Re: Issue 1691 in lilypond: Ugly bars in PDF documents

[lilypond]

Comment #26 on issue 1691 by address@hidden: Ugly bars in PDF  
documents
http://code.google.com/p/lilypond/issues/detail?id=1691

OK.  Further updates.  I started my testing today using this:

@lilypond[fragment]
\repeat unfold 100 { c'4 }
@end lilypond

I now realise that this is generally not used for the docs, but hadn't  
caught on earlier.  It produces a lily source file with this paper block:

\paper {
  indent = 0\mm
  line-width = #(- paper-width left-margin-default right-margin-default )
  ragged-right = ##t
  force-assignment = #""
  line-width = #(- line-width (* mm  3.000000))
}

Note the lack of numeric varibles in the line-width.  This produces a  
snippet of a normal size for output to PDF, but much too wide for the docs  
- it goes way over the right of the page.  Note also the minor reduction in  
width - it looks to me like the bottom line takes 3mm off the line width,  
for some reason.  It's set in the definition PREAMBLE_LY =

I then looked at

@lilypond[verbatim,quote]
\repeat unfold 100 { c'4 }
@end lilypond

This gives us this paper block:

\paper {
  indent = 0\mm
  line-width = 160\mm - 2.0 * 0.4\in
  force-assignment = #""
  line-width = #(- line-width (* mm  3.000000))
}

which comes from the line:

QUOTE: r'''line-width = %(line-width)s - 2.0 * %(exampleindent)s''',

This gives black bars, but is only just too wide.

which is not reset to the value above, since that's only done if the  
snippet is not quoted.  Following the earlier work testing which line-width  
I tried:

@lilypond[verbatim,quote,line-width=15.5\cm]
\repeat unfold 100 { c'4 }
@end lilypond

which gives the paper block:

\paper {
  indent = 0\mm
  line-width = 15.5\cm
  line-width = 15.5\cm - 2.0 * 0.4\in
  force-assignment = #""
  line-width = #(- line-width (* mm  3.000000))
}

which gives no black bars.  I now understand this quite a bit better, and  
you were clearly quite right about my previous suggestion!  I think the  
mechanism of reducing the line width of quoted snippets by 2 times the  
indent takes off _just_ too little width - if we replace 2 * exampleindent  
with 2.05 *, the problem is again solved for these snippets.