On Sun, Sep 19, 2010 at 7:50 PM, Joseph Wakeling <joseph.wakel...@webdrake.net> wrote: > >From a notational perspective, the first two numbers are used to > calculate the vertical staff position of the notehead, while the value > of the alteration is used to determine the accidental: e.g. (1,1,-1/2) > corresponds to the D-flat a semitone above middle C. > > *A key assumption of this approach is that there is a one-to-one > correspondence between accidental and alteration value.* This clearly > holds for conventional Western 12-tone notation. However, it does _not_ > hold for many _microtonal_ notations. > > For example, if we are using the very common 'arrow' notation for > quarter-tones, there are two distinct accidentals that can be used to > represent the alteration +1/4 (i.e. quarter-tone-sharp): the first is a > natural sign with an up arrow, the second is a sharp sign with a down > arrow. There is currently no effective, well-defined way to indicate > which of the two is desired at any given moment. > > The arrow quarter-tone notation is just one of a whole variety of > microtonal notations which operate not on the basis of single symbols > per alteration, but on the basis of asuperposition of a successive > hierarchy of symbols, each corresponding to smaller and smaller shadings > up or down of the pitch. For example: > > sharp/flat + up/down arrow + plus/minus > +/- 1/2 +/- 1/4 +/- 1/8 > > Lilypond's consideration of pitch alteration as a single number makes it > very difficult to adequately represent such hierarchical > pitch-alterations, and hence their corresponding notations.
This is not the nuance implied, since by your definition, natural-uparrow (+1/4) and sharp-downarrow are the same, and you clearly want them to mean something different. What is the difference between both? I have not followed the discussion in detail, but the requirements for any (replacement) pitch representation is: - pitches can be transposed by pitches (deltas relative to central C), ie. it is a representation that is closed wrt transposition - there is a unique mapping from pitch to semitones (ie. for midi playback) - it can represent classical pitches (ie. octave,step,alteration) unambiguously. The current system satisfies these constraints obviously, but it possibly does not represent well various nuances of scales that may exist. -- Han-Wen Nienhuys - han...@xs4all.nl - http://www.xs4all.nl/~hanwen _______________________________________________ lilypond-devel mailing list lilypond-devel@gnu.org http://lists.gnu.org/mailman/listinfo/lilypond-devel
