[XeTeX] Microtypography?

[Ralf Stubner]

Jonathan Kew <jonathan_kew at sil.org> writes:

> On 10 May 2006, at 11:36 pm, Will Robertson wrote:
>
>> Off the top of my head, I'm pretty sure that the AAT font format can
>> support optical protrusion,
>
> Yes, the 'opbd' table is defined for that purpose. And if it were  
> present in the font, XeTeX could use it.

Would that also be true for OpenType fonts with the (equally named)
'opbd' feature? Or would that require additional coding in ICU(?) first?
I don't have a font that supports this feature, but I could build one,
once I really understand how the OT specs are to be interpreted wrt to
'opbd' and its relation to 'rtbd' and 'ltbd'.

cheerio
ralf