Re: eqn sqrt and pdf?

[Tadziu Hoffmann]

> i didn't know gv can render pdf files and it happens it's
> the only one to render math.pdf the file correctly.

gv uses ghostscript (gs) to render the pages, and ghostscript
provides its own fonts.

> pdffonts math.pdf
> shows that Symbol is not emb. i thought fonts were always
> embeded in pdf files...

Nowadays even Adobe recommends that _all_ fonts be embedded,
but when PDF was first designed, it was expected that every
PDF renderer provide the so-called "base 13" fonts (Times,
Helvetica, and Courier in the usual four variants each,
plus Symbol), so these were not required to be embedded.

> yet: i'm not sure about what to be fixed.

Register all fonts you're using in the "download"
files in devps and devpdf (usually
/usr/share/groff/current/font/dev{ps,pdf}/download).

grops (devps) is okay with

Symbol path/to/Symbol.pfa

but gropdf (devpdf) requires tabs as field separators
(see the gropdf manual page):

<tab>Symbol<tab>path/to/Symbol.pfa

where <tab> is an actual tab character.

Replace path/to/Symbol.pfa with the path to the actual
Symbol font on your system.

grops wants .pfa files (which you can create from .pfb files
using pfbtops) and requires _relative_ paths, but for gropdf
the following also appears to work:

<tab>Symbol<tab>/usr/share/ghostscript/fonts/s050000l.pfb

despite that font actually being called "StandardSymL" and
not "Symbol".  (Whether this may cause inconsistencies
later on if you mix it with documents using Adobe's
"Symbol" font I do not know.)