Re: [Lilypond-auto] Issue 2542 in lilypond: Support for pdf layers

[lilypond]

Comment #1 on issue 2542 by address@hidden: Support for pdf layers
http://code.google.com/p/lilypond/issues/detail?id=2542

Maybe it would be useful to start with a basic support for outputting to  
pdf layers without bothering with all the complex layout considerations.

The support for a layer that is as independent as a default layer in a  
layout program can be of immediate use.
To name just two potential uses that I can directly see:
- if the output of annotate-spacing were written on a separate layer, the  
end user could simply switch the display of it on and off without  
recompiling the score, making it easier to compare.
- the same would be useful for things like the visualization of bezier  
control-points that was realized in this thread:  
http://lists.gnu.org/archive/html/bug-lilypond/2012-05/msg00011.html.

Maybe one could implement a basic (but clean) support for this and could  
only later develop the more complex implications (like output that implies  
collision handling in other layers)?