From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Richard Stallman Newsgroups: gmane.emacs.devel Subject: Re: image scaling Date: Fri, 22 Feb 2008 17:57:20 -0500 Message-ID: References: <87odaam9oy.fsf@stupidchicken.com> <8563wiaskc.fsf@lola.goethe.zz> <87lk5dr3kf.fsf@stupidchicken.com> Reply-To: rms@gnu.org NNTP-Posting-Host: lo.gmane.org Content-Type: text/plain; charset=ISO-8859-15 X-Trace: ger.gmane.org 1203721354 17242 80.91.229.12 (22 Feb 2008 23:02:34 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Fri, 22 Feb 2008 23:02:34 +0000 (UTC) Cc: monnier@iro.umontreal.ca, emacs-devel@gnu.org To: Chong Yidong Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Sat Feb 23 00:02:58 2008 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 4.50) id 1JSgup-0007cG-9p for ged-emacs-devel@m.gmane.org; Sat, 23 Feb 2008 00:02:51 +0100 Original-Received: from localhost ([127.0.0.1] helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1JSguK-0001qc-0f for ged-emacs-devel@m.gmane.org; Fri, 22 Feb 2008 18:02:20 -0500 Original-Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1JSgpW-0005gY-SY for emacs-devel@gnu.org; Fri, 22 Feb 2008 17:57:22 -0500 Original-Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1JSgpV-0005ee-BP for emacs-devel@gnu.org; Fri, 22 Feb 2008 17:57:22 -0500 Original-Received: from [199.232.76.173] (helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1JSgpV-0005eG-3H for emacs-devel@gnu.org; Fri, 22 Feb 2008 17:57:21 -0500 Original-Received: from fencepost.gnu.org ([140.186.70.10]) by monty-python.gnu.org with esmtp (Exim 4.60) (envelope-from ) id 1JSgpV-0001Hm-3P for emacs-devel@gnu.org; Fri, 22 Feb 2008 17:57:21 -0500 Original-Received: from rms by fencepost.gnu.org with local (Exim 4.67) (envelope-from ) id 1JSgpU-0005Iu-85; Fri, 22 Feb 2008 17:57:20 -0500 In-reply-to: <87lk5dr3kf.fsf@stupidchicken.com> (message from Chong Yidong on Thu, 21 Feb 2008 23:57:20 -0500) X-detected-kernel: by monty-python.gnu.org: Linux 2.6, seldom 2.4 (older, 4) 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:90043 Archived-At: My main concern with outsourcing particular bits of the Emacs image functionality to external libraries (which may or may not be linked in) is how this will look at the Lisp level. The natural and convenient way is to put something in the text properties that specify scaling, etc. That makes it very easy for Lisp programs to specify scaling. But it would be a mess if we force users (Lisp coders) to perform a similar test before performing things like image rescaling---or, worse still, having such functionality quietly disappear, by functions not being defined or becoming no-ops. The tremendous advantage of using library facilities for this outweighs that disadvantage. We should not write our own "fallback" code, because that is duplication of effort. Let's use the libraries to save our time so we can make some other improvement. As for refactoring the Emacs image code, I'm not sure if there's any urgency for such a project. The code isn't elegant, but it's simple enough to understand and work on; and I don't know of any performance problem in the way Emacs handles image pixmaps. I agree it is not urgent, but it is quite desirable. We could release Emacs 23 without doing this, but we would very much like someone to do it after that.