Re: Align metronome mark at time signature or first musical element. Fixes #684. (issue1579041)

[jan . nieuwenhuizen]

Hi Neil,

Not sure how to find the email address to bind this
to http://codereview.appspot.com/1579041 ?

> http://codereview.appspot.com/1579041/diff/19001/20003#newcode82
> lily/metronome-engraver.cc:82: == ly_symbol2scm ("staff-bar"))
> can't this be incorporated into 'break-align-symbols for
MetronomeMark?

Alas, it can't.  When adding staff-bar to that list, the broken
marks appear next to the bar numbers, right at the start of the
staves.

> though I'd prefer more lisp-like syntax for this using
> camel_case_to_lisp_identifier ()

Done.

> http://codereview.appspot.com/1579041/diff/19001/20006#newcode610
> scm/define-grob-properties.scm:610: (non-break-align-symbols ,list? "A
list of
> symbols that determine
> needs adding to an interface

Added to the break-aligned-interface.

> http://codereview.appspot.com/1579041/diff/19001/20007
> File scm/define-grobs.scm (right):

> http://codereview.appspot.com/1579041/diff/19001/20007#newcode418
> scm/define-grobs.scm:418: metronome-mark
> Is this necessary?

> IIUC, only break-aligned grobs will be acknowledged by the
Break_align_engraver,
> so a MetronomeMark will never appear in the list of elements for
ordering.

Okay...so I've added the break-aligned-interface.  It makes sense
to have this position added - this is probably not the only symbol
that we want positioned like this?

> http://codereview.appspot.com/1579041/diff/19001/20007#newcode1161
> scm/define-grobs.scm:1161: break-alignable-interface
> + self-alignment-interface

> otherwise regtests spit out loads of warnings for missing interface
(from
> self-alignment-X setting)

Added.

http://codereview.appspot.com/1579041/show