Re: Has anything been done about implementing music streams?

[Carl Sorensen]

On 1/25/11 7:34 AM, "Bernard Hurley" <address@hidden> wrote:

> Hi,
> 
> On Sun, 2011-01-23 at 06:36 -0700, Carl Sorensen wrote:
>> On 1/23/11 6:22 AM, "Bernard Hurley" <address@hidden> wrote:
>> 
>>> Hi,
>>> 
>>> In order to understand the lily code better I read Erik Sandberg¹s
>>> master's thesis. The idea of a music stream seems very interesting. Is
>>> this anywhere near being implemented?
>> 
>> Yes, music streams are currently implemented in LilyPond.
>> 
>> You will see Stream_event listed in the C++ code.
>> 
> 
> Thanks, but if the ideas in Erik's thesis were completely implemented
> then the music stream should be an intermediate representation of the
> music that could be exported from lily. I can't see any command line
> options for this nor can I see anything in the code that would allow
> this to be done. If it is there where is it hiding?

Well, the dispatchers are implemented in lily/dispatcher.cc,
lily/dispatcher-scheme.cc, and lily/include/dispatcher.hh, as well as all
the iterators.

git grep dispatcher will show you all of this information.

The methods to save music streams to disk and to load music streams to disk
have not been made command options for lilypond.  In Erik's words, this
would use "alternative front- and back-ends, which substitute the defaults."

The alternative front end and alternative back end are not currently
implemented, as far as I can see.  According to section 7.3 of the thesis,
all that is necessary can be accomplished in a .ly file.  Note that he says

"• A LY file has been written, which makes LilyPond output the music stream
that corresponds to an arbitrary music expression. Appendix C and Appendix D
contain examples of music streams created using this LY file.

• A LY file has been written, which makes LilyPond read a music stream as
input, and produce a corresponding PDF file.
"

But I have no knowledge of these .ly files, and how one might get a copy of
them.  Han-Wen was his thesis supervisor, and may have copies, or know how
we might get them.

HTH,

Carl