Re: outside-staff-priority with slur and hairpin

[Jonathan Wilkes]

--- On Fri, 9/18/09, Trevor Daniels <address@hidden> wrote:

> From: Trevor Daniels <address@hidden>
> Subject: Re: outside-staff-priority with slur and hairpin
> To: "Jonathan Wilkes" <address@hidden>, address@hidden
> Date: Friday, September 18, 2009, 10:22 AM
> 
> Jonathan Wilkes wrote Friday, September 18, 2009 6:51 AM
> 
> > --- On Thu, 9/17/09, Trevor Daniels <address@hidden>
> wrote:
> >> 
> >> Have you not read the Learning Manual? The
> >> Notation Reference assumes you have. This is
> >> explained in considerable detail in section
> 4.4.3.
> > 
> > Sorry, I wasn't very clear.  I wanted to know why
> I can't just set
> > Hairpin to #1 and the Slur to #2 for
> 'outside-staff-priority.  And I
> > forgot to search the LM before posting.
> > 
> > Yes, I've read (but not memorized) the LM, and I see
> that overriding the 'outside-staff-priority for
> DynamicLineSpanner works > while using
> > the same override for Hairpin does not.  Yet
> nothing in the section you
> > refer to states that DynamicLineSpanner is the *only*
> way to change
> > 'outside-staff-priority for a dynamic.
> 
> You make a valid point here.  One one hand it should
> be obvious that
> you have to change the property in the correct object, but
> OTOH it is
> not obvious what the correct object is when spanners are
> involved.
> This is mentioned in the LM, but at some distance from the
> section on
> grobs and interfaces.  At the end of 4.5.1 there's a
> table of object
> names that need to be tweaked to move various objects,
> including
> dynamics.  I'll add a forward reference to that.
> 
> Perhaps there should also be a gentle introduction to
> spanners in the LM.
> These are discussed in the Notation Reference (section
> 5.4.6), but that
> is a little fierce for starters.  I'll think about
> that.
> 
> > There's a paragraph in LM 4.3.1 that says [regarding
> properties of
> > objects]:
> > 
> > "Before we tackle this, let us remember that object
> properties are grouped in what are called interfaces – see
> Properties
> > found in interfaces. This is simply to group together
> those properties that may be used together to tweak a
> graphical object  > – if one of them is allowed
> for an object, so are the others. Some objects then use the
> properties in some interfaces, others > use them from
> other interfaces. The interfaces which contain the
> properties used by a particular grob are listed in the IR
> at
> > the bottom of the page describing that grob, and those
> properties may be viewed by looking at those interfaces."
> > 
> > So when it says properties are "allowed" for an
> object, what exactly does
> > that mean?  Also, what does it mean to say "the
> properties used by a
> > particular grob?"
> > 
> > I'm not a programmer, so some of this is a little
> difficult to grasp, but
> > by the logic of that paragraph what I'm getting is
> that
> > 'outside-staff-priority is a property that is allowed
> for Hairpin objects
> > (because I know 'transparent works on Hairpins and is
> part of the grob
> > interface), is used by Hairpin objects (because
> grob-interface is listed
> > at the bottom of the IR for Hairpin), but still cannot
> be used to
> > make the Hairpin go below the Slur in my example.
> 
> This is not easily explained.  An object has -access-
> to all the properties
> listed in the interfaces it supports, but it does not
> necessarily honor them.
> 
> The difficulty is that there is no general rule that can be
> used to discover
> which properties have an effect on a particular grob and
> which do not.
> In this case one has to know that hairpins are spanners
> (because they
> start and end at different musical moments), and spanners
> are positioned
> by the appropriate spanner object.

I think this is the most difficult part of using Lilypond that I've 
come up against.  Currently I'm using the IR as a kind of "quick 
reference" manual- if I need to tweak something like how long a hairpin 
should be, I just go to Hairpin and find what seems like the right 
property.  But as your explanation (and others on this list) point to, there's 
a lot more to take into consideration to get the right 
property (e.g., 'font-size vs. 'zigzag-width for the width of the trill 
continuation glyph).

-Jonathan

> 
> Thanks for your comments - they are what I need to help me
> to understand
> how the LM might be improved.
> 
> Trevor
> 
>