Re: Issue 754: don't transpose generic property-setting music commands (issue 7303057)

[dak]

On 2013/02/08 04:46:27, Keith wrote:
> Yesterday's patch was better.

I beg to differ.  It did not address instrument definitions, or manual
settings of instrumentTransposition.

> The 'untransposable property is more closely related to the source of
the events
> (\transposition or \instrumentSwitch) than to the event type (override
or
> propertySet).

To be perfectly clear about this: untransposability is related to
individual properties.  instrumentTransposition should be untransposable
no matter how it is being set.

One problem is that "untransposable" is a very coarse tool compared to,
say, the callback system for \relative.


https://codereview.appspot.com/7303057/diff/2001/scm/define-music-types.scm
> File scm/define-music-types.scm (right):


https://codereview.appspot.com/7303057/diff/2001/scm/define-music-types.scm#newcode379
> scm/define-music-types.scm:379: (untransposable . #t)
> Well, not every Grob property that is a pitch is untransposable. The
second
> pitch in a pitchedTrill, for example, should be transposed along with
the first
> pitch.

I don't see that there is any interface for pitched Trills that would
ride on explicit property setting commands.

And don't you think it strange that if you use \override for setting a
property, the pitches get transposed, whereas if you use \tweak for
setting a property, the pitch does not get transposed?  Where is the
logic with that?

> Do we need to remember to avoid \override on those that are
transposable?

I don't see anybody using \override here on pitched trills.  And yes: it
would appear that for things sufficiently sophisticated to require
transposition, one would want an own music type.


https://codereview.appspot.com/7303057/diff/2001/scm/define-music-types.scm#newcode446
> scm/define-music-types.scm:446: (untransposable . #t)
> Not every context property that is a pitch is untransposable. The
tonic of the
> Staff, for example.

The tonic of the Staff is set via KeyChangeEvent, not via PropertySet.
It is not manipulated independently from the scale.

https://codereview.appspot.com/7303057/