> This should be documented as meaning "big points" (Adobe "points")
Agreed. You can support Points Cicero if you want, for all the Italians
out there, but I think it better not to. I have used a Compugraphic
typesetter where font sizes were in Anglo-American points and distances
were in Points Cicero, so that 10 on 10 point wasn't what you expected!!!
Numerically they are the same as Didot, as far as I know, except that
a Point Cicero in the 1880s was based on an 11pt pica.
If you think it's complex, be glad, it used to be worse by far :-)
> I would stay away from calling picas "pi".
Yes. Use "pica" or "picas" or (better) allow both.
There is no need for cryptic 2-letter abbreviations. If you are worried about
all the people typing those extra 2 characters, they can use an abbreviation
in their word processor, emacs, vi, or program an MS/DOS function key.
point/points/pt/pts (pt is OK for Point, so is plain p if you must)
pica/picas,
inch/inches
mm
cm/cms
m (metres, very optional, could also be miles :-))
em (a square of the current type size, e.g. 12 points when using a 12pt font)
en (0.5 em exactly)
diderot, dt (point diderot)
cicero (point cicero)
The definition of an Anglo-American point was originally
83 picas = 35 cm
12 points = 1 pica
The Didot point uses the French foot of 12.7892 American inches, and is
one 72nd of that.
Lee