On 28/05/2020 23:15, Valentin Villenave wrote:
On 5/28/20, Matt Wallis <[email protected]> wrote:
The output from event-listener is so close. I just need to get it to
listen to the appropriate events ... if that is possible.
Then you should definitely have a look at the last link I sent
(lilypond-html-video); IIRC it uses a Scheme engraver (so no patching
Lily itself) to output svg with additional timing information encoded
as data- attributes for each rhythmic event. Then one can use that to
get a cursor, change CSS attributes on the fly (e.g. noteheads
opacity), switch from one page to the next, etc. It’s still very much
WIP, but you can have a look at the examples (particularly the
vibraphone one) to get an idea.
Many thanks for the pointer. I had not encountered lilypond-html-video
before.
It is very informative to see how the Grob_metadata_engraver is
constructed in
https://gitlab.com/sigmate/lilypond-html-live-score/-/blob/master/grob-inspector.ily.
I finally have a reason to look into what a grob is - did I mention I
was new to this? :-)
But it is working on a single SVG (one long line) using
one-line-auto-height-page-breaking, whereas I want a sequence of pages,
and to know when each page starts (in seconds).
From my initial reading, I suspect there is a way of inferring from the
grobs when a new page begins. I find myself asking: if I have one System
per page, can I infer a page has started by acknowledging all System
grobs?.
But I would rather do this more directly by listening to the
page-break-event (or something like that).
I’m CCing Mathieu as it’s his project. Mathieu, you can read Matt’s
previous message here:
https://lists.gnu.org/archive/html/lilypond-user/2020-05/msg00527.html
And my original question is here:
https://lists.gnu.org/archive/html/lilypond-user/2020-05/msg00521.html
BTW, I didn't see a vibraphone example. I scanned a few branches, but
maybe I didn't try the right branch.
All the best, Matt
