Re: "Final" version of tty child frames

[Gerd Möllmann]

Eli Zaretskii <eliz@gnu.org> writes:

>> From: Gerd Möllmann <gerd.moellmann@gmail.com>
>> Cc: Emacs Devel <emacs-devel@gnu.org>
>> Date: Wed, 23 Oct 2024 07:00:03 +0200
>> 
>> Another question is if there is something lurking with R2L? I have no
>> idea what terminals do in that case, but I'd guess Eli knows :-).
>
> Terminals should do nothing, and if your terminal emulator has a "bidi
> reordering" feature, you should disable it, because Emacs does
> everything by itself, and needs the terminal to be "dumb" in this
> aspect.
>
> Basically, we produce a glyph row where all the glyphs are flushed to
> the right window edge, and there's empty space on the left of each
> screen line to make it a full-width screen line.  The low-level write
> code that writes to the terminal then works normally, writing glyphs
> left to right.

Thanks, that's good to know for sure.

>
> The current branch hits an assertion violation when showing RTL text
> in a child window.  (Showing RTL text in the parent window works
> fine.)  Here's the recipe:
>
>  emacs -Q -nw
>  Evaluate in *scratch:
>
>     (defun my-make-child ()
>       (interactive)
>       (make-frame `((parent-frame . ,(selected-frame))
>                   (background-color . "gray10")
>                   (foreground-color . "white")
>                   (internal-border-width . 1)
>                   (top . 15)
>                   (left . 40)
>                   (width . 80)
>                   (height . 25))))
>
>  M-x my-make-child RET
>  C-x 5 o
>  C-x C-f etc/tutorials/TUTORIAL.he RET

I'll have a look, a bit later.