Re: how to add barre indications to automatic fret diagrams?

[Carl Sorensen]

On 5/21/15 1:30 AM, "pls" <address@hidden> wrote:

>
>Nice! Thanks a lot.
>
>Yes, transposing chords with open strings probably poses a problem.
>Fingering information would have to be included automatically in order to
>decide whether they should be part of a barre.  I¹d think it¹s safe to
>assume that transposed open strings in chords will always be played with
>the first finger.

For right now, transposing chords with open strings will leave the strings
open.  Transposing doesn't affect fingering, only pitches.

I'm actually OK with that.  An E chord (with open 6, 2, and 1) is a
different shape from an F chord (with barred 6, 2, and 1) in my opinion.
Yes, the pattern on strings 3, 4, and 5 is the same.  But the hand pattern
on the chord is different.

I thought about this issue quite a bit when I was creating predefined fret
diagrams.  There, we introduced the idea of a chord shape.  There is a
function that shifts a chord shape by N frets (offset-fret).  At present,
it adds N to the fret number for every dot.  I thought about setting the
fret number to N for every open string, but elected not to do it because I
wouldn't know what to do with the finger.  I guess it's possible to set it
to 1.

The fundamental issue that causes the problem is that a fingering of 0 not
only sets a finger, but also a fret.

However, you can easily fix this yourself in your chords that request
automatic fret diagrams.  Set the finger to 1, and if the automatic
diagram asks for a fret of 0, it will automatically change it to zero.

\new FretBoards {
  <e,-1 b,-3 e-4 gis-2 b-1  e'-1>1
  \transpose e f <e,-1 b,-3 e-4 gis-2 b-1  e'-1>1
  <f,-1 c-3 f-4 a-2 c'-1 f'-1>1
  \transpose f e  <f,-1 c-3 f-4 a-2 c'-1 f'-1>1
   
  }

Thanks,

Carl