From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Eli Zaretskii Newsgroups: gmane.emacs.bugs Subject: bug#16621: 24.3.50; Periodic timer + overlays = flickering near point Date: Tue, 04 Feb 2014 05:48:53 +0200 Message-ID: <83eh3j35cq.fsf@gnu.org> References: <87r47m72ft.fsf@yandex.ru> <838utt4gff.fsf@gnu.org> <52F051D2.9020404@yandex.ru> Reply-To: Eli Zaretskii NNTP-Posting-Host: plane.gmane.org X-Trace: ger.gmane.org 1391485811 22515 80.91.229.3 (4 Feb 2014 03:50:11 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Tue, 4 Feb 2014 03:50:11 +0000 (UTC) Cc: 16621@debbugs.gnu.org To: Dmitry Gutov Original-X-From: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane.org@gnu.org Tue Feb 04 04:50:17 2014 Return-path: Envelope-to: geb-bug-gnu-emacs@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 1WAX1c-0005sn-Fx for geb-bug-gnu-emacs@m.gmane.org; Tue, 04 Feb 2014 04:50:16 +0100 Original-Received: from localhost ([::1]:50582 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1WAX1b-00022m-PR for geb-bug-gnu-emacs@m.gmane.org; Mon, 03 Feb 2014 22:50:15 -0500 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:43580) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1WAX1T-00020H-Nd for bug-gnu-emacs@gnu.org; Mon, 03 Feb 2014 22:50:12 -0500 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1WAX1O-0002HR-CU for bug-gnu-emacs@gnu.org; Mon, 03 Feb 2014 22:50:07 -0500 Original-Received: from debbugs.gnu.org ([140.186.70.43]:34583) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1WAX1O-0002Gz-98 for bug-gnu-emacs@gnu.org; Mon, 03 Feb 2014 22:50:02 -0500 Original-Received: from Debian-debbugs by debbugs.gnu.org with local (Exim 4.80) (envelope-from ) id 1WAX1O-0004rm-2j for bug-gnu-emacs@gnu.org; Mon, 03 Feb 2014 22:50:02 -0500 X-Loop: help-debbugs@gnu.org Resent-From: Eli Zaretskii Original-Sender: "Debbugs-submit" Resent-CC: bug-gnu-emacs@gnu.org Resent-Date: Tue, 04 Feb 2014 03:50:02 +0000 Resent-Message-ID: Resent-Sender: help-debbugs@gnu.org X-GNU-PR-Message: followup 16621 X-GNU-PR-Package: emacs X-GNU-PR-Keywords: Original-Received: via spool by 16621-submit@debbugs.gnu.org id=B16621.139148574618636 (code B ref 16621); Tue, 04 Feb 2014 03:50:02 +0000 Original-Received: (at 16621) by debbugs.gnu.org; 4 Feb 2014 03:49:06 +0000 Original-Received: from localhost ([127.0.0.1]:48602 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.80) (envelope-from ) id 1WAX0T-0004qW-VD for submit@debbugs.gnu.org; Mon, 03 Feb 2014 22:49:06 -0500 Original-Received: from mtaout21.012.net.il ([80.179.55.169]:39552) by debbugs.gnu.org with esmtp (Exim 4.80) (envelope-from ) id 1WAX0R-0004qN-UG for 16621@debbugs.gnu.org; Mon, 03 Feb 2014 22:49:05 -0500 Original-Received: from conversion-daemon.a-mtaout21.012.net.il by a-mtaout21.012.net.il (HyperSendmail v2007.08) id <0N0G00L00D232K00@a-mtaout21.012.net.il> for 16621@debbugs.gnu.org; Tue, 04 Feb 2014 05:49:02 +0200 (IST) Original-Received: from HOME-C4E4A596F7 ([87.69.4.28]) by a-mtaout21.012.net.il (HyperSendmail v2007.08) with ESMTPA id <0N0G00KDAD9QTU80@a-mtaout21.012.net.il>; Tue, 04 Feb 2014 05:49:02 +0200 (IST) In-reply-to: <52F051D2.9020404@yandex.ru> X-012-Sender: halo1@inter.net.il X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.15 Precedence: list X-detected-operating-system: by eggs.gnu.org: GNU/Linux 3.x X-Received-From: 140.186.70.43 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.org@gnu.org Original-Sender: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane.org@gnu.org Xref: news.gmane.org gmane.emacs.bugs:84540 Archived-At: > Date: Tue, 04 Feb 2014 04:34:58 +0200 > From: Dmitry Gutov > CC: 16621@debbugs.gnu.org, Stefan Monnier > > Isn't the fact that flickering is at all possible in this scenario, a > problem? Yes, but it is currently an unavoidable one, because this is how the code was designed and implemented to work. > Doesn't it mean that occasional flickers can still happen under > normal conditions (timers with much longer intervals, for example),just > that the probability of occurrence is smaller. If I understand you > right, all it takes is for timer to fire at just the right moment before > the screen updates. Indeed, that's true. > Some relatively low-hanging fruit has already been mentioned in the > comments Like what? If you mean the fact that we redraw the cursor when perhaps that could be avoided, someone else will have to suggest a better algorithm than doing it on every frame update. Nothing else discussed here was easy, either. > but would it be too much to expect some sort of double-buffering > used for Emacs display, eventually? You mean, outside Emacs? Yes, probably, but then this isn't an Emacs issue, and I know absolutely nothing about it. > Or is the related overhead considered too much of a cost? If you mean double buffering inside Emacs, you will have to explain why you think it will solve the problem.