Re: Backend and non-backend (was Re: Stencil bounding box)

[Han-Wen Nienhuys]

David Feuer schreef:
> On 5/2/06, Han-Wen Nienhuys <address@hidden> wrote:
>
> > You're relying on specifics of music notation, eg. existence of ledger
> > lines and bar lines. What do you do when there are just lyrics or chord
> > names, or when there are no barlines (unmetered music) or no noteheads
> > (clusters).
> >
> > I think a more generic solution is called for.
>
> Okay.  I don't understand the whole grob thing yet, and that seems
> pretty key to writing this.  Where would the signature dumping code go
> exactly (what file/function)?  

for now, you can hook into

*  output-preview-framework  (framework-ps.scm)

This will usually give you only the 1st system (of the type: 
paper-system) of a score, but generalizing to multiple systems should be 
easy.

* output-framework (framework-ps.scm)

This is the function called in the default case.


You can get at the stencil of a stencil inside the paper-system with the 
paper-system-stencil function. The stencils have links to grobs 
(grob-cause expression), from where you can extract bboxes.


> The lining up thing was just an idea. I 
> don't know if it's even necessary.  Can I depend on the systems
> already being lined up properly with each other? 

What do you mean by lined up?

> That would certainly
> make things easier.  Also, I've been assuming that the grobs might
> come out in different orders in the two versions.  Is that more
> general than necessary?

no.


--

Han-Wen Nienhuys - address@hidden - http://www.xs4all.nl/~hanwen

LilyPond Software Design
 -- Code for Music Notation
http://www.lilypond-design.com