[Groff] Re: UTF-8/Unicode for groff

[Werner LEMBERG]

> I'm working on extending groff to support UTF-8-encoded Unicode
> input.

This is good news!

>  (I hope this isn't duplicating work someone else is already doing!)

AFAIK, no.  The latest thing was utf8 output for ttys.

>   (1) Is it reasonable to represent Unicode characters that do not
>       map directly onto any character in the standard troff
>       character set as names corresponding to their Unicode
>       character numbers?  For example, I am representing Unicode
>       character U+1234 (Ethiopic syllable See) as troff character
>       \[U+1234].  I didn't want to use just character numbers in
>       case there are output devices that use radically different
>       numbering schemes.

I would rather suggest to use a new escape, `\U' (which is still
unused fortunately) for that.  It should behave similarly to \N but
(a) accepts hexadecimal input and (b) doesn't map to charN but to uniN
(to follow the Adobe Glyph List specification.  Have you considered
the more serious problems of combining characters (not to mention the
reordering of glyphs)?

>   (2) For Unicode characters that do not appear in the current font,
>       I have set it up to automatically substitute bitmap versions
>       of the characters.  These are created spontaneously from Roman
>       Czyborra's "unifont" font whenever troff finds it cannot
>       locate a U+xxxx character, and are accomplished through the
>       equivalent of .char with a series of \h, \v, and \D to draw
>       the bitmapped image.  I'm not terribly happy with this, but it
>       seems better than not being able to do anything at all with
>       the characters.

Hmm, what about mounting this fallback font as a special font?  This
should be sufficient, shouldn't it?  Maybe we have to develop a
special syntax in case groff becomes too slow (or too memory hungry)


    Werner