From mboxrd@z Thu Jan 1 00:00:00 1970 Path: main.gmane.org!not-for-mail From: David Kastrup Newsgroups: gmane.emacs.devel Subject: Re: Several suggestions for image support Date: 23 Apr 2004 01:02:50 +0200 Sender: emacs-devel-bounces+emacs-devel=quimby.gnus.org@gnu.org Message-ID: References: NNTP-Posting-Host: deer.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Trace: sea.gmane.org 1082675275 3577 80.91.224.253 (22 Apr 2004 23:07:55 GMT) X-Complaints-To: usenet@sea.gmane.org NNTP-Posting-Date: Thu, 22 Apr 2004 23:07:55 +0000 (UTC) Cc: rms@gnu.org, emacs-devel@gnu.org Original-X-From: emacs-devel-bounces+emacs-devel=quimby.gnus.org@gnu.org Fri Apr 23 01:07:48 2004 Return-path: Original-Received: from quimby.gnus.org ([80.91.224.244]) by deer.gmane.org with esmtp (Exim 3.35 #1 (Debian)) id 1BGnIK-0005Ye-00 for ; Fri, 23 Apr 2004 01:07:48 +0200 Original-Received: from monty-python.gnu.org ([199.232.76.173]) by quimby.gnus.org with esmtp (Exim 3.35 #1 (Debian)) id 1BGnIJ-0000aX-00 for ; Fri, 23 Apr 2004 01:07:47 +0200 Original-Received: from localhost ([127.0.0.1] helo=monty-python.gnu.org) by monty-python.gnu.org with esmtp (Exim 4.30) id 1BGnEH-0007K7-3W for emacs-devel@quimby.gnus.org; Thu, 22 Apr 2004 19:03:37 -0400 Original-Received: from list by monty-python.gnu.org with tmda-scanned (Exim 4.30) id 1BGnEB-0007Jl-Gy for emacs-devel@gnu.org; Thu, 22 Apr 2004 19:03:31 -0400 Original-Received: from mail by monty-python.gnu.org with spam-scanned (Exim 4.30) id 1BGnDf-0007Ee-2p for emacs-devel@gnu.org; Thu, 22 Apr 2004 19:03:30 -0400 Original-Received: from [199.232.76.164] (helo=fencepost.gnu.org) by monty-python.gnu.org with esmtp (Exim 4.30) id 1BGnDe-0007ET-Jb for emacs-devel@gnu.org; Thu, 22 Apr 2004 19:02:58 -0400 Original-Received: from fencepost.gnu.org ([127.0.0.1] helo=lola.goethe.zz) by fencepost.gnu.org with esmtp (Exim 4.24) id 1BGnC8-00086u-Bm; Thu, 22 Apr 2004 19:01:24 -0400 Original-To: storm@cua.dk (Kim F. Storm) In-Reply-To: Original-Lines: 68 User-Agent: Gnus/5.09 (Gnus v5.9.0) Emacs/21.3.50 X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.4 Precedence: list List-Id: "Emacs development discussions." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: emacs-devel-bounces+emacs-devel=quimby.gnus.org@gnu.org Xref: main.gmane.org gmane.emacs.devel:22051 X-Report-Spam: http://spam.gmane.org/gmane.emacs.devel:22051 storm@cua.dk (Kim F. Storm) writes: > Richard Stallman writes: > > > However, I have fixed the treatment of newline characters > > so that non-empty lines are no longer made a minimum > > height equal to the frame default line height. > > > > That could have bad effects in many cases. > > I honestly don't understand why this is a problem. For instance, preview-latex uses images as a substitute for characters. If I have a line that looks like $x$ I still want to have it keep the full line distance to the previous line in order to avoid inconsistent spacing. This is existing usage of images. In contrast, sliced images have no existing usage. For this reason alone, it would be more useful to put the burden of removing the interline space on applications wanting seamless joining of images rather than on applications that want the normal spacing to be kept: we already _have_ applications that assume they need to do nothing special in order to keep the normal line spacing. > Quite contrary, I always found it very odd (i.e. buggy) that emacs > forces all lines to be at least as high as the default frame line > height. That means that you cannot have any "fine print". That's why I proposed to take the line spacing corresponding to the face valid on the new-line character (we'd need something like a null-face with zero metrics) or have something like a line-distance property we could tack onto it. Instead of the line spacing for the newline, one could also take the largest line spacing prevalent in the line _including_ the newline (as I explained above, there are existing applications of image-only lines which need to have a non-zero line spacing). That way we would still be able to do properly spaced fine-print. > Of course, I can change this, but my feeling is that the new > behaviour is more in line with what people would expect, Existing preview-latex code expects to be spaced like text by default. Your change would make some future special-case code slightly easier, at the cost of complicating existing uses. I think we can do this with less negative impact on existing usage, at just a small cost for future uses: just make it easy to specify explicitly when you want zero line spacing. > If you really have an application where you want to force the old > behaviour (I doubt there are currently any such uses), preview-latex uses glyphs as a replacement for characters. And it allows a line to consist just of images. So there are such uses right now. > there are ways to force the line to be shown with the default line > height (e.g. use a 'display space property with a zero width and a > height of 1 -- ok, that is currently not supported, but it could > easily be added). I think it would be less contrived to force the line spacing to zero by putting a suitable property on the newline. -- David Kastrup, Kriemhildstr. 15, 44793 Bochum