New \partcombine in 2.19 Was: Re: Combining voices in American Hymns

[David F.]

On Sep 8, 2016, at 2:09 AM, Phil Holmes <address@hidden> wrote:

> Partcombine has been improved in 2.19.  See 
> http://lilypond.org/doc/v2.19/Documentation/notation/multiple-voices#automatic-part-combining

Ah, yes.  That looks very close to what I want.  In fact \partcombine #'(1 . 0) 
appears to do the trick.

But I do not understand what the two new arguments do.  The documentation 
linked above has a paragraph that tries to explain the new arguments, but I 
simply do not understand.  Also, some quick experimentation didn’t shed any 
more light.

\version "2.19"
instrumentOne = \relative {
  c'1 |
  b2 c |
  a4 b c d |
}

instrumentTwo = \relative {
  c'1 |
  c2 c |
  c4 c c c |
}

<<
  % These all generate the same output
  \new Staff \partcombine \instrumentOne \instrumentTwo
  \new Staff \partcombine #'(0 . 0) \instrumentOne \instrumentTwo
  \new Staff \partcombine #'(0 . 1) \instrumentOne \instrumentTwo
  \new Staff \partcombine #'(0 . 2) \instrumentOne \instrumentTwo
  \new Staff \partcombine #'(0 . 3) \instrumentOne \instrumentTwo

  % These all generate the same output
  \new Staff \partcombine #'(1 . 0) \instrumentOne \instrumentTwo
  \new Staff \partcombine #'(1 . 1) \instrumentOne \instrumentTwo
  \new Staff \partcombine #'(1 . 2) \instrumentOne \instrumentTwo
  \new Staff \partcombine #'(1 . 3) \instrumentOne \instrumentTwo
  \new Staff \partcombine #'(2 . 0) \instrumentOne \instrumentTwo
  \new Staff \partcombine #'(2 . 1) \instrumentOne \instrumentTwo
  \new Staff \partcombine #'(2 . 2) \instrumentOne \instrumentTwo
  \new Staff \partcombine #'(2 . 3) \instrumentOne \instrumentTwo
  \new Staff \partcombine #'(3 . 0) \instrumentOne \instrumentTwo
  \new Staff \partcombine #'(3 . 1) \instrumentOne \instrumentTwo
  \new Staff \partcombine #'(3 . 2) \instrumentOne \instrumentTwo
  \new Staff \partcombine #'(3 . 3) \instrumentOne \instrumentTwo
>>

Also, Lilypond 2.19 is 5x to 10x slower on my Mac.

David