Dear abc users and devellopers,
meanwhile all originally planned tablature features are
realised in abctab2ps and I plan to do other music extensions,
mostly in the realm of "early music".
Before I introduce some other incompatible set of abc extensions,
I would like to ask the other devellopers whether and how
they already have addressed some of the following issues.
1) figured bass
Both abctab2p2 and abcm2ps support line breaks (\n) and accidentals
(\# \b \=) in guitar chords; I have adopted the syntax of abcm2ps
in order to be compatible. Although I think that natural signs
should be avoided in figured bass (most historic sources only use
b for diminished intervals and # for augmented intervals) because
they break transposibility, it was an oft requested feature.
There is still a problem: more than one different chord/figure on
a single note (eg. a "5\n4 3#" cadenza). Most historic sources place
the two figures centered above the bass note; most modern editions
however place them like an individual voice on the time axis.
As the second solution is more desirable for readability reasons,
I am looking for a solution to emulate it. A possible solution
could be a voice parameter to print only the guitar chords of this
voice as guitar chords above a different voice. Example:
V:Flute clef=treble space=+10 bracket=2
V:Bass clef=bass
V:figures figuresof=Bass
Any better ideas?
2) rhythm of "grace notes"
abc supports grace notes, which are printed by abc2ps as eigth notes
in reduced size. A single grace note is printed as an eigth note
with an oblique stroke (ie. a short appogiatura in 19th century
context).
While doing some transcriptions of viol sonatas, I need grace notes
which are not eigth notes. The straightforward implementation
(allowing rhythm factors in braces: {a//g//f//a//}) has a compatibility
issue: according to the old abc standard (or its interpretation that
was implemented in abc2ps), grace notes without a rhythm factor are
of the length 1/8 rather than that of the L: field.
Any suggestions?
3) meter ambiguity
In early music, M:C| can mean M:4/2, M:4/1 or M:4/4.
And triple time M:3 can mean M:3/2, M:3/1 or M:3/4.
In other words, the mathematical meter differs from the meter symbol.
Thus I would suggest that the M: filed always means the
mathematical meter (which is importand for automatic barnumbering),
and that a diverging meter symbol can be specified via a pseudocomment
like
%%metersymbol 4/1=C|
%%metersymbol 3/2=3
This could mean: print C| whenever the meter is 4/1 and 3 whenever
it is 3/2.
Unfortunately I had introduced the syntax M:3 which was quickly
adopted by J.F.Moine for abcm2ps and even extended to stuff like M:2.
Maybe we could withdraw this extension and replace it with the
pseudocomment solution?
4) more clef types
There are 3 different clefs (G, C and F) which can appear on different
staff lines. Which names are currently used for the various clefs
in the different abc-programs? What identifiers are used for the
french violin clef (G1) for instance?
I stop at this point, because if this mail becomes even longer
noone will read it ;)
Christoph Dalitz
To subscribe/unsubscribe, point your browser to: http://www.tullochgorm.com/lists.html
