[XeTeX] Problems with thickness of \frac rule and width of accents (\hat) with XeLaTeX

[Ulrik Vieth]

On 08/17/2010 10:12 PM, Khaled Hosny wrote:
>
> Hmm, thinking a bit more, this is likely to break legacy math control
> sequences that has no equivalent in unicode-math yet, which will
> currently just grap a glyph from CM, more seriously, it will break
> \overbrace and likes since XeTeX support seems not working and
> unicode-math is simply using the CM constructs for those.

Good question. Perhaps one might argue that unicode-math should not rely 
on anything to be taken from CM.  If something is not readily available 
in XeTeX such as \overbrace, it should probably provide its own 
redefinition in terms of Unicode slots (if that is possible). However, 
this might also get trick in terms of which building blocks are encoded 
as Unicode slots or only in the Private Use Area.

Hmmm, this probably still needs more thinking...

Regards, Ulrik.