[XeTeX] Fwd: what units are the slant and embolden font features?

[Will Robertson]

Hi all,

A little while ago the following thread appeared in c.t.t., recently 
re-opened by the original author:

> 	From:	Pander <pander at users.sourceforge.net>
> 	Subject:	Re: What units have FakeSlant (slant) and FakeBold (embolden)?
> 
> On Sep 10, 3:51 pm, Will Robertson <wsp... at gmail.com> wrote:
>> On 2009-09-10 17:47:24 +0930, Pander <pan... at users.sourceforge.net> said:
>> 
>>> Hi all,
>> 
>>> What units have FakeSlant and FakeBold which are offered by the fontspe
> c
>>> package but can also be used directly as slant andemboldenin
>>> @update at family?
>> 
>>> Support you would like to formulate a sentence like: "The fake
>>> slant/bold is 0.1 XXX." What would XXX be in order to convey to non TeX
>>> users what you have been doing with a type.
>> 
>> Hmmm, I can't remember. Actually I don't think I ever knew. If you find
>> out, let me know and I'll document it :)
>> 
>> Thanks,
>> Will
> 
> This:
>   grep embolden -riI /usr/local/texlive/*|grep -v bibtex|grep -v
> fontspec
> is not really helpful.
> 
> Does anyone know how to figure this out?

I'm lazy/busy at the moment so I can't investigate this straight away; 
does anyone know the answer?

Cheers,
Will