[luatex] Fribidi for LuaTeX

[Khaled Hosny]

On Tue, Jul 12, 2011 at 03:51:24PM +0200, Taco Hoekwater 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)

Some questions from me:

* local_par whatsit:
  - it is always the 1st node in the list (if exists at all), right?
  - \textdir inserts begindir node after it, is this a general rule? (I
    noticed when I insert begindir nodes before it combining marks get
    shifted to the right, but it might be a bug in the font code).
  - what is the dir field is used for? I can query it but setting it (to
    TRT for example) has no effect (the par still left aligned).
* when \pardir is set to TRT while \textdir is still TLT luatex will
  enclose the paragraph with begindir/enddir TLT nodes (skipping the
  local_par etc.), right? if yes, is there anyway to suppress this?
* how can I set paragraph direction to TRT without setting \pardir,
  in pre_linebreak_filter?

Regards,
 Khaled

-- 
 Khaled Hosny
 Egyptian
 Arab