Re: [Heirloom] Using the Symbola font in Heirloom troff

[T. Kurt Bond]

Looking at the postscript output there is a "/uni1F0A1 9429 def" and a
"/uni1F10A" in a "/Encoding-@15@36 [...] def"; is that part of the font
machinery?  (I'm sadly ignorant of PostScript, alas.)

Looking at troff/troff.d/otf.c
<https://github.com/n-t-roff/heirloom-doctools/blob/f3a16e2ba0c411441fd5de5340be73674bd51307/troff/troff.d/otf.c#L1481>
I see that there is a struct WGL
<https://github.com/n-t-roff/heirloom-doctools/blob/f3a16e2ba0c411441fd5de5340be73674bd51307/troff/troff.d/otf.c#L845>
that
contains female
<https://github.com/n-t-roff/heirloom-doctools/blob/f3a16e2ba0c411441fd5de5340be73674bd51307/troff/troff.d/otf.c#L1481>
and male
<https://github.com/n-t-roff/heirloom-doctools/blob/f3a16e2ba0c411441fd5de5340be73674bd51307/troff/troff.d/otf.c#L1482>
entries.  At the beginning of the struct is a comment
<https://github.com/n-t-roff/heirloom-doctools/blob/f3a16e2ba0c411441fd5de5340be73674bd51307/troff/troff.d/otf.c#L848>
that
consists of "/* WGL4 */".  Googling that led to Windows Glyph List 4
<https://en.wikipedia.org/wiki/Windows_Glyph_List_4>.  Taking a leap, I
added the unicode characters FEMALE SIGN and MALE SIGN to my test
document.  Those show up fine in the final PDF output.  Maybe this is
connected?  At this point I suspect without much evidence
<https://github.com/n-t-roff/heirloom-doctools/blob/f3a16e2ba0c411441fd5de5340be73674bd51307/troff/troff.d/otf.c#L1502>
that characters that are not in the StandardStrings
<https://github.com/n-t-roff/heirloom-doctools/blob/f3a16e2ba0c411441fd5de5340be73674bd51307/troff/troff.d/otf.c#L186>
array, the MacintoshStrings
<https://github.com/n-t-roff/heirloom-doctools/blob/f3a16e2ba0c411441fd5de5340be73674bd51307/troff/troff.d/otf.c#L582>
array, or the WGL
<https://github.com/n-t-roff/heirloom-doctools/blob/f3a16e2ba0c411441fd5de5340be73674bd51307/troff/troff.d/otf.c#L848>
array don't get output.  Maybe.  I'll have to investigate some more.

On Tue, Aug 4, 2020 at 11:10 PM Richard Morse <pukku@mac.com> wrote:

