From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.blaine.gmane.org!not-for-mail From: Eli Zaretskii Newsgroups: gmane.emacs.bugs Subject: bug#42307: Feature request: Visual block attribute for overlays Date: Tue, 14 Jul 2020 20:10:31 +0300 Message-ID: <835zaqm394.fsf@gnu.org> References: <83k0z6n7w6.fsf@gnu.org> <83eepem9im.fsf@gnu.org> <837dv6m4xm.fsf@gnu.org> Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214"; logging-data="10443"; mail-complaints-to="usenet@ciao.gmane.io" Cc: 42307@debbugs.gnu.org To: Gregory Heytings Original-X-From: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane-mx.org@gnu.org Tue Jul 14 19:11:10 2020 Return-path: Envelope-to: geb-bug-gnu-emacs@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 1jvOSU-0002cl-El for geb-bug-gnu-emacs@m.gmane-mx.org; Tue, 14 Jul 2020 19:11:10 +0200 Original-Received: from localhost ([::1]:39720 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jvOST-0007Jk-FI for geb-bug-gnu-emacs@m.gmane-mx.org; Tue, 14 Jul 2020 13:11:09 -0400 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]:57370) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1jvOSM-0007JV-Qd for bug-gnu-emacs@gnu.org; Tue, 14 Jul 2020 13:11:02 -0400 Original-Received: from debbugs.gnu.org ([209.51.188.43]:39899) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1jvOSM-0003Nz-Gj for bug-gnu-emacs@gnu.org; Tue, 14 Jul 2020 13:11:02 -0400 Original-Received: from Debian-debbugs by debbugs.gnu.org with local (Exim 4.84_2) (envelope-from ) id 1jvOSM-0003xT-9G for bug-gnu-emacs@gnu.org; Tue, 14 Jul 2020 13:11:02 -0400 X-Loop: help-debbugs@gnu.org Resent-From: Eli Zaretskii Original-Sender: "Debbugs-submit" Resent-CC: bug-gnu-emacs@gnu.org Resent-Date: Tue, 14 Jul 2020 17:11:02 +0000 Resent-Message-ID: Resent-Sender: help-debbugs@gnu.org X-GNU-PR-Message: followup 42307 X-GNU-PR-Package: emacs Original-Received: via spool by 42307-submit@debbugs.gnu.org id=B42307.159474665515202 (code B ref 42307); Tue, 14 Jul 2020 17:11:02 +0000 Original-Received: (at 42307) by debbugs.gnu.org; 14 Jul 2020 17:10:55 +0000 Original-Received: from localhost ([127.0.0.1]:51445 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1jvOSE-0003x6-M2 for submit@debbugs.gnu.org; Tue, 14 Jul 2020 13:10:55 -0400 Original-Received: from eggs.gnu.org ([209.51.188.92]:43424) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1jvOS0-0003we-Rj for 42307@debbugs.gnu.org; Tue, 14 Jul 2020 13:10:53 -0400 Original-Received: from fencepost.gnu.org ([2001:470:142:3::e]:35293) by eggs.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jvORv-0003Dz-Kp; Tue, 14 Jul 2020 13:10:35 -0400 Original-Received: from [176.228.60.248] (port=3659 helo=home-c4e4a596f7) by fencepost.gnu.org with esmtpsa (TLS1.2:RSA_AES_256_CBC_SHA1:256) (Exim 4.82) (envelope-from ) id 1jvORu-00058V-RW; Tue, 14 Jul 2020 13:10:35 -0400 In-Reply-To: (bug-gnu-emacs@gnu.org) X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.18 Precedence: list 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-mx.org@gnu.org Original-Sender: "bug-gnu-emacs" Xref: news.gmane.io gmane.emacs.bugs:182999 Archived-At: > Date: Tue, 14 Jul 2020 17:01:43 +0000 > From: Gregory Heytings via "Bug reports for GNU Emacs, > the Swiss army knife of text editors" > > In fact, I'm not entirerly sure that explaining (or implementing) that > behavior with regexpes or character is the best thing to do. It's a > matter of visual representation. Perhaps the following explanation is > clearer (or more precise): draw the overlay with :extend t, and remove > pixel columns on the left and on the right that are displayed in the same > way as a whitespace character would have been displayed. Well, it's not that simple. For starters, there's no "pixel columns" in the display engine, at least not on GUI frames. More to the point, I think the feature you requested will be not very simple to implement, because it requires the display code to do look-ahead: when it lays out leading whitespace, it should consider characters after that. That calls for some complications, because the display code basically inspects characters one by one and makes (almost) all the decisions on the fly. So someone will have fun implementing this. Patches welcome.