Michael Barr barr at math.mcgill.ca
Fri Oct 29 21:19:24 CEST 2010

On Fri, 29 Oct 2010, Philip Taylor (Webmaster, Ret'd) wrote:

> Michael Barr wrote:
>
>>  \documentstyle{article}
>>  \def\bbrack#1{[\![#1]\!]}
>>  \begin{document}
>>  $\bbrack{\widehat c =\widehat d}$
>>  \end{document}
>>
>>  Yes, I could add extra space after the argument, but that is a real
>>  kludge. My real question is why can't I get the \widehat to actually be
>>  centered over its argument. As you can see, it starts halfway along the
>>  "d" and ends well to the right. This is also true of the one on the "c"
>>  so it is not just centering over an ascender.
>
> Is it not centered w.r.t. the italic slope ?
> ** Phil.

I don't really care what it is centered with respect to.  It looks awful
and I don't expect tex to produce awful-looking output.  In all cases it
ought to be centered over the glyph, not some extension of the slope.