You might be wondering what am I talking about, ain't I
already used Nroff macro to write gopher posts? Yes, that is
true, and I have found Nroff to be a very useful tool to
format texts for line printers and terminal.
I use Heirloom Doctools, if you don't know, was from
OpenSolaris, instead of the now de-facto GNU roff. Groff
does not support UTF-8, and the version installed on macOS
is too old, and sometimes Groff just does too much that
hides the detail of how roff is supposed to work, which is
why I don't like to use it. I know you are urging to ask
what about neatroff, but I'll postpone that to later.
By the way, Plan 9 roff is also inherited from UNIX
source, so it is somewhat compatible with Heirloom's and the
macros can be shared, and thanks to the overall Unicode sup-
port Plan 9 has, it also supports UTF-8 out of box.
Coming early than TeX, roff is a macro system designed
for a model that you are going to output instructions on how
to move the print head, and select the glyph to type. This
model fits well for both line printers and phototypesetter.
My headache is, and as it always will be, typing equa-
tions. The Nroff output is not really suitable for Xterm or
VT100 terminal emulators, as they lacks the essential over-
strike feature, and even with col and less this could some-
what be achieved there is no way to emulate scroll back half
line and type in-between the two lines.
That is why neqn output would never look good again,
unless you happened to have one of the obscure line printers
supported by Unixes.
Now for the phototypesetter backend. Sorry, all the
phototypesetter backends were removed from existing troff
distributions and the only supported one is Adobe's
PostScript. Another painful fact is the only full featured
PostScript distiller available for general personal desktop
publishing use is Ghostscript. Adobe has their PS distiller
shipped with their Acrobat Pro downloads, and you can use
that without need to dealing with DRMs (the whole absurd
Creative Cloud stuff), but its features are limited, and
Adobe only license the full PS interpreter to businesses at
a very high fee (3000 USD per year?). Apple has their own
closed source PostScript distiller implementation, that is
now depreciated. As for hardware, the high end printers all
supports PDF instead now, and even for those still keeps PS
support, the PS is internally converted to PDF first.
That all concludes that PostScript, the only format
left for troff's phototypesetting output is already fading.
Troff uses the default font provided by PS distiller,
Times-Roman, Courier, just to name a few. The cursed fact
outside the alphabets, the special characters that is sup-
posed to be used for equation typesetting, are all different
from Ghostscript, Adobe's distiller, and Apple's distiller.
It seems only the font Ghostscript uses can properly render
equations typed by troff. And likely on the printer you are
going to use, they have a different variant of the special
font, so if you forget to embed the font your equation is
gonna be messed up (Don't ask me how I learned that).
Neatroff is not an extension to existing troff, it is a
rewrite based on models used by Groff and Unix troff. The
font handling is fragile, that apparently the tool it uses
to generate font metrics gives wrong parameters to special
symbols. Did I mention Heirloom can use TTF and OTF directly
(and uses correct font metrics)? Besides, It heavily depends
on Ghostscript for properly render equations, and I don't
have GS installed on my computer.
After all, both Neatroff and Heirloom troff does not
give better typesetting result, and the output consistently
is not as good as today's TeX which directly outputs PDFs.
Besides, their font handling system can in no way compare
with XeTeX or LuaTeX. So have my word, don't spend time on
troff when you already have TeX!
