From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Eli Zaretskii Newsgroups: gmane.emacs.devel Subject: Re: Emacs and Gnome Canvas Date: Fri, 16 Jul 2010 12:52:12 +0300 Message-ID: <83iq4fg3eb.fsf@gnu.org> References: <4C3CD120.4040905@swipnet.se> <5A91499A-0470-43FD-9F48-560CEAD3424C@mit.edu> <83wrsyr068.fsf@gnu.org> <83iq4hhjww.fsf@gnu.org> <87sk3lbvv0.fsf@telefonica.net> <83hbk1grnq.fsf@gnu.org> <4C3EBCDC.8050709@swipnet.se> <83d3upgmwj.fsf@gnu.org> <4C3ECB4C.6050208@swipnet.se> <83aaptgly1.fsf@gnu.org> <4C3ED4F9.4080603@swipnet.se> <83630hgi0r.fsf@gnu.org> <4C3EE8D6.3020607@swipnet.se> <8339vlgcax.fsf@gnu.org> <87fwzkbzg8.fsf@telefonica.net> <877hkwag6y.fsf@stupidchicken.com> <4C400B3C.4000203@swipnet.se> Reply-To: Eli Zaretskii NNTP-Posting-Host: lo.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE X-Trace: dough.gmane.org 1279274566 21963 80.91.229.12 (16 Jul 2010 10:02:46 GMT) X-Complaints-To: usenet@dough.gmane.org NNTP-Posting-Date: Fri, 16 Jul 2010 10:02:46 +0000 (UTC) Cc: ofv@wanadoo.es, cyd@stupidchicken.com, mituharu@math.s.chiba-u.ac.jp, emacs-devel@gnu.org To: =?ISO-8859-1?Q?Jan_Dj=E4rv?= Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Fri Jul 16 12:02:44 2010 Return-path: Envelope-to: ged-emacs-devel@m.gmane.org Original-Received: from lists.gnu.org ([199.232.76.165]) by lo.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1OZhkh-0007SN-3E for ged-emacs-devel@m.gmane.org; Fri, 16 Jul 2010 12:02:43 +0200 Original-Received: from localhost ([127.0.0.1]:46516 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1OZhkg-00067E-9W for ged-emacs-devel@m.gmane.org; Fri, 16 Jul 2010 06:02:42 -0400 Original-Received: from [140.186.70.92] (port=47427 helo=eggs.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1OZhkS-00060T-WF for emacs-devel@gnu.org; Fri, 16 Jul 2010 06:02:31 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.69) (envelope-from ) id 1OZhdF-0005SL-7J for emacs-devel@gnu.org; Fri, 16 Jul 2010 05:55:02 -0400 Original-Received: from mtaout21.012.net.il ([80.179.55.169]:47925) by eggs.gnu.org with esmtp (Exim 4.69) (envelope-from ) id 1OZhdF-0005S6-05 for emacs-devel@gnu.org; Fri, 16 Jul 2010 05:55:01 -0400 Original-Received: from conversion-daemon.a-mtaout21.012.net.il by a-mtaout21.012.net.il (HyperSendmail v2007.08) id <0L5N00H00A1SFZ00@a-mtaout21.012.net.il> for emacs-devel@gnu.org; Fri, 16 Jul 2010 12:54:09 +0300 (IDT) Original-Received: from HOME-C4E4A596F7 ([77.127.120.144]) by a-mtaout21.012.net.il (HyperSendmail v2007.08) with ESMTPA id <0L5N00E19A68WR90@a-mtaout21.012.net.il>; Fri, 16 Jul 2010 12:54:09 +0300 (IDT) In-reply-to: <4C400B3C.4000203@swipnet.se> X-012-Sender: halo1@inter.net.il X-detected-operating-system: by eggs.gnu.org: Solaris 10 (beta) X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: "Emacs development discussions." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Original-Sender: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Errors-To: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Xref: news.gmane.org gmane.emacs.devel:127421 Archived-At: > Date: Fri, 16 Jul 2010 09:33:16 +0200 > From: Jan Dj=E4rv > Cc: Chong Yidong , emacs-devel@gnu.org, > =D3scar Fuentes >=20 > > 2. Restrict the actual drawings to those in response to exposu= re > > events. This is the standard way in GTK+ and Cocoa. That = would > > make double-buffering straightforward in GTK+ builds. >=20 > This is good, but can the current redisplay engine really update ju= st a part=20 > of the display area? It depends on what you mean by "redisplay engine" in this context. The high-level, platform-independent part of the display engine has its own ideas regarding which parts need to be redrawn, and I won't recommend modifying that. But this part of the engine does not draw anything. It just produces an interim _representation_ of the desire= d screen contents, stored as a "glyph matrix" structure. It is then th= e job of the terminal-specific back-end to actually draw the screen based on the desired matrix. What the back-end does is entirely up t= o it, provided that it keeps a very simple contract: that after it's done, the contents of the screen is 100% according to the desired matrix. Btw, I don't think I understand what Mitsuharu says in this Item #2. Surely, we cannot "restrict the actual drawings to those in response to exposure events"? A completely exposed window does need to be redrawn if the buffer text changes, right? What am I missing?