[math-font-discuss] Ugly drawn rules in Adobe Reader

[Taco Hoekwater]

Hi,

At bachotek2005 there was a talk about the Latin Modern fonts,
and there was a small math example included, of course. The
presentation was shown using adobe's PDF reader, and as you
probably know, it displays the rules TeX draws for fractions
and the radical bar horribly.

I volunteered to write a patch file for pdftex to mend this
problem (by using a character instead of a rule), but am a bit
unsure about the 'best' solution, and I vaguely remember that
possibly somebody had done something with \radical a long time
ago already, so I thought I'd ask and see what you think.

At the moment, I believe that is probably easiest to create something
similar to \delimiter, specifying both a family and a char (with
one \rulechar character per math "set", that is used for all the
"rule drawing" routines like \atop.... and \radical.

This is not invasive (and therefore easy to implement), and the
input files can remain backward compatible.

On the other hand, there is also the possibility to change the
TFM  format, so that a char can have a charlist as well as being
extensible. I doubt that is feasible without breaking backward
compatibility (and it would be a lot more work also).

But even for the first possibility, A number of options are
possible like having different ones with different widths or
automatically stretching/shrinking or using different ones for
scriptscript sizes, or using the character only for \atop..
and \radicals but not for \overbar, etc.

What do you think? What is the nicest solution?

Greetings, Taco