Re: vertical centering of text in tbl rows

[Werner LEMBERG]

> With file1, the text is not vertically centered between the two
> lines.

Correct.

> Specifically, the distance between the top of the text and the top
> line is much smaller than between the bottom of the text and the
> bottom line.

Correct.

> Using old AT&T tbl/troff, the text is properly vertically centented.

I can't believe that.  Actually, if this is really the case then there
is a bug somewhere in AT&T, since all three calls to `.vs' in file2
move vertically by a fixed amount which is completely independent of
the actual dimensions of the glyphs in string `GOO'.

If you replace `GOO' with `(((((GOO)))))' you can see that the string
*is* vertically centered.  Since `GOO' has no glyphs with descenders,
the space below the string is larger than the space above.

Testing with heirloom troff + tbl, I get the same appearance as with
groff.


    Werner


PS: The AT&T snippet you are providing lacks some calls to `.br' --
    `.vs' doesn't cause a line break.