From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Eli Zaretskii Newsgroups: gmane.emacs.bidi,gmane.emacs.devel Subject: Re: Mixed L2R and R2L paragraphs and horizontal scroll Date: Sun, 31 Jan 2010 20:02:56 +0200 Message-ID: <83aavui23z.fsf@gnu.org> References: <83tyu3iu6b.fsf@gnu.org> <4B645FF4.30205@gmx.at> <83ockbil1v.fsf@gnu.org> <4B646AD3.1010102@gmx.at> <83mxzviio5.fsf@gnu.org> <4B647AE5.5090001@gmx.at> <83ljffif09.fsf@gnu.org> <4B648C6E.8080905@gmx.at> <83eil7i84h.fsf@gnu.org> <4B654F24.5020603@gmx.at> Reply-To: Eli Zaretskii NNTP-Posting-Host: lo.gmane.org X-Trace: ger.gmane.org 1264961014 6465 80.91.229.12 (31 Jan 2010 18:03:34 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Sun, 31 Jan 2010 18:03:34 +0000 (UTC) Cc: emacs-bidi@gnu.org, emacs-devel@gnu.org To: martin rudalics Original-X-From: emacs-bidi-bounces+gnu-emacs-bidi=m.gmane.org@gnu.org Sun Jan 31 19:03:31 2010 Return-path: Envelope-to: gnu-emacs-bidi@m.gmane.org Original-Received: from lists.gnu.org ([199.232.76.165]) by lo.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1Nbe8s-0001Ct-PE for gnu-emacs-bidi@m.gmane.org; Sun, 31 Jan 2010 19:03:27 +0100 Original-Received: from localhost ([127.0.0.1]:51975 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1Nbe8s-00089k-5l for gnu-emacs-bidi@m.gmane.org; Sun, 31 Jan 2010 13:03:26 -0500 Original-Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1Nbe8p-00088s-7G for emacs-bidi@gnu.org; Sun, 31 Jan 2010 13:03:23 -0500 Original-Received: from [199.232.76.173] (port=51127 helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1Nbe8o-00088X-TA for emacs-bidi@gnu.org; Sun, 31 Jan 2010 13:03:22 -0500 Original-Received: from Debian-exim by monty-python.gnu.org with spam-scanned (Exim 4.60) (envelope-from ) id 1Nbe8n-0001Cw-A7 for emacs-bidi@gnu.org; Sun, 31 Jan 2010 13:03:22 -0500 Original-Received: from mtaout22.012.net.il ([80.179.55.172]:36732) by monty-python.gnu.org with esmtp (Exim 4.60) (envelope-from ) id 1Nbe8i-0001By-Ej; Sun, 31 Jan 2010 13:03:21 -0500 Original-Received: from conversion-daemon.a-mtaout22.012.net.il by a-mtaout22.012.net.il (HyperSendmail v2007.08) id <0KX400H00I1MF300@a-mtaout22.012.net.il>; Sun, 31 Jan 2010 20:02:54 +0200 (IST) Original-Received: from HOME-C4E4A596F7 ([87.70.32.75]) by a-mtaout22.012.net.il (HyperSendmail v2007.08) with ESMTPA id <0KX4007JCI4RBZO0@a-mtaout22.012.net.il>; Sun, 31 Jan 2010 20:02:52 +0200 (IST) In-reply-to: <4B654F24.5020603@gmx.at> X-012-Sender: halo1@inter.net.il X-detected-operating-system: by monty-python.gnu.org: Solaris 10 (beta) X-BeenThere: emacs-bidi@gnu.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: "Discussion of Emacs support for multi-directional text." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Original-Sender: emacs-bidi-bounces+gnu-emacs-bidi=m.gmane.org@gnu.org Errors-To: emacs-bidi-bounces+gnu-emacs-bidi=m.gmane.org@gnu.org Xref: news.gmane.org gmane.emacs.bidi:481 gmane.emacs.devel:120751 Archived-At: > Date: Sun, 31 Jan 2010 10:36:36 +0100 > From: martin rudalics > CC: emacs-bidi@gnu.org, emacs-devel@gnu.org > > > Yes, and they were also flushed to the right. This is what the > > bidirectional display does. > > With bidirectional display going to the end of the first line in the > first window you earlier proposed to show > > +---------+---------+-------------------+ > |$ijk |abcdefgh$|abcdefghijk | > |$HGFEDCBA|$HGFEDCBA| KJIHGFEDCBA| > | | | | > +---------+---------+-------------------+ Yes, I did. But now I changed my mind, see below. > Now moving in the first window to the end of the second line do you want > to display > > +---------+---------+-------------------+ > |$ijk |abcdefgh$|abcdefghijk | > | KJI$|$HGFEDCBA| KJIHGFEDCBA| > | | | | > +---------+---------+-------------------+ > > or > > +---------+---------+-------------------+ > |abcdefgh$|abcdefgh$|abcdefghijk | > | KJI$|$HGFEDCBA| KJIHGFEDCBA| > | | | | > +---------+---------+-------------------+ > > or something else? I think the former of these two is TRT. The reason is simple, although it took me some time to arrive at it: column numbering. In a R2L line, columns should be numbered from the right margin of the window. Given the fact that a window's dimensions can be changed at will, and thus the horizontal position of characters in R2L lines relative to L2R lines can change, there simply isn't any other reasonable way of numbering columns of a R2L line. We will need that anyway for supporting features like indentation and tab stops in R2L paragraphs. And since the columns are numbered from the right margin, hscroll, too, should scroll R2L lines to the right when L2R lines are hscrolled to the left. That's the only reasonable way of generalizing the current unidirectional hscroll, IMO. It also preserves the semantics of window-hscroll (modulo the fact that R2L lines are scrolled from the right margin, not the left one). Makes sense?