From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.blaine.gmane.org!not-for-mail From: Stefan Kangas Newsgroups: gmane.emacs.bugs Subject: bug#44632: 27.1.50; Left-to-right Arabic shaping breaks at property bounds Date: Mon, 11 Oct 2021 05:36:14 -0700 Message-ID: References: <878sb4p0sk.fsf@brutus.matara> <83k0uouh38.fsf@gnu.org> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214"; logging-data="20263"; mail-complaints-to="usenet@ciao.gmane.io" User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/28.0.60 (gnu/linux) Cc: 44632@debbugs.gnu.org, Thamer Mahmoud To: Eli Zaretskii Original-X-From: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane-mx.org@gnu.org Mon Oct 11 14:39:24 2021 Return-path: Envelope-to: geb-bug-gnu-emacs@m.gmane-mx.org Original-Received: from lists.gnu.org ([209.51.188.17]) by ciao.gmane.io with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1mZuaR-00055k-Td for geb-bug-gnu-emacs@m.gmane-mx.org; Mon, 11 Oct 2021 14:39:23 +0200 Original-Received: from localhost ([::1]:35344 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1mZuaQ-0000ch-25 for geb-bug-gnu-emacs@m.gmane-mx.org; Mon, 11 Oct 2021 08:39:22 -0400 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]:44614) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1mZuYA-0007B2-H4 for bug-gnu-emacs@gnu.org; Mon, 11 Oct 2021 08:37:03 -0400 Original-Received: from debbugs.gnu.org ([209.51.188.43]:45466) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1mZuYA-0004Dd-8Z for bug-gnu-emacs@gnu.org; Mon, 11 Oct 2021 08:37:02 -0400 Original-Received: from Debian-debbugs by debbugs.gnu.org with local (Exim 4.84_2) (envelope-from ) id 1mZuYA-0006rG-4f for bug-gnu-emacs@gnu.org; Mon, 11 Oct 2021 08:37:02 -0400 X-Loop: help-debbugs@gnu.org Resent-From: Stefan Kangas Original-Sender: "Debbugs-submit" Resent-CC: bug-gnu-emacs@gnu.org Resent-Date: Mon, 11 Oct 2021 12:37:02 +0000 Resent-Message-ID: Resent-Sender: help-debbugs@gnu.org X-GNU-PR-Message: followup 44632 X-GNU-PR-Package: emacs Original-Received: via spool by 44632-submit@debbugs.gnu.org id=B44632.163395578226273 (code B ref 44632); Mon, 11 Oct 2021 12:37:02 +0000 Original-Received: (at 44632) by debbugs.gnu.org; 11 Oct 2021 12:36:22 +0000 Original-Received: from localhost ([127.0.0.1]:57007 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1mZuXW-0006pf-6u for submit@debbugs.gnu.org; Mon, 11 Oct 2021 08:36:22 -0400 Original-Received: from mail-pj1-f52.google.com ([209.85.216.52]:35462) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1mZuXU-0006pO-6L for 44632@debbugs.gnu.org; Mon, 11 Oct 2021 08:36:20 -0400 Original-Received: by mail-pj1-f52.google.com with SMTP id d13-20020a17090ad3cd00b0019e746f7bd4so14653101pjw.0 for <44632@debbugs.gnu.org>; Mon, 11 Oct 2021 05:36:20 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:in-reply-to:references:user-agent :mime-version:date:message-id:subject:to:cc :content-transfer-encoding; bh=gjEfo5/FNZMI2I5Yu8wpeuK4zINirLn7LoOYMmiCJmo=; b=CO9EiD6JyMv96fHSRAr/Sh5mN0EAxL1+/pWAkEAgt2MN2vyZiLpbJ9+pLtuxdy722S 52gQlEV8EiPK/S5LI1Rm+WlFFDz1cSzocI8b7nU/YGWlhcVdKavWh45CRjgqUZQO/9B2 Q9mOQtgim2xUKstB1LcBA81HbLycrYGm6SHqZZTP2faKZ3VydLnhtJCxCuELJTwHEDDo MwCGj9sxhcC7xYvNKgfC4ATmkEMlgTijzx1QahEK+L6lNfWl4T04b4VBoZl7AnTDdCLx 1qQb5cZ6pPw5FKr16Rq31oLj1jXuYZ2gpHitsmBWvmvk9oCLuw1ySggoFf/MZNi0U1U6 kCXQ== X-Gm-Message-State: AOAM533C21StOkG+qYfUSS5MD4IVid6vTQ6vXpwtro0eEX2FGn2IoLrq Te/84vUWJqKQ7haqq/UHqwU0PeqDxokovlI1nWx8G9Ka X-Google-Smtp-Source: ABdhPJyqkLcYeXE1BAS+ezZS30Ho4+XOcVYYi6Ro+AEJj+NCII9oAV5JjKngHi9kcIi8dkN8oW/x2B4KE8qQyS93vjc= X-Received: by 2002:a17:902:6b07:b0:13e:d5ba:3d8f with SMTP id o7-20020a1709026b0700b0013ed5ba3d8fmr24374700plk.32.1633955774615; Mon, 11 Oct 2021 05:36:14 -0700 (PDT) Original-Received: from 753933720722 named unknown by gmailapi.google.com with HTTPREST; Mon, 11 Oct 2021 05:36:14 -0700 In-Reply-To: <83k0uouh38.fsf@gnu.org> (Eli Zaretskii's message of "Sat, 14 Nov 2020 16:51:39 +0200") X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.18 Precedence: list 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-mx.org@gnu.org Original-Sender: "bug-gnu-emacs" Xref: news.gmane.io gmane.emacs.bugs:216898 Archived-At: tags 44632 + wontfix close 44632 thanks Eli Zaretskii writes: >> From: Thamer Mahmoud >> Date: Sat, 14 Nov 2020 15:42:35 +0300 >> >> (with-current-buffer-window "*shaping testcase*" nil nil >> (insert "L2R =D8=B9=D8=B1=D8=A8=D9=8A" "\n\n") >> (insert "=D8=B9=D8=B1=D8=A8=D9=8A") >> (put-text-property 5 6 'face 'highlight) >> (put-text-property 11 12 'face 'highlight)) >> >> 2. Notice the AIN(=D8=B9) in the L2R paragraph has the wrong shape. > > This is a known limitation of the current Emacs display engine: it > cannot shape text across face changes. All the text that needs to be > shaped must have the same face. This problem has existed since Emacs > 21. > > Fixing this limitation would require a more or less complete redesign > of how the display engine scans the buffer text, or maybe some radical > changes in how character composition is handled. Until one of these > changes, this problem will remain unsolved, sorry. Since this is a known limitation, I think it unfortunately doesn't make sense to keep this bug open. If anyone wants to work on a redesign of the display engine, they will probably not do that due to this bug. I guess it would be good if we could have a list somewhere of the known limitations, so if anyone knows about something like that please add it. But for now, I'm closing this as wontfix.