Re: Different start and end bars

[Mats Bengtsson]

I'm afraid you'll have to take a look at the implementation to
be able to handle this problem. The bar lines to be printed at
line breaks is determined by the function specified by the
break-glyph-function property of the BarLine object.
In the following example, I have started from the default definition
(from scm/output-lib.scm and scm/lily.scm) and modified the
behaviour of ":|" to print a bar line also at the beginning of the
next line.

#(define (index-cell cell dir)
  (if (equal? dir 1)
      (cdr cell)
      (car cell)))

#(define (my-break-barline glyph dir)
   (let ((result (assoc glyph
                        '((":|:" . (":|" . "|:"))
                          ("||:" . ("||" . "|:"))
                          ("|" . ("|" . ()))
                          ("||:" . ("||" . "|:"))
                          ("|s" . (() . "|"))
                          ("|:" . ("|" . "|:"))
                          ("|." . ("|." . ()))
                           (".|" . ("|" . ".|"))
                          (":|" . (":|" . "|"))
                          ("||" . ("||" . ()))
                          (".|." . (".|." . ()))
                          ("" . ("" . ""))
                          (":" . (":" . ""))
                          ("empty" . (() . ()))
                          ("brace" . (() . "brace"))
                          ("bracket" . (() . "bracket"))
                          )
                        )))
     (if (equal? result #f)
         (ly:warn (string-append "Unknown bar glyph: `" glyph "'"))
         (index-cell (cdr result) dir))
     ) )

startBar = \notes { \once \override Staff.BarLine 
#'before-line-breaking-callback = ##f \bar "|" }
\score {

\new Staff \with { \remove "Clef_engraver" } {
\override Score.BarLine #'break-glyph-function = #my-break-barline
\override Score.TimeSignature #'break-visibility = #end-of-line-invisible

\notes {

\startBar
\time 4/4 f' a' c'' e'' \bar "|"
\time 4/4 f' a' c'' e'' \bar "|"
\time 4/4 f' a' c'' e'' \bar "|"
\time 4/4 f' a' c'' e'' \bar ":|" \break
\time 4/4 f' a' c'' e'' \bar "|"
\time 4/4 f' a' c'' e'' \bar "|"
\time 4/4 f' a' c'' e'' \bar "|"
\time 4/4 f' a' c'' e'' \bar ":|" \break
}}}


  /Mats

Ted Frazier wrote:
> Lilypond is wonderful and fun but until I understand the object model 
> can be frustrating...!!!
>  
> I am transcribing exercises and want behavior that is not standard. 
> Liliypond, with it's smarts, will start a new line of music with no bar 
> or the same bar that ended the previous line. I want to end every line 
> of music with a :| bar and start every line with a | bar. Take the 
> following code:
> startBar = \notes { \once \override Staff.BarLine 
> #'before-line-breaking-callback = ##f \bar "|" }
> \score {
>
> \new Staff \with { \remove "Clef_engraver" } {
>
> \override Score.TimeSignature #'break-visibility = #end-of-line-invisible
>
> \notes {
>
> \startBar
> \time 4/4 f' a' c'' e'' \bar "|"
> \time 4/4 f' a' c'' e'' \bar "|"
> \time 4/4 f' a' c'' e'' \bar "|"
> \time 4/4 f' a' c'' e'' \bar ":|" \break
>
> \startBar
> \time 4/4 f' a' c'' e'' \bar "|"
> \time 4/4 f' a' c'' e'' \bar "|"
> \time 4/4 f' a' c'' e'' \bar "|"
> \time 4/4 f' a' c'' e'' \bar ":|" \break
> }}}
>
> The first line of music ends with | and not :| as one might think. But 
> if I comment out the second \startBar command, the first line ends with 
> :| and the second line has no start bar. I have tried many ways of 
> getting around this and finally found one where I change the glyph in 
> the overridden BarLine print function by changing the glyph at hard 
> coded indices.
>  
> There's got to be a better way. Any ideas? Thanks...
>  
> Ted Frazier
>  
>
>
> ------------------------------------------------------------------------
>
> _______________________________________________
> lilypond-user mailing list
> address@hidden
> http://lists.gnu.org/mailman/listinfo/lilypond-user

--
=============================================
        Mats Bengtsson
        Signal Processing
        Signals, Sensors and Systems
        Royal Institute of Technology
        SE-100 44  STOCKHOLM
        Sweden
        Phone: (+46) 8 790 8463                         
        Fax:   (+46) 8 790 7260
        Email: address@hidden
        WWW: http://www.s3.kth.se/~mabe
=============================================