Re: instrumentSwitch and addInstrumentDefinition use

[Keith OHara]

Paul Scott <waterhorse <at> ultrasw.com> writes:

> Is anyone using instrumentSwitch that can explain what the various 
> variables in addInstrumentDefinition mean?

Don't use instrumentSwitch.  It is a pointless frustrating waste of time.
(The same could be said for LilyPond, except that there is sometimes a
point to wasting time with LilyPond.)

You can define a variable with the things that change each time you
switch instruments, without learning the instrument switch data structure
  piccolo = { \transposition c'' \clef "treble^8"  }

> AFAIK I really only 
> want the key signature to change automatically when I do an 
> instrument switch.

I am guessing that you input pitches as written for the instrument.
(If you write in concert pitch and then transpose for the instruments
then what I say next will not apply.)

This is a missing function of LilyPond. 
One awkwardness is that LilyPond considers the key signature to be 
individual to each Staff.  It was created by horn players, and horn parts
traditionally omit the key signature.  So LilyPond does not store a global
key signature.

We could, I think, keep this organization, and write a variant of
"\tranposition bes"  that looks up the old key-signature and old 
transposition on the Staff, figures the concert key, applies the new
transposition, figures the new key-signature for the new transposition
and sets that new key signature.

I just write an explicit \key d\major at the instrument switch when needed
(which is not very often)

> Almost everything is copied from NM 1.6.3

Let's change that section
https://codereview.appspot.com/133390043/diff/80001/Documentation/notation/
staff.itely

> #'(
This has to be a back-quote ` instead of a forward quote '