Asana Math Oversized "Big operators"

Question

I am having this problem when using Asana Math with XeLaTeX + unicode-math, if you see the pdf found in the download link AsanaProb.zip you can see that \bigcap produces much bigger character than it should:

Is it a syntax problem or maybe something else? The document compiled on a linux machine with texlive 2010 if that helps...

Answer 1

Update: the new version is already on CTAN.

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It's a bug with Asana Math. I've contacted Apostolos Syropoulos, the author, and he'll probably release a new version soon.

The issue (which I uncovered thanks to Khaled Hosny) is twofold. First, unlike other TeX Fonts, but like Cambria Math, Asana has multiple versions of its big math operators. Usually there's only one, which is the \displaystyle version of the operator. This can be seen by opening the font in fontforge and looking at its MATH table, in the section vertical variants.

The second part is that the font constant DisplayOperatorMinHeight was set too high, to 1850. As the name indicates, this constant indicates the minimum height a glyph needs to be considered the display version of a math operator. But the "correct" display version of the \bigcap operator has a height of only 1559, thus not qualifying for display. The engine then looked for the next version, which has heigh 2588, and selected it. This is the huge glyph you're seeing.

The first part is important because if there weren't other variations, the engine would just settle for the "small" display operator.

If you can't wait for the bugfix release of Asana and are using luatex, the font can be patched on-the-fly with this code (copied from here):

\usepackage{unicode-math}
\usepackage{luacode}
\begin{luacode*}
  local function patch_asana(fontdata)
    local mc = fontdata.MathConstants
    if mc then
      mc.DisplayOperatorMinHeight = 1337
    end
  end
  luatexbase.add_to_callback("luaotfload.patch_font", patch_asana, "patch_asana")
\end{luacode*}
\setmathfont{Asana Math}

Answer 2

I expect this is just the way the operators are designed to look. (Can someone verify this?)

If you don't like it, you could define an alternative smaller bigcap like so:

\newcommand{\altbigcap}{\scalebox{0.8}{\bigcap}}

(0.8 might not be appropriate, I can't check since I don't think I have the relevant font, I don't think...)

An alternative solution would be to recycle the answers to this question to suit your purpose: replace the bigcap symbol with one from a different font.

Answer 3

(Repeated from my answer at the PhilTeX forums.)

I'm actually getting a reverse problem when trying \bigcap with unicode-math and Asana Math: the result looks too small. I can't quite figure it out at the moment. We seem to be using the same version of the package. Out of curiousity, are you using a 32 or 64 bit version of Linux? I know there seems to be some bad mojo between 64 bit linux and unicode-math (which may explain why I'm having trouble).

I think this largely a matter of taste. I don't think that cap looks so big that it couldn't be intended to be that big. What I find jarring, however, is that it is bigger than the bounded product sign, which looks bad just because it is inconsistent.

Along kind of similar lines to Seamus's suggestion, my own suggestion would be to try loading the relsize package

\usepackage{relsize}

and redefine \bigcap like this in the preamble:

   \let\oldbigcap\bigcap
   \renewcommand{\bigcap}{\mathop{\mathsmaller{\oldbigcap}}}

But the problem I'm having with the package right now prevents me from testing that code.

You can iterate \mathsmaller commands to make it smaller and smaller.