# [luatex] Fribidi for LuaTeX

Vafa Khalighi vafa018 at gmail.com
Sun Jul 17 11:27:53 CEST 2011

```Thanks for this but after reading this for several times, I still have
difficulty understanding the actual problems. Maybe it is because I never
faced any of these issues. So I would be grateful if you could explain these
issues more clearly so that we can discuss them. On the other side (Knowing
that luatex is different to XeTeX), I guess that unibidi is done by the ICU
and I am not sure if any of these problems exist in XeTeX too, in XeTeX you
have some kind of unicode bidi if (1) you use any opentype font which uses
ICU and (2) the direction of each, say English word in RTL is LTR but not
two words, direction of numbers is LTR and obviously specific characters are
mirrored.

On Tue, Jul 12, 2011 at 11:51 PM, Taco Hoekwater <taco at elvenkind.com> wrote:

>
> Hi,
>
> Now that the Unicode BiDi algorithm implementation discussion
> seems to restart, it is a good time to ask the people involved
> to solve the non-trivial problem of adjusting the algorithm
> to cater for the inclusion of
>
> * out-of-line node objects (\setbox, \box, \copy),
> * out-of-line tokens (like alignment templates and macro expansions),
> * vertical typesetting,
> * TeX grouping levels,
> * Interfering nodes (math, \special, \rule etc)
>