Fret Diagram markup

[Han-Wen Nienhuys]

address@hidden writes:
> I've been toying with the implications of developing a fret-diagram
> context and engraver.  It seems to me that one of the major benefits to
> having a context and engraver, rather than a markup, is that it allows
> transposition to be applied to music expressions.  But I don't see how
> transposition will work properly on the notes for a chord diagram.  If I
> transpose from c to d, I don't want to play a C chord with all strings
> up two frets.  Instead, I want to shift to a D chord, which has an
> entirely different string structure.

that's a correct observation. However, another neat thing of music &
engravers is that we can build syntax especially for frets, which
make  the red tape

      \markup { \fret #1 #" .. " }

superfluous. Also, it would be easier to align the frets with the
notes.

In the long run it would be cool to translate the result of \chords {}
(ie. the collection of pitches) to a fret diagram. This could be done
by means of table lookup.

I would like to start integrating your file into scm/fret-diagrams.scm
- however, could I ask you to use hyphenated chord names? When
fret-diagrams.scm enters the Lilypond distribution, we have to take
over maintainership (for name changes in the Scheme API).  Having a
uniform coding style really helps us work with the code.

--
 Han-Wen Nienhuys   |   address@hidden   |   http://www.xs4all.nl/~hanwen