, and thanks again. --=20 Basil