Re: Stem: flag-style

[Juergen Reuter]

Mats writes:
> > * Actually, the stroke does not strike the flag, but rather the whole
> >   stem.  Hence, it should not be called *flag*-style.  In particular,
> >   I think I have already seen a stroke being added to a crotchet,
> >   which does not have a flag attached onto its stem (although I
> >   currently can not remember a definite reference for such a case).
>
> Yes, this was quite common during the baroque period to 
> denote different versions of arpeggio. Often the dash is
> drawn between the note heads of a chord but I've also
> seen it drawn through the stem of a quarter note, for example
> in the ornament table by d'Anglebert that Jeremie sent out
> some months ago.

Han-Wen writes:
> > * Currently, flag-style only supports the two distinct String values
> >   "" and "grace".
>
> Sure, but may be we'd better be sure that these are the only values.

Ok, I had a look in my copy of the Harvard Dictionary of Music (HDM),
published in 1972, under the entries "Grace note", "Grace",
"Nachschlag", "Appogiatura", "Slide", "Apogiatura, double", "Slur" (a
special kind of double appogiatura), and "Ornamentation".

After reading all these articles, I think the bottom line is that
there are many different ornaments with many different signs.  The
signs are placed over the notes, between the notes or by striking the
stem (not the flag); many of them are alternative (e.g. an Mordent may
be indicated via a curved line after the note head, by a zig-zag line
with a stroke over the note, or by two parallel lines over the note).
Regarding the stroke problem, the key sentence (from article
"Appogiatura", pp. 43-45) is:

"A few composers wrote the long appogiatura as a small note of the
exact value in which it should be performed and distinguished the
short appogiatura from it by means of a single stroke across the stem
(for a 16th note) or a double stroke (for a 32nd note), but this
practice was by no means consistently carried out."

There is no further notion of attaching any other symbols to or
printing them across the stem.

MGG contains an article called "Verzierungen" (MGG vol. 13,
col. 1526-1556), written in 1966, which is 16 pages long and discusses
many ornaments from the middle-ages to romanticism and tracks the
development over time for many countries separately.  I did not fully
read it, but from quickly scanning over it, I think it is much more
detailed than HDM, but the bottom line is roughly the same.  Regarding
the double stroke, however, it says: "Trotz zahlreicher Bemuehungen
vor allem engl. Musikforscher konnte die Bedeutung der beiden von den
Virginalisten verwendeten Verzierungszeichen, des 'single stroke' und
des 'double stroke', bis heute nicht geklaert werden".  (Translation:
"Despite of multiple affords of especially English music scientists,
the meaning of the two grace note symbols that were used by the
Virginalists, the 'single stroke' and the 'double stroke', could not
be solved by today.")  As an example, the article contains a figure
with a crotchet with a single stroke and a crotchet with a double
stroke.

Since HDM is from 1972 and often cites MGG, but differs in the
interpretation of the strokes, I wonder if music science has advanced
on this specific topic between 1966 and 1972, or if the terms 'single
stroke' and 'double stroke' apply to different notation symbols and/or
different epoches, or if simply one of the two sources is wrong.

Anyway, I think the topic needs more discussion, though my feeling is
that there will be only a single boolean 'stroke' in lily that can be
turned on or off.  But I will probably keep the property 'flag-style'
untouched for the moment and introduce a new property 'style' for the
stem as a whole, as suggested (though it will currently apply to the
flag only).

Greetings,
           Juergen