Proposal for BiDi in terminal emulators

[Eli Zaretskii via Unicode]

> Date: Sat, 2 Feb 2019 23:02:10 +0100
> Cc: unicode at unicode.org
> From: Egmont Koblinger via Unicode <unicode at unicode.org>
> 
> On top of this, I make the clarification that combining marks need to
> be reordered to be sent out to the terminal emulator _after_ their
> base letter

That is true in general regarding any text shaping: the shaping engine
needs the characters to be submitted in the logical order.  When Emacs
works on a text-mode terminal, it sends characters to be shaped
together, such as base character and its combining marks, in logical
order, even when the surrounding text is reordered into visual order.

> What I add is another mode (the technically less problematic
> "implicit" mode where the terminal displays the contents just as any
> BiDi-aware graphical text editor, browser etc. would do) for the
> sake of "cat"-like simple utilities

I think there are hard problems even for such "simple" utilities, and
I will start a separate thread about this.