Proposal for BiDi in terminal emulators

[Khaled Hosny via Unicode]

On Fri, Feb 01, 2019 at 06:57:43PM +0000, Richard Wordingham via Unicode wrote:
> On Fri, 1 Feb 2019 13:02:45 +0200
> Khaled Hosny via Unicode <unicode at unicode.org> wrote:
> 
> > On Thu, Jan 31, 2019 at 11:17:19PM +0000, Richard Wordingham via
> > Unicode wrote:
> > > On Thu, 31 Jan 2019 12:46:48 +0100
> > > Egmont Koblinger <egmont at gmail.com> wrote:
> > > 
> > > No.  How many cells do CJK ideographs occupy?  We've had a strong
> > > hint that a medial BEH should occupy one cell, while an isolated
> > > BEH should occupy two.  
> > 
> > Monospaced Arabic fonts (there are not that many of them) are designed
> > so that all forms occupy just one cell (most even including the
> > mandatory lam-alef ligatures), unlike CJK fonts.
> > 
> > I can imagine the terminal restricting itself to monspaced fonts,
> > disable “liga” feature just in case, and expect the font to well
> > behave. Any other magic is likely to fail.
> 
> Of course, strictly speaking, a monospaced font cannot support harakat
> as Egmont has proposed.

There are two approaches for handling them in monospaced fonts;
combining them with base characters as usual, or as spacing characters
placed next to their bases. The later approach is a bit unusual, but
makes editing heavily voweled text a bit more pleasant. It requires good
OpenType support, though, so virtually no terminal supports it.

Regards,
Khaled
-------------- next part --------------
A non-text attachment was scrubbed...
Name: ALMFixed.png
Type: image/png
Size: 12872 bytes
Desc: not available
URL: <http://unicode.org/pipermail/unicode/attachments/20190202/7cc684c5/attachment.png>