Re: Help with Scheme engraver please

[Trevor Daniels]

----- Original Message ----- 
From: "Thomas Morley" <address@hidden>
To: "Trevor Daniels" <address@hidden>
Cc: "Lily-Devel List" <address@hidden>
Sent: Sunday, September 04, 2016 7:28 AM
Subject: Re: Help with Scheme engraver please


> 2016-09-03 19:29 GMT+02:00 Thomas Morley <address@hidden>:
> 
>> I've put some work on it. See attached duration-as-markup-5b-harm.ly
>> The general work should be clear from comments and descriptions.
>> There's some ugly code in it, although it works so far, wide room for
>> improvements still there.
>> Nevertheless it works now even in polyphonic.
> 
> Please replace the coding in `stop-translation-timestep' with:
> 
[snip]
>
> This will cure a bug with last notes starting at some moment, but with
> different durations.

Thanks  Harm, for this and the preceding mail.  I've found them very
helpful.  In particular, a simpler way to set stringTuning and how to set
persistent variables within engravers.  But I don't understand why you
used a rather complicated procedure to obtain durations.  Could you
not simply extract the durations from note events?

Actually I'd got quite a bit further than the simple example I posted,
and my current state is attached, extracting durations and pitches
from note-events, and detecting the start of bars by acknowledging
barline grobs.  This version draws duration grobs whenever the
duration changes, and at the start of every bar, bass course
grobs below the tab, adds fingering and laissez vibrer slurs (I think
that's what they are used for.)

There's quite a lot still wrong with this example, although it works in
simple cases.  You can see these problems listed in the TODOs.
And the code needs some tidying up too as bits of it are rather
messy (to say the least!).  And it would probably be better to separate
the generation of the two types of grobs into two engravers.

You'll see I use the Fronimo glyphs for the bass course indications,
and mensural flags for the durations.  These are just for demonstration: 
we'd need a set of lute tab glyphs of our own to be defined at some stage.

But this is now pretty close to Phase I which I defined in the note 
dated 22 Nov 2009, in this thread:
http://lilypond-s-support-for-tablatures.3383434.n2.nabble.com/Baroque-lute-tablature-td4008032.html

I probably will be somewhat unresponsive for 10 days or so, as we
are away on a belated summer break next week.

Trevor

duration-as-markup-11b.ly
Description: Text Data