Re: Add option to indicate frets by letters in tablature (issue164063)

[demery]

> Dana suggests "course", which I guess speaks well to lute players.  But
> not
> to guitar players.

12 course guitar anyone?

maybe ts a classical guitar hing, but I also remember tutorials discussing
6-course instruments.


> I had envisioned that a full set of fretLetters would be given

At least that, saving keystrokes is not a good idea here.  Wht is really 
needed is a way to specify degenerated ligatures; as I have said, for
german tab the ligatures used by 16c printers (and later) included
overstrikes using both curved and straight line segments placed below,
thru, and above the main glyph, each positioned differently from others. 
I began a font for these, but got sidetracked and havent gone back to it.

> Perhaps we just ought to define lists called fretLabels (instead of
> fretLetters).  And we could then define lists of any kind of glyphs to be
> used.

Flags, mensural symbols (O2, O3, O/...), bars (| || |:|  :|:  :|  |: |||,
this last is a common ornamental flourish used for the final bar, the
second vertical stroke is repeated several times all connected, the height
of it degenerates into, well, a flourish).  In some renaissance editions
it is clearly a cast type sort, others use various woodcuts chosen to fill
available space; perhaps the user will be inconcistant in how it is used,
epsf-cum-woodcut or font character.

While I use separate dots flags and stems when devising a font, they are
pre-compounded and are encoded as one non-combining symbol to the font
user.  However, other font makers may solve that issue differently,
leaving it up to the user to form ligatures from parts like tails, dots,
stems.  Tabulature flags with dots are usually shown above the staff
(Petrucci's editions are an exception), so there is no issue of the dot
intersecting a line, as is seen in notes on a mensural staff; mensural
notation requires a different placement of the dot of augmentation
relative to its note when the note is on a line as opposed to when it is
in a space, which is a reason to have them be combining symbols in a
mensural font.

> There could be specific lists for each different style of tablature,
> that would be very easy to switch to.

If ly needs musical semantics to associate with the symbols then there
will be an issue to consider as well, the display symbol lists will need
coordination with similar lists for the semantic(s).

Historical usage varied as to the symbols employed and how they map to
duration.  The usual set of 5 flags were simply up-stemmed notes (usually,
but not always headless) with tails to the right - semibreve, minim,
semiminim, fusa, semifusa.  Some printers also had a breve - a left-going
tail, or a tailless stem with a circle on it.

Many polyphonic editions show (by comparing parallel score parts with the
tab) that those flags were read in proportion (ie, the written semibreve
was read as breve); this to avoid needing  5-flagged stems that would
challenge the punchcutter, the player, compositor, and proofreader with
weak eyes, and the ink that spreads.

--
Dana Emery