Re: Issue 787 in lilypond: script stack order fails with 2 more notes

[Carl Sorensen]

On 12/2/09 2:47 PM, "Neil Puttock" <address@hidden> wrote:

> 2009/12/2 Carl Sorensen <address@hidden>:
> 
>> But it seems to me that if outside-staff-priority is set for one grob, and
>> not for the other, then they should be compared by script-priority, since
>> there is *not* an outside-staff priority.
> 
> That's exactly what I mean: in the case above, the turn has no
> outside-staff-priority, but has a script-priority of 1 provided by the
> Script_engraver, so it's already the first element in the list (due to
> scm_stable_sort_x ()).

Oh, I had misunderstood.  Actually, according to gdb, the \turn has a
script-priority of 0.

> 
>> Does this mean we need to establish the outside-staff-priority for *all*
>> scripts?
> 
> No, since some aren't outside staff objects.  We could add
> script-priority defaults for all scripts, but I don't think even
> that's necessary if we can explain the behaviour properly in the docs.

In order to do the proper explanation, it seems to me we need to be clear on
three things:

1) Stacking priority depends on outside-staff-priority if it's present
2) If not, it depends on script-priority
3) How to decide if objects have an outside-staff-priority or a
script-priority, and what the value of those priorities is, so we can
intelligently override things where it's needed.

I'm clear on 1) and 2).  But I'm not clear on 3).

In the NR, I can find 1.3.1 Articulations and ornamentations, which appear
to be Script or TextScript objects (I'm not sure how to decide which -- both
are cross-referenced to the IR).

In the IR, Scripts have neither a staff-priority nor an
outside-staff-priority listed.  But it does list the grob-interface, which
has outside-staff-priority property.

Also in the IR, TextScripts have outside-staff-priority of 450 and
script-priority of 200.

So \turn must not be a TextScript, and I can't see (from the documentation)
that either priority is set for Script objects.

Can you help me figure out where to learn more about this?

Thanks,

Carl