[luatex] Unicode math issue with LuaLaTeX

[Ulrik Vieth]

On 06/13/2010 01:55 AM, Ulrik Vieth wrote:
>
> Could it be that some of the TFM-based \Umathradical... parameters
> from cmsy + cmex in \fam2 + \fam3 are retained instead of applying
> the OpenType math parameters from XITSMath in \fam 4?
>
> Traditional \TeX always used to treat \fam2 + \fam3 as the source
> of global \fontdimen parameters applicable to all font families.
> Does this still hold for LuaTeX? Does it no longer apply for XeTeX?
>
> Could it be that unicode-math.sty is taking an inappropriate approach
> by loading the new OpenType math font into a new family, instead of
> replacing and overriding the default value in \fam2 + \fam3?

After a bit of thinking, I wonder if LuaTeX should reconsider its
approach to handling OpenType math font parameters:

For example, if you load CambriaMath, AsanaMath and XITSMath into
\fam 4, 5, 6, and each comes with its own set of OT math parameters, why 
should any set of parameters from \fam 2 + \fam 3 apply globally?

  Why not take the parameters directly from each font in the case of
OpenType and apply the global defaults only in the case of TFM fonts?
Apparently, that seems to be the way that XeTeX handles this case.

Regards, Ulrik