Getting font parameters in MkIV

Getting font parameters in MkIV

[Oliver Buerschaper]

Dear all,

how can I access font parameters (e.g. the thickness of the fraction rule) of an OpenType font in MkIV? Taco once gave me the solution:

---
\usetypescript[cambria]
\setupbodyfont[cambria]

\def\defaultrulethickness{\the\fontdimen8\textfont3\relax}



\starttext

\the\defaultrulethickness

\stoptext
---

which used to work in the old MkII days. Now with MkIV I get:

---
! Font \nullfont has only 7 fontdimen parameters.
<to be read again>
\relax
l.10 \the\defaultrulethickness

?
---

What's the new method to obtain the desired parameters?

Best wishes,
Oliver
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___________________________________________________________________________________

Re: Getting font parameters in MkIV

[Oliver Buerschaper]

> ---
> \usetypescript[cambria]
> \setupbodyfont[cambria]
> 
> \def\defaultrulethickness{\the\fontdimen8\textfont3\relax}
> 
> 
> 
> \starttext
> 
> \the\defaultrulethickness
> 
> \stoptext
> ---
> 
> which used to work in the old MkII days.

That is with the first two lines commented out :-)
___________________________________________________________________________________
If your question is of interest to others as well, please add an entry to the Wiki!

maillist : ntg-context@ntg.nl / http://www.ntg.nl/mailman/listinfo/ntg-context
webpage  : http://www.pragma-ade.nl / http://tex.aanhet.net
archive  : http://foundry.supelec.fr/projects/contextrev/
wiki     : http://contextgarden.net
___________________________________________________________________________________

Re: Getting font parameters in MkIV

[Oliver Buerschaper]

>> ---
>> \usetypescript[cambria]
>> \setupbodyfont[cambria]
>> 
>> \def\defaultrulethickness{\the\fontdimen8\textfont3\relax}
>> 
>> 
>> 
>> \starttext
>> 
>> \the\defaultrulethickness
>> 
>> \stoptext
>> ---
>> 
>> which used to work in the old MkII days.
> 
> That is with the first two lines commented out :-)

I was finally able to come up with this:

---
\usetypescript[cambria]
\setupbodyfont[cambria]



\starttext

FractionRuleThickness (in display style): \the\Umathfractionrule\displaystyle

FractionRuleThickness (in script style): \the\Umathfractionrule\scriptstyle

etc.

\stoptext
---

This should work with any font in MkIV. More parameters can be found in the LuaTeX manual at

http://www.luatex.org/svn/trunk/manual/luatexref-t.pdf

in section 5.4 on pages 114f. (Boy, did it take me time to discover this! Seriously.)

Oliver
___________________________________________________________________________________
If your question is of interest to others as well, please add an entry to the Wiki!

maillist : ntg-context@ntg.nl / http://www.ntg.nl/mailman/listinfo/ntg-context
webpage  : http://www.pragma-ade.nl / http://tex.aanhet.net
archive  : http://foundry.supelec.fr/projects/contextrev/
wiki     : http://contextgarden.net
___________________________________________________________________________________