Transposable Fret Diagrams for Guitar

[Carl D. Sorensen]

I'm proposing a method for getting transposable fret diagrams for the
guitar.

The method I propose is different from the current FretBoard
functionality.  The FretBoard context takes a set of notes and
determines a fingering that will allow the playing of that set of notes.
This is a very useful too, and I appreciate Rick for sponsoring it.

I've asked Han-Wen about the cost for sponsoring a modification to
FretBoards that will allow it also to take the name of a chord and
determine a chord diagram.  There would be a default set of chord
diagrams (one for each chord name) that I would enter based on a
standard chord reference for guitar.  Then, the input to FretBoards
would be a set of chord names (which Lilypond will change into a set of
chords).  If the sequence were transposed, the chords would be
transposed.  The diagrams would be looked up in a hash table and
included in the score.  Any chords not found in the hash table would be
treated just as in the current FretBoards context -- a fingering would
be determined by FretBoards.

Of course, if users wished, they'd be able to define their own chord
library (I assume the library will be defined in a .ly file), or replace
entries in the existing chord library.  And the current functions of
FretBoard will still be available.

The cost for sponsoring this feature is eur 150.  I'm hoping to get a
couple of people to help me sponsor this feature.  Any takers?

Thanks,

Carl Sorensen