From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.io!.POSTED.blaine.gmane.org!not-for-mail From: Juri Linkov Newsgroups: gmane.emacs.devel Subject: Re: Multi image PDF continuous mode Date: Mon, 10 Jan 2022 10:13:10 +0200 Organization: LINKOV.NET Message-ID: <86a6g5xa21.fsf@mail.linkov.net> References: <86lf0tq5zy.fsf@mail.linkov.net> <87ilvxinbn.fsf@logand.com> <86pmq5lf2o.fsf@mail.linkov.net> <86o84m2ky5.fsf@mail.linkov.net> Mime-Version: 1.0 Content-Type: text/plain Injection-Info: ciao.gmane.io; posting-host="blaine.gmane.org:116.202.254.214"; logging-data="31199"; mail-complaints-to="usenet@ciao.gmane.io" User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/29.0.50 (x86_64-pc-linux-gnu) Cc: Tomas Hlavaty , Emacs Devel To: dalanicolai Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane-mx.org@gnu.org Mon Jan 10 09:28:38 2022 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 1n6q2f-0007zY-G0 for ged-emacs-devel@m.gmane-mx.org; Mon, 10 Jan 2022 09:28:37 +0100 Original-Received: from localhost ([::1]:40478 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1n6q2e-0002Gv-Gy for ged-emacs-devel@m.gmane-mx.org; Mon, 10 Jan 2022 03:28:36 -0500 Original-Received: from eggs.gnu.org ([209.51.188.92]:46196) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1n6pzj-0000Hj-9M for emacs-devel@gnu.org; Mon, 10 Jan 2022 03:25:37 -0500 Original-Received: from [2001:4b98:dc4:8::227] (port=51903 helo=relay7-d.mail.gandi.net) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1n6pzg-0003EN-Va for emacs-devel@gnu.org; Mon, 10 Jan 2022 03:25:35 -0500 Original-Received: (Authenticated sender: juri@linkov.net) by relay7-d.mail.gandi.net (Postfix) with ESMTPSA id 17FAC2000E; Mon, 10 Jan 2022 08:25:25 +0000 (UTC) In-Reply-To: (dalanicolai@gmail.com's message of "Sat, 8 Jan 2022 22:32:51 +0100") X-Host-Lookup-Failed: Reverse DNS lookup failed for 2001:4b98:dc4:8::227 (failed) Received-SPF: pass client-ip=2001:4b98:dc4:8::227; envelope-from=juri@linkov.net; helo=relay7-d.mail.gandi.net X-Spam_score_int: -10 X-Spam_score: -1.1 X-Spam_bar: - X-Spam_report: (-1.1 / 5.0 requ) BAYES_00=-1.9, RDNS_NONE=0.793, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=no autolearn_force=no X-Spam_action: no action X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.29 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:284521 Archived-At: > Okay, so I have got a working Proof of Concept / core functionality. > You can very easily test it by loading the bookroll.el file from here, > then do `M-x br-test` and scroll using `j`/`k`. I will now focus on trying > to implement > it into pdf-tools, which is probably a little more work as its code is > quite complex/opaque. One problem is that the vertical scroll bar doesn't allow scrolling all images. >> Maybe then after a real image >> will be scrolled out of view, it could be replaced with a placeholder again >> to free memory. > > Haha, that is exactly what I meant with exactly that (the following) > sentence. This is nice that you already took care about this case. > > I would like to share my perspective on this, but before I do that, > > let me first ask you if you have any idea about why pdf-tools is not > part of > > Emacs. It is a very high quality package, that already lazily loads > the images, > > and provides many sophisticated features. > > It would be nice to include pdf-tools in Emacs, but I don't know > if the new maintainer has an intention to submit it for inclusion. > > > You might already be familiar with my 2-buffer continuous scroll hack > for it > > (which can be easily ported to doc-view mode, but 'developing' a > 'real' > > continuous scroll mode solution makes much more sense > > I agree, a real continuous scroll mode would be more preferable. > > > - I have created a, very rude but already nicely working, 'real' > continuous > > scroll proof of concept, for which, if you are interested, you can > find the > > code in this commit. It currently uses a trick where it only uses > two images > > at the time > > While two-images approach could provide better optimization for memory, > it has severe limitations, e.g. the vertical scroll bar can't be used > to scroll all images at once. > > > but as I will describe now, I think it will be better to create a > > 'bookroll' package for it. > > This is a promising direction. > > > I think the bookroll should not be so difficult to implement (I first > started to > > think about a general 'image-roll', but I think continuous scrolling > is > > generally not what you want for viewing/scrolling images > > Why not? 'image-roll' could be useful for the image gallery packages > like image-dired.el and thumbs.el. > > > So my current idea for how to implement it, is by > > immediately creating overlays for all pages in a single buffer and > fill them > > with 'empty' svg-images of the correct size (after testing this with > a thousand > > 'placeholders', it seems that the 'empty' images use almost no > memory). > > Good news, so loading a 1000-page document won't take much memory. > Only scrolling will load real images. Maybe then after a real image > will be scrolled out of view, it could be replaced with a placeholder > again > to free memory. > > > Then, the scrolling can be implemented, by changing the display > properties (from empty > > svg to real image, and back) and jumping to the correct positions > using > > `set-window-vscroll`. I have started on writing bookroll.el, of > course your > > joined efforts or feedback would be very much appreciated. Otherwise, > this short > > message serves just to inform you about these activities. > > Thanks, feel free to post updates about your progress > or when stuck on some problems.