From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Alan Mackenzie Newsgroups: gmane.emacs.devel Subject: Re: Unfreezing the display during auto-repeated scrolling. Simpler approach. Date: Sun, 23 Nov 2014 22:04:41 +0000 Message-ID: <20141123220441.GA3628@acm.acm> References: <20141029212525.GD2953@acm.acm> <20141030220919.GB2721@acm.acm> <83oasszn9e.fsf@gnu.org> <20141121154420.GA24582@acm.acm> <87vbm6z1lc.fsf@thinkpad-t440p.tsdh.org> <20141123104038.GA3542@acm.acm> <87egstaehk.fsf@thinkpad-t440p.tsdh.org> NNTP-Posting-Host: plane.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Trace: ger.gmane.org 1416780348 23025 80.91.229.3 (23 Nov 2014 22:05:48 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Sun, 23 Nov 2014 22:05:48 +0000 (UTC) To: Stefan Monnier , Eli Zaretskii , emacs-devel@gnu.org Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Sun Nov 23 23:05:40 2014 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 1XsfHn-0003qp-NO for ged-emacs-devel@m.gmane.org; Sun, 23 Nov 2014 23:05:39 +0100 Original-Received: from localhost ([::1]:50131 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XsfHn-00040m-9e for ged-emacs-devel@m.gmane.org; Sun, 23 Nov 2014 17:05:39 -0500 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:58886) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XsfHR-00040a-48 for emacs-devel@gnu.org; Sun, 23 Nov 2014 17:05:22 -0500 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1XsfHL-0001fX-Cy for emacs-devel@gnu.org; Sun, 23 Nov 2014 17:05:17 -0500 Original-Received: from colin.muc.de ([193.149.48.1]:60368 helo=mail.muc.de) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XsfHL-0001fK-3s for emacs-devel@gnu.org; Sun, 23 Nov 2014 17:05:11 -0500 Original-Received: (qmail 57367 invoked by uid 3782); 23 Nov 2014 22:05:09 -0000 Original-Received: from acm.muc.de (pD9519EFE.dip0.t-ipconnect.de [217.81.158.254]) by colin.muc.de (tmda-ofmipd) with ESMTP; Sun, 23 Nov 2014 23:05:08 +0100 Original-Received: (qmail 3737 invoked by uid 1000); 23 Nov 2014 22:04:41 -0000 Content-Disposition: inline In-Reply-To: <87egstaehk.fsf@thinkpad-t440p.tsdh.org> User-Agent: Mutt/1.5.21 (2010-09-15) X-Delivery-Agent: TMDA/1.1.12 (Macallan) X-Primary-Address: acm@muc.de X-detected-operating-system: by eggs.gnu.org: FreeBSD 8.x X-Received-From: 193.149.48.1 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:178130 Archived-At: Hello, Tassilo. On Sun, Nov 23, 2014 at 08:44:39PM +0100, Tassilo Horn wrote: > Alan Mackenzie writes: > Hi Alan, > > To see the effect, make your window as large as possible (mine was 66 > > lines deep) and try with a file like .../src/xdisp.c. Toggle > > font-lock-mode off and on between each try. If you still don't see any > > difference, then your machine is powerful enough not to need the feature. > Oh, indeed. My machine is pretty fast at least for a laptop, but when > holding C-v the display freezes very quickly as you say. With > `use-default-face-for-fast-scrolling' I don't get such freezes, so this > looks like a very good feature to me (2nd best after "make the display > engine faster"). It's CC Mode's fontification, rather than the display engine, which is slow here. But in a large window, even Emacs Lisp Mode can only just keep up: On my 2.6 GHz Athlon II, with a 66 line window, and the keyboard auto-repeating every 0.024s, fontifying and displaying a screen took ~0.018s. There's not a lot of spare time for fancier fontification. > But still I think the variable's name is a bit misleading. I expected > to see the text that scrolls by black on white, i.e., using the default > face similar to having `jit-lock-defer-time' set to some non-nil value. > But instead the text that scrolls by and is visible is fontified using > the normal font-lock faces. :-). I had quite some trouble coming up with a name for the option. Something like `assume-default-face-for-nondisplayed-screens-in-scrolling' would be more accurate, but a bit of a mouthful. If you've any suggestions for improvement, post them! > Bye, > Tassilo -- Alan Mackenzie (Nuremberg, Germany).