From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.blaine.gmane.org!not-for-mail From: Alan Third Newsgroups: gmane.emacs.bugs Subject: bug#46556: 27.1; transparent images are displayed incorrectly if rotated Date: Wed, 17 Feb 2021 19:26:38 +0000 Message-ID: References: <86mtw4tiyg.fsf@gmail.com> <87sg5ww430.fsf@gnus.org> <83blci7hgd.fsf@gnu.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214"; logging-data="17549"; mail-complaints-to="usenet@ciao.gmane.io" Cc: larsi@gnus.org, ynyaaa@gmail.com, 46556@debbugs.gnu.org To: Eli Zaretskii Original-X-From: bug-gnu-emacs-bounces+geb-bug-gnu-emacs=m.gmane-mx.org@gnu.org Wed Feb 17 20:27:42 2021 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 1lCSU8-0004QL-Ny for geb-bug-gnu-emacs@m.gmane-mx.org; Wed, 17 Feb 2021 20:27:40 +0100 Original-Received: from localhost ([::1]:50410 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lCSU7-0003I0-Ph for geb-bug-gnu-emacs@m.gmane-mx.org; Wed, 17 Feb 2021 14:27:39 -0500 Original-Received: from eggs.gnu.org ([2001:470:142:3::10]:47450) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lCSTW-0002vw-7i for bug-gnu-emacs@gnu.org; Wed, 17 Feb 2021 14:27:02 -0500 Original-Received: from debbugs.gnu.org ([209.51.188.43]:33510) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1lCSTV-0008Qv-W1 for bug-gnu-emacs@gnu.org; Wed, 17 Feb 2021 14:27:02 -0500 Original-Received: from Debian-debbugs by debbugs.gnu.org with local (Exim 4.84_2) (envelope-from ) id 1lCSTV-0004Op-R0 for bug-gnu-emacs@gnu.org; Wed, 17 Feb 2021 14:27:01 -0500 X-Loop: help-debbugs@gnu.org Resent-From: Alan Third Original-Sender: "Debbugs-submit" Resent-CC: bug-gnu-emacs@gnu.org Resent-Date: Wed, 17 Feb 2021 19:27:01 +0000 Resent-Message-ID: Resent-Sender: help-debbugs@gnu.org X-GNU-PR-Message: followup 46556 X-GNU-PR-Package: emacs X-GNU-PR-Keywords: moreinfo Original-Received: via spool by 46556-submit@debbugs.gnu.org id=B46556.161359001016894 (code B ref 46556); Wed, 17 Feb 2021 19:27:01 +0000 Original-Received: (at 46556) by debbugs.gnu.org; 17 Feb 2021 19:26:50 +0000 Original-Received: from localhost ([127.0.0.1]:45056 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1lCSTJ-0004OP-JN for submit@debbugs.gnu.org; Wed, 17 Feb 2021 14:26:49 -0500 Original-Received: from outbound.soverin.net ([116.202.65.218]:41821) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1lCSTH-0004OC-Mn for 46556@debbugs.gnu.org; Wed, 17 Feb 2021 14:26:48 -0500 Original-Received: from smtp.soverin.net (unknown [10.10.3.24]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by outbound.soverin.net (Postfix) with ESMTPS id 009D56013B; Wed, 17 Feb 2021 19:26:41 +0000 (UTC) Original-Received: from smtp.soverin.net (smtp.soverin.net [159.69.232.138]) by soverin.net DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=idiocy.org; s=soverin; t=1613590001; bh=0T8tszcNAu2shZOVQGa9VqxeCJSygyQ5r2ImITixDEE=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=NUqCbiqdky1AUqRu6vM7sGngWCHX855CjjvYG6eOPuN9wRzOYAgyaP+ZuPgFg4jP3 0h0PfIrwXgKaKnFlh2JcEhnHTfZPg4nUNCVRd4qlgnZ8sNYyjTT3XsacEIZliABpnM svw38u58c3KiemQFYo/0ycaXEaQ60JAdsvXlhyrzDIF773DD7xy54WttkIOoQbGZck SySofebepNOwt//ej1XATYPEMNmmQbDY89qCKxvqn/AF6hkKxnpGtI+UjFH7zJh5/4 GTiE5tdvk6c2attbnQGp6tmqok3002CoWZYzkaP7BAv0lhhXoLiKYe7jUUQx9RP9Ji nqffiKlG5psyA== Original-Received: by breton.holly.idiocy.org (Postfix, from userid 501) id C4869202A7FABB; Wed, 17 Feb 2021 19:26:38 +0000 (GMT) Mail-Followup-To: Alan Third , Eli Zaretskii , larsi@gnus.org, ynyaaa@gmail.com, 46556@debbugs.gnu.org Content-Disposition: inline In-Reply-To: <83blci7hgd.fsf@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:200214 Archived-At: On Wed, Feb 17, 2021 at 07:05:38PM +0200, Eli Zaretskii wrote: > > Date: Tue, 16 Feb 2021 21:24:24 +0000 > > From: Alan Third > > Cc: ynyaaa@gmail.com, 46556@debbugs.gnu.org > > > > > Would it be possible for you to test with Emacs 28 and see whether the > > > problem you report (on Windows) is still present there? > > > > It does sound like something must be going wrong on Windows. > > Unfortunately I don't know what that could be because, as I said on > > the other bug report, NS and Windows use the same rotation logic, and > > NS is fine, so it must be when it comes to actually drawing that the > > problem manifests. > > I've now stepped through the code which implements rotation, and I see > nothing wrong with the results. The pixel coordinates of the rotated > square are exact and accurate, without any roundoff that I could spot. > Each square starts exactly 50+8 = 58 pixels after the previous one (8 > pixels are taken by the SPC character between the squares), and ends > exactly 50 pixels after it starts. > > So I have no idea why the one-pixel shift happens. Of course, I don't > really understand what that code does (although I hacked it quite > extensively), so maybe someone who really understands that stuff could > take a look and tell what's wrong there. Can either you or the OP provide a screenshot? It's not entirely clear to me what's happening. It sounds like some of the behaviour of this bug would be explained by the mask not being rotated with the image, but other bits of the description don't seem to match that. The other bug with the single pixel white line sounds more like an off-by-one in SVG production, but you'd see that in every image, so it's probably not that. -- Alan Third