Re: Changing autobeaming for 4/4 time

[Trevor Daniels]

Carl Sorensen wrote Sunday, August 09, 2009 10:59 PM

> Could the two of you please take some of these examples and beam 
> them
> manually so that I can see what they *should* do?  I'll then try 
> to figure
> out why the autobeam engraver doesn't do it.
>
> Some explanation as to *why* it should work the way it should 
> would also be
> helpful.

There is no fixed rule for beaming in 4/4.
Beams ending at 1/2 are often used, as are
beams ending at 1/4, 1/2 and 3/4.  Whichever
is chosen, the beaming must be consistent
throughout the bar.  There are two issues:

a) the default beaming rules are not optimum, and

b) it is not possible to find beaming rules that
beam certain groupings consistently.  The
following examples illustrate the problems.

\relative c'' {
 a8 a a a a a a a |  % OK

 a16 a a8 a a
 a a16 a a8 a |  % wrong, should be ...
 a16[ a a8] a a
 a[ a16 a] a8 a |

 a8 a a16 a a8
 a a a a16 a | % wrong, should be ...
 a8 a a16[ a a8]
 a a a[ a16 a] |

 a8 a16 a a8 a16 a
 a8 a16 a a8 a16 a | % wrong, should be ...
 a8[ a16 a] a8 a16 a
 a8[ a16 a] a8 a16 a |

 a32 a a16 a a a a32 a a16 a
 a a a32 a a16 a a a a32 a | % wrong, should be ...
 a32[ a a16 a a] a[ a32 a a16 a]
 a[ a a32 a a16] a a a a32 a
}

Trevor