Scarlatti, polyphony within a keyboard score

[David Fedoruk]

Hello:

Scarlatti "looks" simple but of course is not. I'm using a Longo
edition to create a basic score which I will  edit (hopefully) from
the Kirkpatrick facsimile into a performing edition.

I have this specific problem for the moment which wil lead to another
question about schemes.

----------- Sscoe Snip ----------

\version 2.11.27

\include "english.ly"

Sonata_Emajor_K530.ly
    \version "2.10.25"
        

    upper = \relative c'' {
       \clef treble
       \key e \major
       \time 3/4

        e b fs  r4 r8 \bar "||"                       % Bar 20
        
        \key e \minor r8  b''8 \grace a16 g8  fs e d | % Bar 21
\override Staff.NoteCollision # merge-differently-dotted = ##t  
        << {       c,2 \stemUp a'4 | } >> \\          % bar 22
        \grace b16 c2.  |
         }

   lower = \relative c {
       \clef bass
       \key e \major
       \time 3/4

        r4  r8 e' b fs \bar "||"                              % Bar 20
        
        \key e \minor e4 r4 r  |                                        % Bar 21
        r8 a''8 fs8 ds  cs b |                                  % Bar 22
        
        

    }

    \score {
       \new PianoStaff <<
          \set PianoStaff.instrumentName = "Piano  "
          \new Staff = "upper" \upper
          \new Staff = "lower" \lower
       >>
       \layout { }
                
       \midi { }
                
    }

------------------ end Score -------------

This renders, but not as it is supposed to. The right hand should have
a second voice joining and the dotted half c and half note c should be
the same note with stems going both up and down. Instead it renders as
if it were new bars of consecutive score,

I also get this Guile error: error:

--------- snip -----

GUILE signaled an error for the expression beginning here
\override Staff.NoteCollision #
                               merge-differently-dotted = ##t
Unbound variable: merge-differently-dotted

----- snip ----

The line breeaks in the error are as they appear when I invoke
lilypond in the shell.

First, I think I do no quite undersand the override and collision and
Second, have I added the new polyphonic voice correctly?

Do I need to put something in the scheme definitions about these new
polyphonic bits? The occur with regularity in this peice but are
transitory in nature. They last a few measures then the voice simply
disappears as is not uncommon in piano scores.

Cheers,
David

--
David Fedoruk
B.Mus. UBC,1986
Certificate in Internet Systems Administration, UBC, 2003


http://recordjackethistorian.wordpress.com
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