Re: Stencil questions (adding text and defining line style)

[David Nalesnik]

Hi Urs,

On Wed, Sep 21, 2016 at 1:49 PM, Urs Liska <address@hidden> wrote:
> Hi all,
>
> it may seem unprobable but I don't find the information how I can add
> some text to my constum-made stencils.
>
> Concretely I want to add a text element at a certain position to a
>   (ly:stencil-add
> construction

You would probably create the text stencil using grob-interpret-markup.
.
>
> The other thing I didn't find is: how can I create a dashed (or
> otherwise styled) line stencil with make-line-stencil?

You should use ly:line-interface::line (which is available from
2.19.27, off the top of my head).

Here's an example with both text and different line styles.

(Even though TextScript doesn't support line-interface, you can still
tweak line-related properties!)

\version "2.19.46"

#(define (my-stencil grob)
   (let* ((line (ly:line-interface::line grob 1.5 0 6 0))
          (text (grob-interpret-markup grob "A"))
          (stil (apply ly:stencil-add (list line text))))
     stil))

{
  \override TextScript.stencil = #my-stencil
  c''1 -\tweak style #'dashed-line ^""
  c''1 -\tweak style #'zigzag ^""
}

>
> More generally: how can I learn more about these things? Searching
> lilypond.org seems to only point to snippets and no real explanations.

There's not much to go on.

grob-interpret-markup is mentioned here:
http://lilypond.org/doc/v2.19/Documentation/extending/callback-functions

The function doesn't have a docstring:

#(display (procedure-documentation grob-interpret-markup))

returns #f ...

ly:line-interface::line is listed in the IR (Scheme functions)

Sorry I can't be more helpful.

David