From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.blaine.gmane.org!not-for-mail From: Vincent Lefevre Newsgroups: gmane.emacs.bugs Subject: bug#44284: 27.1; with some Unicode font, scrolling upward with the mouse wheel actually scrolls downward when the cursor needs repositioning Date: Fri, 30 Oct 2020 21:34:53 +0100 Message-ID: <20201030203453.GF27593@zira.vinc17.org> References: <87zh46e296.fsf@cventin.lip.ens-lyon.fr> <83a6w6cmwe.fsf@gnu.org> <20201030105228.GB27593@zira.vinc17.org> <838sboar11.fsf@gnu.org> <20201030133336.GC27593@zira.vinc17.org> <83pn4zal89.fsf@gnu.org> <20201030163125.GD27593@zira.vinc17.org> Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: 8bit Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214"; logging-data="36960"; mail-complaints-to="usenet@ciao.gmane.io" User-Agent: Mutt/1.14.5+76 (bb407ec3) vl-127292 (2020-06-24) Cc: 44284@debbugs.gnu.org To: Eli Zaretskii Original-X-From: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane-mx.org@gnu.org Fri Oct 30 21:35:30 2020 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 1kYb7S-0009Ts-9i for geb-bug-gnu-emacs@m.gmane-mx.org; Fri, 30 Oct 2020 21:35:30 +0100 Original-Received: from localhost ([::1]:57392 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1kYb7R-00025q-C6 for geb-bug-gnu-emacs@m.gmane-mx.org; Fri, 30 Oct 2020 16:35:29 -0400 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]:55140) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1kYb70-00024n-Jj for bug-gnu-emacs@gnu.org; Fri, 30 Oct 2020 16:35:02 -0400 Original-Received: from debbugs.gnu.org ([209.51.188.43]:48325) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1kYb70-0000h8-AC for bug-gnu-emacs@gnu.org; Fri, 30 Oct 2020 16:35:02 -0400 Original-Received: from Debian-debbugs by debbugs.gnu.org with local (Exim 4.84_2) (envelope-from ) id 1kYb70-0000dk-7E for bug-gnu-emacs@gnu.org; Fri, 30 Oct 2020 16:35:02 -0400 X-Loop: help-debbugs@gnu.org Resent-From: Vincent Lefevre Original-Sender: "Debbugs-submit" Resent-CC: bug-gnu-emacs@gnu.org Resent-Date: Fri, 30 Oct 2020 20:35:02 +0000 Resent-Message-ID: Resent-Sender: help-debbugs@gnu.org X-GNU-PR-Message: followup 44284 X-GNU-PR-Package: emacs Original-Received: via spool by 44284-submit@debbugs.gnu.org id=B44284.16040900962443 (code B ref 44284); Fri, 30 Oct 2020 20:35:02 +0000 Original-Received: (at 44284) by debbugs.gnu.org; 30 Oct 2020 20:34:56 +0000 Original-Received: from localhost ([127.0.0.1]:59871 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1kYb6t-0000dL-NE for submit@debbugs.gnu.org; Fri, 30 Oct 2020 16:34:55 -0400 Original-Received: from joooj.vinc17.net ([155.133.131.76]:56490) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1kYb6s-0000dE-NF for 44284@debbugs.gnu.org; Fri, 30 Oct 2020 16:34:55 -0400 Original-Received: from smtp-zira.vinc17.net (128.119.75.86.rev.sfr.net [86.75.119.128]) by joooj.vinc17.net (Postfix) with ESMTPSA id 68DF84D9; Fri, 30 Oct 2020 21:34:53 +0100 (CET) Original-Received: by zira.vinc17.org (Postfix, from userid 1000) id 28D5EC233E7; Fri, 30 Oct 2020 21:34:53 +0100 (CET) Content-Disposition: inline In-Reply-To: <20201030163125.GD27593@zira.vinc17.org> X-Mailer-Info: https://www.vinc17.net/mutt/ 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:192194 Archived-At: I've found the cause of this issue: with the culprit font, it is not always possible to put the text cursor on the last line in the window, either with a mouse click or with the down arrow: Emacs scrolls the text so that the cursor is at the center of the window. Why/when this occurs remains to be determined (is there some rounding involved?). When the bug does not occur with the mouse wheel, the cursor is put on the last line. But with the culprit font, I suppose that the above issue causes another scroll in the opposite direction, hence the observed behavior. -- Vincent Lefèvre - Web: 100% accessible validated (X)HTML - Blog: Work: CR INRIA - computer arithmetic / AriC project (LIP, ENS-Lyon)