spanner question

[David Stocker]

Hello folks,

I have a question about a text spanner in a pre-defined variable.

In the snippet below, the first example does everything I want except 
that in the first line of music, the spanner line doesn't extend to the 
barline at the end of the line. I've achieved this by using two 
pre-defined variables for the text spanner I want: one to start it, and 
one to finish it with a terminal ending.

In the second example, the spanner extends to the end of the first line 
of music (with a terminal ending that I *don't* want) and then, starts 
too far to the left on the second line. The terminal ending at the 
conclusion of the chord acts the way I want it to.

My goal is to define a single variable (perhaps a music function) that 
will fulfill these requirements:

   * Extends over multiple systems, extending to the last measure's
     barline without the terminal ending
   * Picks up at the beginning of subsequent lines with identical
     positioning as the initiation of the spanner
   * Dynamically adds a terminal ending to the end of the spanner

Has anyone worked on this issue already (possibly with a scheme function)?

Also, the final destination for this is most probably going to be a 
"\include" file with many (dozens?) pre-defined variables for common 
text spanners used in guitar music. If I achieve the results I hope for, 
I plan to share it with the community.

Thanks,

David


Here's the snippet:

%%% begin ly snippet %%%

\version "2.13.1"

harmOn = {
 \override Voice.NoteHead  #'style = #'harmonic-mixed
 \tieDashed
} %% Set harmonics to diamond noteheads with dashed ties

harmXII = {
 \override TextSpanner #'(bound-details left text) = \markup { \teeny 
\upright"Arm. XII " }
 \once \override TextSpanner #'(bound-details right padding) = #-0.75
 \once \override TextSpanner #'(bound-details left padding) = #-0.25
 \once \override TextSpanner #'(bound-details left stencil-align-dir-y) 
= #CENTER
}

harmXIIterm = {
 \override TextSpanner #'(bound-details left text) = \markup { \teeny 
\upright"Arm. XII " }
 \override TextSpanner #'(bound-details right text) = \markup { 
\draw-line #'(0 . -0.75) }
 \once \override TextSpanner #'(bound-details right padding) = #-0.75
 \once \override TextSpanner #'(bound-details left padding) = #-0.25
 \once \override TextSpanner #'(bound-details left stencil-align-dir-y) 
= #CENTER
}

exOne= {
 \relative c' {
   \harmOn
   \harmXII
   \textSpannerUp
   \mark \markup { \bold "Example 1" }
   <e a d g b e>1~ \startTextSpan | <e a d g b e>1 | <e a d g b e>1~ | 
<e a d g b e>1 \stopTextSpan \break \harmXIIterm <e a d g b e>1~ 
\startTextSpan <e a d g b e> \stopTextSpan \bar "||"
 }
}

exTwo = {
 \relative c' {
   \harmOn
   \harmXIIterm
   \textSpannerUp
   \mark \markup { \bold "Example 2" }
<e a d g b e>1~ \startTextSpan | <e a d g b e>1 | <e a d g b e>1~ | <e a 
d g b e>1 \break <e a d g b e>1~ <e a d g b e> \stopTextSpan \bar "||"
 }
}

\score {
 \exOne
}

\score {
 \exTwo
}

%%% end ly snippet %%%