From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.blaine.gmane.org!not-for-mail From: Spencer Baugh Newsgroups: gmane.emacs.help Subject: Re: Make scroll-{up, down} move point to {start, end} of newly visible text Date: Wed, 16 Aug 2023 12:20:23 -0400 Message-ID: References: <83mszb0w9l.fsf@gnu.org> Mime-Version: 1.0 Content-Type: text/plain Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214"; logging-data="21239"; mail-complaints-to="usenet@ciao.gmane.io" User-Agent: Gnus/5.13 (Gnus v5.13) To: help-gnu-emacs@gnu.org Cancel-Lock: sha1:hfc7f89B2qmXi/J/jc3/QlHk8WA= Original-X-From: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane-mx.org@gnu.org Wed Aug 16 18:21:16 2023 Return-path: Envelope-to: geh-help-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 1qWJGm-0005JV-68 for geh-help-gnu-emacs@m.gmane-mx.org; Wed, 16 Aug 2023 18:21:16 +0200 Original-Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1qWJGA-0001c4-6a; Wed, 16 Aug 2023 12:20:38 -0400 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qWJG8-0001bt-Hq for help-gnu-emacs@gnu.org; Wed, 16 Aug 2023 12:20:36 -0400 Original-Received: from ciao.gmane.io ([116.202.254.214]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qWJG6-0004ey-DH for help-gnu-emacs@gnu.org; Wed, 16 Aug 2023 12:20:36 -0400 Original-Received: from list by ciao.gmane.io with local (Exim 4.92) (envelope-from ) id 1qWJG3-0004Q1-TN for help-gnu-emacs@gnu.org; Wed, 16 Aug 2023 18:20:31 +0200 X-Injected-Via-Gmane: http://gmane.org/ Received-SPF: pass client-ip=116.202.254.214; envelope-from=geh-help-gnu-emacs@m.gmane-mx.org; helo=ciao.gmane.io X-Spam_score_int: -15 X-Spam_score: -1.6 X-Spam_bar: - X-Spam_report: (-1.6 / 5.0 requ) BAYES_00=-1.9, HEADER_FROM_DIFFERENT_DOMAINS=0.25, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=no autolearn_force=no X-Spam_action: no action X-BeenThere: help-gnu-emacs@gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Users list for the GNU Emacs text editor List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane-mx.org@gnu.org Original-Sender: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane-mx.org@gnu.org Xref: news.gmane.io gmane.emacs.help:144834 Archived-At: Eli Zaretskii writes: >> From: Spencer Baugh >> Date: Mon, 31 Jul 2023 16:18:15 -0400 >> >> >> After I use scroll-up or scroll-down, I want to start reading the new >> text on the screen. But it's easy to lose track of where the new text >> start, especially with larger values of next-screen-context-lines. >> >> So, I would like scrolling to move point to the division between old and >> new text. Then the location of the cursor will help me keep track of >> which text is new and which text is old. > > I don't understand, because what you want happens here by default: > scrolling always puts at the top of the window the first line of those > which constitute next-screen-context-lines. So, for example, if you > have next-screen-context-lines set to 5, C-v will put the 5th line > from the window's bottom at the top screen line. > > If by "new text start" you mean the first line that was not visible in > the window before C-v, then set scroll-margin to the value of > next-screen-context-lines, and then Emacs will put point at that first > new line. > > Is that what you want? After using it for a bit, I ended up deciding that the other effects of scroll-margin were too annoying, so I turned it off again. (scroll-margin interacts poorly with C-M-l for example, because C-M-l puts the start of the function at the top of the screen, but actually moving point to the start of the function then causes annoying scrolling.) So I still want some other way to achieve this behavior which doesn't change scroll-margin. I thought about what behavior I want, exactly, and I think it's this: when point is off-screen after scroll-up, we should first try to move point to "window-end before we scrolled", and only if that position is also off-screen should we move point to window-start. (Currently we unconditionally move point to window-start) Like this: (defun my-scroll-up-command (&optional arg) (interactive "^P") (move-to-window-line -1) (scroll-up-command arg)) (defun my-scroll-down-command (&optional arg) (interactive "^P") (move-to-window-line 0) (scroll-down-command arg)) except of course this implementation moves point even if it's not necessary. Does this seem like a reasonable feature to add to the scrolling code?