From: Stefan Monnier <monnier@iro.umontreal.ca>
To: help-gnu-emacs@gnu.org
Subject: Re: relative line numbers and folding: how to make they play along?
Date: Fri, 15 Jul 2016 09:53:44 -0400 [thread overview]
Message-ID: <jwvfurbm3aq.fsf-monnier+gmane.emacs.help@gnu.org> (raw)
In-Reply-To: 83mvlj7513.fsf@gnu.org
>> >> Actually, I don't think there needs to be flickering if the first step
>> >> ("perform redisplay of window") just computes the new matrices without
>> >> performing any drawing.
>> > Since the display engine computes the number of each screen line as it
>> > lays them out, I don't understand why would 2 phases be needed. I'm
>> > probably missing something.
>> If we bake it into the redisplay code, we can indeed do it "on the fly",
>> but if we want this feature to be implemented in Elisp it seems a lot
>> more tricky to avoid the 2 passes.
> But this sub-thread started with you talking about baking it into
> redisplay:
By "help from the display engine" I meant that we'd need to make
changes to the C code, but I didn't mean to bake it in.
> These two passes are described in terms of what redisplay does, they
> are not visible to Lisp: we don't return to the command loop after
> each window's redisplay, and the glyph matrices are not exposed to
> Lisp, either.
I didn't mean to return to the command-loop in-between.
I was more thinking of the situation I mentioned in some other
discussion: rewrite the top-level of the redisplay code in Elisp,
basically a function which:
- asks the C code which windows need to be redisplayed.
- call a C function on each of those windows to recompute the matrices.
- detect the case where point is out of the window, and either move
point and call the recompute-matrices function, or call another
C function to do the scrolling.
- then call a C function on each window/frame to update the display.
From there we can hope to provide a more efficient/robust follow-mode
(while still implementing it in Elisp). And in that context, we should
also be able to provide a more efficient relative-visual-linum-mode, tho
it might require yet more access, such as subrs to scan/read the
matrices, and maybe other subrs to modify the matrices (to update the
margin).
Some of those primitives would probably also be useful in order to write
tests of the redisplay code.
I think such a change should be doable without a complete rewrite of
the redisplay. But it would undoubtedly take a fair bit of work.
Stefan
next prev parent reply other threads:[~2016-07-15 13:53 UTC|newest]
Thread overview: 27+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-07-11 15:11 relative line numbers and folding: how to make they play along? Filipe Silva
2016-07-12 4:51 ` Eli Zaretskii
2016-07-13 3:43 ` Filipe Silva
2016-07-13 20:10 ` Stefan Monnier
2016-07-13 20:23 ` Eli Zaretskii
2016-07-13 22:33 ` Filipe Silva
2016-07-14 15:02 ` Eli Zaretskii
[not found] ` <mailman.1359.1468449224.26859.help-gnu-emacs@gnu.org>
2016-07-14 1:29 ` Dan Espen
2016-07-14 2:36 ` Stefan Monnier
2016-07-14 15:06 ` Eli Zaretskii
2016-07-14 15:55 ` Filipe Silva
2016-07-14 15:58 ` Filipe Silva
2016-07-14 16:12 ` Eli Zaretskii
2016-07-14 16:51 ` Filipe Silva
2016-07-14 18:23 ` Boris
2016-07-14 21:03 ` Stefan Monnier
2016-07-15 0:04 ` Filipe Silva
2016-07-15 0:18 ` Stefan Monnier
2016-07-15 0:41 ` Filipe
2016-07-15 7:07 ` Eli Zaretskii
2016-07-15 13:53 ` Stefan Monnier [this message]
2016-07-15 14:22 ` Eli Zaretskii
2016-07-15 14:54 ` Stefan Monnier
2016-07-15 15:34 ` Filipe Silva
[not found] ` <mailman.1414.1468511758.26859.help-gnu-emacs@gnu.org>
2016-07-15 2:02 ` Dan Espen
[not found] ` <mailman.1374.1468463825.26859.help-gnu-emacs@gnu.org>
2016-07-14 3:20 ` Rusi
2016-07-14 12:17 ` Stefan Monnier
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=jwvfurbm3aq.fsf-monnier+gmane.emacs.help@gnu.org \
--to=monnier@iro.umontreal.ca \
--cc=help-gnu-emacs@gnu.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
Code repositories for project(s) associated with this external index
https://git.savannah.gnu.org/cgit/emacs.git
https://git.savannah.gnu.org/cgit/emacs/org-mode.git
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.