From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!.POSTED!not-for-mail From: Yuri Khan Newsgroups: gmane.emacs.help Subject: Re: Scrolling jumpy when line-spacing > 0 Date: Sat, 22 Apr 2017 02:30:25 +0700 Message-ID: References: <83inlxako6.fsf@gnu.org> <838tmta8sy.fsf@gnu.org> NNTP-Posting-Host: blaine.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable X-Trace: blaine.gmane.org 1492810297 1137 195.159.176.226 (21 Apr 2017 21:31:37 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Fri, 21 Apr 2017 21:31:37 +0000 (UTC) Cc: "help-gnu-emacs@gnu.org" To: Eli Zaretskii Original-X-From: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane.org@gnu.org Fri Apr 21 23:31:34 2017 Return-path: Envelope-to: geh-help-gnu-emacs@m.gmane.org Original-Received: from lists.gnu.org ([208.118.235.17]) by blaine.gmane.org with esmtp (Exim 4.84_2) (envelope-from ) id 1d1g9N-00005D-PR for geh-help-gnu-emacs@m.gmane.org; Fri, 21 Apr 2017 23:31:33 +0200 Original-Received: from localhost ([::1]:33265 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1d1g9O-0008GB-DU for geh-help-gnu-emacs@m.gmane.org; Fri, 21 Apr 2017 17:31:34 -0400 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:54590) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1d1eGX-0000cq-P3 for help-gnu-emacs@gnu.org; Fri, 21 Apr 2017 15:30:50 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1d1eGW-0007Hz-Va for help-gnu-emacs@gnu.org; Fri, 21 Apr 2017 15:30:49 -0400 Original-Received: from mail-wm0-x230.google.com ([2a00:1450:400c:c09::230]:38522) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1d1eGV-0007HV-CY; Fri, 21 Apr 2017 15:30:47 -0400 Original-Received: by mail-wm0-x230.google.com with SMTP id r190so24782109wme.1; Fri, 21 Apr 2017 12:30:47 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:sender:in-reply-to:references:from:date:message-id :subject:to:cc:content-transfer-encoding; bh=ze/Mq50Gm1rgzmRlit4KoVRTMkEdfnS8Y0aeN6Hi7nA=; b=Xvo7GhnYOCCVWJP/AS0piM+nnX3ZD6miB7HTkIGd4o1mpcPO1ffNDiiC3yndYph/nh OgeuGYxn6KdxtWmw2CyM9K5VYE3KGbNjHFVH9I0EOzMclMCOvppn7+Sac9DLvvlk3Zo0 vstTRz3wZbd+DZqRSNsnOxA8m1maU7QelWqZD/MM9JvxK/rcECFiwfWxdhru0SQ0n5JO 89oTbQfOUf1yo6gYyJOLDGUTXalsI9Lsr99IWI/mutN99wU8zAny/jgf4+rDPdVN7xRN VHXfhkAnyDcnUSSl/7MlbPaj8u1U3BMZFGOns7djpHXNlsrb3vzop987UPTfruRVkonN i2aQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:sender:in-reply-to:references:from :date:message-id:subject:to:cc:content-transfer-encoding; bh=ze/Mq50Gm1rgzmRlit4KoVRTMkEdfnS8Y0aeN6Hi7nA=; b=TIlrxXPh5f8S9BSnr1yGOTBRDglqYnryolITACzdB6RvDJtah5SJjFuwkpeAA7oVy6 yITJ01OTyHkk1rqfnMnwRTTzPzPn1pMQObfOfvam5hgKqf3jggExWJRk1gLI+xCKRRhT IoeL8g89dLaAVgUf1vQhZcSkZ48Ykl2myf5zwLRT+LJnJi72z0G/ea+OmbBFGhzy/6pp 4CuLGQeTpadUV96tpM33KJJl3YUGjW6pvAZv0l7wcpdZxbG5Luum5KA5MehqFLq8RujF FvGdSzF7dmecqw9JpPQyzJoxCdfvxDZHarSlZe/Nn0I8dcUlJ49B2oEGxRbitHuEPMEc sOwg== X-Gm-Message-State: AN3rC/5cA2t5X+0HvQqCKeRrzYDABcqy4v2+FsbaQKRja8M32mlFgMnp UWtS0GS/Z99Of0edgGWdE97FU/4h2no1 X-Received: by 10.28.104.195 with SMTP id d186mr171353wmc.111.1492803046014; Fri, 21 Apr 2017 12:30:46 -0700 (PDT) Original-Received: by 10.223.169.12 with HTTP; Fri, 21 Apr 2017 12:30:25 -0700 (PDT) In-Reply-To: <838tmta8sy.fsf@gnu.org> X-Google-Sender-Auth: 5dLEw4sWiQu-T0E58jtT2l_z1Z4 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 2a00:1450:400c:c09::230 X-Mailman-Approved-At: Fri, 21 Apr 2017 17:29:42 -0400 X-BeenThere: help-gnu-emacs@gnu.org X-Mailman-Version: 2.1.21 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.org@gnu.org Original-Sender: "help-gnu-emacs" Xref: news.gmane.org gmane.emacs.help:112850 Archived-At: On Sat, Apr 22, 2017 at 1:56 AM, Eli Zaretskii wrote: >> > (Why do people report bugs here, rather than with report-emacs-bug?) >> >> To check if that is indeed a bug worth reporting, or if it is already >> known, or even already fixed? > > All of these are good enough reasons to post to the bug tracker. Okay. >> As a user, I=E2=80=99d expect that additional spacing does not count tow= ard >> whether the line is considered visible. > > The Emacs display engine was designed to avoid having point in a > partially visible line, for whatever reasons. The code which checks > for partial visibility doesn't care what is in the invisible part, > because checking for that would take non-trivial processing, and the > subtlety isn't important enough to slow down redisplay. How come Emacs 24 lets me put point in that partially fully visible line? Was something simplified between 24 and master? To me, that kind of subtlety is important. Not that important to cry regression, but important enough to wonder if I could afford the slowdown. I=E2=80=99m even mildly bothered by the fact that spacing is conceptually below its line; I=E2=80=99d find it nicer if half of it was above. >> The other special case is when the point is in the topmost visible >> line. >> [=E2=80=A6] >> I see no practical way to detect this condition without moving point. > > Doesn't posn-at-point allow you to find out whether point is in the > topmost window line? (Caveat: this could require special > consideration when there's a non-nil header-line-format in the > window.) Maybe. Maybe not. On the one hand, I do have a non-nil header-line-format at all times. (For tabbar-mode.) On the other hand, when I evaluate (posn-at-point) with point in the topmost window line, I get zero Y and ROW values. It is not immediately clear if I can rely on that. On the third hand, using motion relative to the point is immediately clear. What=E2=80=99s the downside? Is it going to be slow? Slow enough to = be noticeable at a key repeat rate of 40 Hz?