From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.ciao.gmane.io!not-for-mail From: Eli Zaretskii Newsgroups: gmane.emacs.devel Subject: Re: Emacs canvas support Date: Thu, 30 Apr 2020 16:33:36 +0300 Message-ID: <834kt1xfm7.fsf@gnu.org> References: <83o8raziis.fsf@gnu.org> <877dxy1smz.fsf@yahoo.com> <87o8rae0ao.fsf@randomsample> <83lfmexmfp.fsf@gnu.org> <20200429171619.GB20842@tuxteam.de> <83imhixkva.fsf@gnu.org> <20200429185128.GA27164@tuxteam.de> <83ees6xggr.fsf@gnu.org> <20200429190854.GC27164@tuxteam.de> <83a72uxffz.fsf@gnu.org> <20200429195930.GA29703@tuxteam.de> Injection-Info: ciao.gmane.io; posting-host="ciao.gmane.io:159.69.161.202"; logging-data="6104"; mail-complaints-to="usenet@ciao.gmane.io" Cc: emacs-devel@gnu.org To: tomas@tuxteam.de Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Thu Apr 30 15:38:42 2020 Return-path: Envelope-to: ged-emacs-devel@m.gmane-mx.org Original-Received: from lists.gnu.org ([209.51.188.17]) by ciao.gmane.io with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1jU9Oi-0001SF-Gp for ged-emacs-devel@m.gmane-mx.org; Thu, 30 Apr 2020 15:38:40 +0200 Original-Received: from localhost ([::1]:38302 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jU9Oh-0001s1-Fc for ged-emacs-devel@m.gmane-mx.org; Thu, 30 Apr 2020 09:38:39 -0400 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]:47614) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jU9K3-0007Tk-R5 for emacs-devel@gnu.org; Thu, 30 Apr 2020 09:37:39 -0400 Original-Received: from fencepost.gnu.org ([2001:470:142:3::e]:48774) by eggs.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jU9K3-0006F6-CO; Thu, 30 Apr 2020 09:33:51 -0400 Original-Received: from [176.228.60.248] (port=4433 helo=home-c4e4a596f7) by fencepost.gnu.org with esmtpsa (TLS1.2:RSA_AES_256_CBC_SHA1:256) (Exim 4.82) (envelope-from ) id 1jU9K2-0000eD-Q5; Thu, 30 Apr 2020 09:33:51 -0400 In-Reply-To: <20200429195930.GA29703@tuxteam.de> (tomas@tuxteam.de) X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.23 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-mx.org@gnu.org Original-Sender: "Emacs-devel" Xref: news.gmane.io gmane.emacs.devel:248232 Archived-At: > Date: Wed, 29 Apr 2020 21:59:30 +0200 > From: tomas@tuxteam.de > Cc: emacs-devel@gnu.org > > > The current display engine works by screen lines, so if we want to > > keep it, we must use the existing framework. > > Now imagine there's a (graphical) line going from (text) display > line 3 to 7. You are not implying that we have to segment that > into four chunks, one per text line? That's one way, but it's ugly and complicated. > > > When a portion of a > > window is exposed, we redraw all the glyphs in the exposed area(s), > > and we find the glyphs that need to be redrawn by comparing their > > coordinates with those of the exposed rectangle(s). > > ... but rather that we intersect the exposed area(s) with each [1] > of the graphical objects and redraw that (be it before or after the > text)? Yes, but we examine what you call "objects" by screen lines. > [1] conceptually; in reality we'll need some index structure > to avoid looking at most of the graphical objects. Quad- > trees, whatever. We don't use them now. A typical window is not large enough to make that a worthy complication.