> Hm. Just for my edification, I tried a few things.
>
> I’m on a Mac, and I don’t know when I compiled Heirloom troff, but it was
> a year or two ago, so something things may be different.
>
> I downloaded the Symbola font from fontlibrary.org. The version I got was
> .ttf, not .otf.
>
> The various things that you tried did not work for me either. \[u1F0A1]
> did work, but that’s because (according to fret, at least), that’s the
> font’s internal name for the symbol, which is not guaranteed to be true
> across all fonts, so you can’t really use that for a “fallback” system.
>
> Looking at the output of troff without going through dpost, it looks like
> it is completely ignoring the character. I tried explicitly setting
> LC_CTYPE to ‘en_US.UTF-8’ and ‘UTF-8’ (both in the terminal, and using the
> .lc_ctype command), but that had no effect.
>
> I wonder if troff has a compiled in list of unicode characters that it
> understands, and if you try to use one it deems invalid it just ignores it?
> (This may be borne out by
> https://github.com/n-t-roff/heirloom-doctools/blob/master/troff/troff.d/unimap.c
> , but I don’t really know enough about the code to be certain.)
>
> Ricky
>
> > On Aug 4, 2020, at 10:14 PM, T. Kurt Bond <tkurtbond@gmail.com> wrote:
> >
> > In Emacs M-x describe-coding-system tells me the coding system for
> saving the buffer is utf-8-unix.  I don't have any LC_* environment
> variables set, but LANG=en_US.UTF-8.
> >
> > I'm not very knowledgeable about the insides of Unicode fonts,
> unfortunately.
> >
> > On Tue, Aug 4, 2020 at 4:27 PM Richard Morse <pukku@mac.com> wrote:
> > Huh. I’m afraid I’m out of my depth then; you might check and see if
> your LC_* environment variables are set to something incompatible with
> utf-8 (or, maybe, check and make sure the file in UTF-8, not UCS-16 or
> something if you’re on Windows), but hopefully someone with more experience
> and knowledge will speak up…
> >
> > Ricky
> >
> > > On Aug 4, 2020, at 3:59 PM, T. Kurt Bond <tkurtbond@gmail.com> wrote:
> > >
> > > And if I add "and explicit unicode character reference \U'1F0A1'" to
> the
> > > file, that character doesn't show up either.
> > >
> > > On Tue, Aug 4, 2020 at 2:47 PM Richard Morse <pukku@mac.com> wrote:
> > >
> > >> According to the Heirloom Troff manual, I think that you cannot just
> > >> insert Unicode characters (although maybe if your LC* environment
> variables
> > >> are set correctly, you can?). It says:
> > >>
> > >>> Both nroff and troff allow references to specific Unicode characters
> > >> with the \U'X' escape sequence;
> > >>> it causes the character at position U+X to be printed (X is a
> > >> hexadecimal number). For troff,
> > >>> it is required that this character is available in one of the fonts
> > >> mounted at this point.
> > >>> As an example, \U'20AC' prints the Euro character €. When register
> .g is
> > >> set to 1 Unicode
> > >>> characters can also be accessed with \[uXXXX] where XXXX is a four
> digit
> > >> hexadecimal number.
> > >>
> > >> So I think you would need to use `\U'1F0A1'` for the character to
> show up?
> > >>
> > >> Ricky
> > >>
> > >>
> > >>> On Aug 4, 2020, at 12:28 PM, T. Kurt Bond <tkurtbond@gmail.com>
> wrote:
> > >>>
> > >>> (The heirloom-doctools README.md
> > >>> <https://github.com/n-t-roff/heirloom-doctools/blob/master/README.md
> >
> > >> says
> > >>> to ask Heirloom doctools questions on this list.)
> > >>>
> > >>> I'd like to use the Symbola font in Heirloom troff.   I tried the
> > >> following:
> > >>>
> > >>> .do xflag 3
> > >>> .\" fp 5 Optima Optima-Regular ttf
> > >>> .fp 5 Symbola Symbola otf
> > >>> .LP
> > >>> Here is some normal text.
> > >>> .\" PLAYING CARD ACE OF SPACES is Unicode 0x1F0A1
> > >>> .ft Symbola
> > >>> 🂡 And some normal text. ❊
> > >>> .ft P
> > >>> More normal text.
> > >>>
> > >>> That's a literal PLAYING CARD ACE OF SPADES Unicode character at the
> > >> start
> > >>> of the line between the two .ft requests.  That character does not
> show
> > >> up
> > >>> in the troff output, even through the EIGHT TEARDROP-SPOKED PROPELLER
> > >>> ASTERISK Unicode character at the end of the line *does* show up,
> > >>> as CPSuni274A where the CPS<name> outputs the character of that name.
> > >> The
> > >>> Symbola font is embedded in the PDF output (created from the
> PostScript
> > >>> output), and the text "And some normal text" and the EIGHT
> > >> TEARDROP-SPOKED
> > >>> PROPELLER ASTERISK Unicode character are in the Symbola font in the
> troff
> > >>> output.
> > >>>
> > >>> However, if I manually add a CPSuni1F0A1 to the troff output, *that*
> > >> character
> > >>> *does* show up.
> > >>>
> > >>> Any ideas as to why the literal PLAYING CARD ACE OF SPADES Unicode
> > >>> character in the document source is being ignored and not written to
> the
> > >>> troff output?
> > >>>
> > >>> I actually have a document that needs to use the PLAYING CARD ACE OF
> > >> SPADES
> > >>> Unicode character.  The ultimate goal is to have the Symbola font
> used
> > >> as a
> > >>> fallback font, which should happen automatically in Heirloom troff,
> since
> > >>> it searches all the fonts when a font is missing a character, but I
> made
> > >>> the example use the Symbola font directly because that shows the
> problem
> > >>> directly.
> > >>>
> > >>> --
> > >>> T. Kurt Bond, tkurtbond@gmail.com, https://tkurtbond.github.io
> > >>
> > >>
> > >
> > > --
> > > T. Kurt Bond, tkurtbond@gmail.com, https://tkurtbond.github.io
> >
> >
> >
> > --
> > T. Kurt Bond, tkurtbond@gmail.com, https://tkurtbond.github.io
>
>

-- 
T. Kurt Bond, tkurtbond@gmail.com, https://tkurtbond.github.io