[XeTeX] XeTeX and Arabic

[Jonathan Kew]

On 15 Jun 2004, at 1:41 pm, Musa Furber wrote:

> Mr. Kew,
>
> Now that my segmentation fault problem is fixed (many thanks to both 
> you and Adam Lindsay, and my apologies to everyone else for the slurry 
> of messages), I tried the Arabic.tex example with the (very small) 
> catalog of Arabic fonts I have.
>
> The Arabic fonts shipped with OS X worked as expected and desired.
>
> The fonts I have from elsewhere (Windows, for example) behave as 
> expected but not as desired: the proper letter is shown, but not the 
> proper glyph given the adjacent letter. I wrote "expected," because 
> this is what often happen in other applications; changing the font to 
> one of the Arabic fonts shipped with OS X fixes the problem.
>
> Is there any way to solve this?
>

The OS X fonts work because they include AAT (Apple Advanced 
Typography) tables that control the selection of joining forms of the 
letters, etc.

If you have OpenType fonts (such as those , you need to specify the 
Arabic script tag when loading the font, so as to get the correct 
behavior; see the ArabicOpenType example. Something like:

	\font\myfont="ArabicFontName:script=arab"

This should work for fonts that include the GSUB/GPOS tables that 
OpenType layout uses.

Hope this helps,

Jonathan