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bigop positioning
- To: math-font-discuss@cogs.susx.ac.uk
- Subject: bigop positioning
- From: alanje@cogs.susx.ac.uk (Alan Jeffrey)
- Date: Fri, 20 Aug 93 20:22 BST
>Yes my question is still unanswered. I thought there were some TeXperts on
>this list ?
Now dat's fightin' talk :-)
>My questions are: Why are the bigoperators in cmex set under the baseline?
I think the answer is that only DEK knows, but the rest of us can guess.
My theories...
As far as TeX is concerned, it doesn't matter where the big ops are,
as long as their bottom is below or touching the baseline and their
top is above or touching the baseline. These conditions have to be
true, otherwise the big ops won't be centered properly.
DEK *could* have put the bigops into their `natural' place, and I
believe that with the default CM parameters this wouldn't have
violated the constraints above. But there may be parameter settings
for CMEX (with a high math_axis# and low dh# for example) when this
would have resulted in the constraints being violated.
In addition, by putting the glyph below the baseline, if it is used in
any way other than as a math character of type Op, the results are
obviously wrong, rather than being slightly wrong (as would be the
case if the glyphs were above the baseline). And there's something to
be said for failures happening in a dramatic fashion so that they're
noticable!
But this is complete guesswork...
Alan.