[tablatures] planned doc edits fretted-strings.itely

[Patrick Schmidt <p.l.schmidt@xxxxxx>]

Hi Carl, Marc et al.

I have prepared some material to document the new harmonic functions.  
I think it should be placed at the end of "Default tablatures". I'm  
planning to split up the existing paragraph on harmonics and slides  
into two separate paragraphs. The slides-paragraph would contain  
different kinds of slides and chord glissandi which I have not  
finished yet. The existing harmonics/slides-snippet would be replaced.

I created a snippet to demonstrate all three methods of engraving  
open-string harmonics. I also added some sort of a reference for open- 
string harmonics as I think it might not be obvious to everybody  
which fret/ratio leads to which harmonic pitch. Finally I'd like to  
illustrate how fretted-string harmonics can be typeset with LilyPond  
as they need a different approach.

Before I prepare a patch I'd like to know whether my snippets are  
appropriate for the docs. Should anything be changed/left out? Is  
anything missing? Should the fretted-string harmonics go into  
"Selected snippets"...
[Of course the three score-markups won't go into the docs.]

Thanks for your help,

patrick

\version "2.13.41"

\paper {
  indent = 0\mm
  ragged-right = ##t
}

\layout { }

openStringHarmonics = {
  \override StringNumber #'add-stem-support = ##t
  \ottava #1
  <d'\4\harmonic>16
  <g'\3\harmonic>16
  <b'\2\harmonic>8
  \harmonicByFret #7 < a\4 d'\3 fis'\2 >4
  \ottava #2
  \harmonicByFret #5 { c'16\3 e'16\2 a'8\1 }
  \harmonicByRatio #2/5 < b'\4 e'\3 gis'\2 >4
}
\markup{"Open-string harmonics"}
\score {
  <<
    \new Staff {
      \new Voice {
        \clef "treble_8"
        \openStringHarmonics
      }
    }
    \new TabStaff {
      \new TabVoice {
        \openStringHarmonics
      }
    }
  >>
}

openStringHarmonics = {
  %first harmonic
  \harmonicByFret #12 e,2\6_\markup{"1st harm."}
  \harmonicByRatio #1/2 e,\6
  %second harmonic
  \harmonicByFret #7 e,\6_\markup{"2nd harm. - - - -"}
  \harmonicByRatio #1/3 e,\6
  \harmonicByFret #19 e,\6
  \harmonicByRatio #2/3 e,\6
  %\harmonicByFret #19 < e,\6 a,\5 d\4 >
  %\harmonicByRatio #2/3 < e,\6 a,\5 d\4 >
  %third harmonic
  \harmonicByFret #5 e,\6_\markup{"3rd harm. - - - -"}
  \harmonicByRatio #1/4 e,\6
  \harmonicByFret #24 e,\6
  \harmonicByRatio #3/4 e,\6
  \break
  %fourth harmonic
  \harmonicByFret #4 e,\6_\markup{"4th harm. - - - - - - - - - - - -  
- -"}
  \harmonicByRatio #1/5 e,\6
  \harmonicByFret #9 e,\6
  \harmonicByRatio #2/5 e,\6
  \harmonicByFret #16 e,\6
  \harmonicByRatio #3/5 e,\6
  %fifth harmonic
  \harmonicByFret #3 e,\6_\markup{"5th harm."}
  \harmonicByRatio #1/6 e,\6
  \break
  %sixth harmonic
  \harmonicByFret #2.7 e,\6_\markup{"6th harm."}
  \harmonicByRatio #1/7 e,\6
  %seventh harmonic
  \harmonicByFret #2.3 e,\6_\markup{"7th harm."}
  \harmonicByRatio #1/8 e,\6
  %eighth harmonic
  \harmonicByFret #2 e,\6_\markup{"8th harm."}
  \harmonicByRatio #1/9 e,\6
}

\markup{"Reference for open-string harmonics"}
\score {
  <<
    \new Staff {
      \new Voice {
        \clef "treble_8"
        \openStringHarmonics
      }
    }
    \new TabStaff {
      \new TabVoice {
        \openStringHarmonics
      }
    }
  >>
}

PH = {
   \textSpannerDown
   \override TextSpanner #'bound-details #'left #'text =
      \markup {\halign #-0.5 \teeny "PH" }
      \override TextSpanner #'style =
         #'dashed-line
   \override TextSpanner #'dash-period = #0.6
   \override TextSpanner #'bound-details #'right #'attach-dir = #1
   \override TextSpanner #'bound-details #'right #'text =
      \markup { \draw-line #'(0 . 1) }
   \override TextSpanner #'bound-details #'right #'padding = #-0.5
}

harmonics = {
  %artificial harmonics (AH)
  \textLengthOn
  <\parenthesize b b''\harmonic>4_\markup{ \teeny "AH 16" }
  <\parenthesize g g''\harmonic>4_\markup{ \teeny "AH 17" }
  <\parenthesize d' d'''\harmonic>2_\markup{ \teeny "AH 19" }
  %pinched harmonics (PH)
  \PH
  <a'\harmonic>2\startTextSpan
  <g'\harmonic>4
  <e'\harmonic>4\stopTextSpan
  %tapped harmonics (TH)
  <\parenthesize g\4 g'\harmonic>4_\markup{ \teeny "TH 17" }
  <\parenthesize a\4 a'\harmonic>4_\markup{ \teeny "TH 19" }
  <\parenthesize c'\3 c''\harmonic>2_\markup{ \teeny "TH 17" }
  %touch harmonics (TCH)
  a4( <e''\harmonic>2. )_\markup{ \teeny "TCH" }
}

frettedStrings = {
  %artificial harmonics (AH)
  \harmonicByFret #4 b4\3
  \harmonicByFret #5 g4\4
  \harmonicByFret #7 d'2\3
  %pinched harmonics (PH)
  \harmonicByFret #7 a2\4
  \harmonicByFret #5 g4\4
  \harmonicByFret #7 e4\5
  %tapped harmonics (TH)
  \harmonicByFret #5 g4\4
  \harmonicByFret #5 a4\4
  \harmonicByFret #4 c'2\3
  %touch harmonics (TCH)
  a4 \harmonicByFret #9 e'2.\3
}

\markup{"Fretted-string harmonics"}
\score {
  <<
    \new Staff {
      \new Voice {
        \clef "treble_8"
        \harmonics
      }
    }
    \new TabStaff {
      \new TabVoice {
        \frettedStrings
      }
    }
  >>
}