From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Andreas Politz Newsgroups: gmane.emacs.devel Subject: Re: Displaying scrollable images in a grid-layout Date: Tue, 14 Apr 2015 21:29:04 +0200 Message-ID: <87zj6a33sv.fsf@hochschule-trier.de> References: <87pp785u5a.fsf@hochschule-trier.de> <83r3rocbzr.fsf@gnu.org> <87bnirzur7.fsf@hochschule-trier.de> <83egnndb93.fsf@gnu.org> <83sic2bvx8.fsf@gnu.org> NNTP-Posting-Host: plane.gmane.org Mime-Version: 1.0 Content-Type: text/plain X-Trace: ger.gmane.org 1429065307 2016 80.91.229.3 (15 Apr 2015 02:35:07 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Wed, 15 Apr 2015 02:35:07 +0000 (UTC) Cc: emacs-devel@gnu.org To: Eli Zaretskii Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Wed Apr 15 04:34:57 2015 Return-path: Envelope-to: ged-emacs-devel@m.gmane.org Original-Received: from lists.gnu.org ([208.118.235.17]) by plane.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1YiDAF-0005RX-DA for ged-emacs-devel@m.gmane.org; Wed, 15 Apr 2015 04:34:55 +0200 Original-Received: from localhost ([::1]:58541 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YiDAE-0003U5-JN for ged-emacs-devel@m.gmane.org; Tue, 14 Apr 2015 22:34:54 -0400 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:59015) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Yi6YS-0000jh-63 for emacs-devel@gnu.org; Tue, 14 Apr 2015 15:31:29 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Yi6YR-0000i3-62 for emacs-devel@gnu.org; Tue, 14 Apr 2015 15:31:28 -0400 Original-Received: from gateway-a.fh-trier.de ([143.93.54.181]:42686) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Yi6YN-0000gJ-5G; Tue, 14 Apr 2015 15:31:23 -0400 X-Virus-Scanned: by Amavisd-new + McAfee uvscan + ClamAV [Rechenzentrum Hochschule Trier] Original-Received: from luca (dslb-088-067-095-051.088.067.pools.vodafone-ip.de [88.67.95.51]) (using TLSv1 with cipher DHE-RSA-AES128-SHA (128/128 bits)) (No client certificate requested) (Authenticated sender: politza) by gateway-a.fh-trier.de (Postfix) with ESMTPSA id B03532163E; Tue, 14 Apr 2015 21:31:13 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha1; c=simple/simple; d=hochschule-trier.de; s=default; t=1429039873; bh=RVcmqmqjXntohqdVwFvDwKOkj7M=; h=From:To:Cc:Subject:In-Reply-To:Date:References:Message-ID: MIME-Version:Content-Type; b=BStu2ZcjBlLZXbMkLPhZKnsPruANEwfzV5ZdDJzSa4DLkFf8QuNgYHstcULxYQXV0 M9192FSXRFe5uuHxislBRvPyPrsIdxPnd/ptXVmq9uItInN0T2YOvibz5X3XMXegwh IUyKjYKG7Y2oBfLpSYTOy5w5qrQ3/fhCABzbXb5g= Original-Received: from politza by luca with local (Exim 4.80) (envelope-from ) id 1Yi6YC-0004sL-Vx; Tue, 14 Apr 2015 21:31:12 +0200 In-Reply-To: <83sic2bvx8.fsf@gnu.org> (Eli Zaretskii's message of "Tue, 14 Apr 2015 17:56:35 +0300") User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/25.0.50 (gnu/linux) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.6.x X-Received-From: 143.93.54.181 X-Mailman-Approved-At: Tue, 14 Apr 2015 22:34:52 -0400 X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: "Emacs development discussions." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Original-Sender: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Xref: news.gmane.org gmane.emacs.devel:185434 Archived-At: Eli Zaretskii writes: >> Try this: >> >> (defun show-data-dir-images (&optional ncolumns) >> [...] > After running this function, this works for me: > > (set-window-vscroll nil N t) > > as long as (a) point is not on the first screen line shown in the > window, and (b) N is no more than 24, which AFAICS is the pixel size > of the small images created by the above function. Yes but the whole point is to display only half of an image at the top. This recipe is not ideal. In the real application I would have 2 images (pages of a PDF) side by side, filling e.g 3/4 of the windows vertical space. Below these images are another 2 which are only 1/4-way visible. Now I want to scroll these 4 images up by let's say the equivalent of next-screen-context-lines in pixels. Would this be a feature supported by Emacs ? >> (setq-local scroll-step 1) >> (set-window-vscroll nil 10) => Scrolls, but: >> >> Redisplay performance (or something else) greatly suffers,[...] > > I don't see this performance hit. [...] I am not able to reproduce it either just now... > The other points I made in my previous message and today still hold: > there are limits to what Emacs will currently let you do with > window-vscroll, mainly due to 2 factors: > > . the basic desire embedded in redisplay to avoid showing partial > lines, unless they are unavoidable > > . the automatic scrolling when point goes off the window > > Let me know if you need further help or have additional > questions/issues about this. Thank you. -ap