Re: Beam collision engraver in lilypond

[address@hidden]

On Feb 9, 2011, at 12:56 PM, Han-Wen Nienhuys wrote:

> On Wed, Feb 9, 2011 at 7:15 AM, address@hidden
> <address@hidden> wrote:
>> Hey all,
>> I just git pull'd the source and found beam collision engraver in lilypond.
>> A couple things:
>> [snip]
> 
> I'll try to do this today.   Did I break the regtests?
> 
>> 2)  I saw that a bar line acknowledger was added to the engraver.  I feel
>> that this should be removed; in most scores, beams that cross bar lines
>> collide with the bar line.  See http://www.youtube.com/watch?v=7hEifT_Zy7E ,
> 
> It looked odd to my eye in a regtest I added; is this universal
> practice, or should it be tunable?
> 

I like the tunable idea.

Perhaps a grob property named `avoids' that is a list of pairs, kinda like:

'((bar-line . #t) (time-signature . #f) (note-head . #t)) etc...

Then, we could use has_interface to weed out grobs for which we don't want to 
collision detect.

As to your question: in scores by Ligeti, Bartok, and Schoenberg, and Xenakis, 
bar lines are not avoided.  I cannot come up with an example off the top of my 
head where bar lines are avoided.

Cheers,
MS