@c -*- coding: utf-8; mode: texinfo; -*-
+@c This file is part of lilypond.tely
+@ignore
+ Translation of GIT committish: FILL-IN-HEAD-COMMITTISH
+
+ When revising a translation, copy the HEAD committish of the
+ version that you are working on. See TRANSLATION for details.
+@end ignore
+
@node Working on LilyPond projects
@chapter Working on LilyPond projects
This section explains a how to solve or avoid certain common
problems. If you have programming experience, many of these
-tips may seem obvious; you may wish to simply skim this
-chapter.
+tips may seem obvious, but it is still advisable to read
+this chapter.
@menu
* Suggestions for writing LilyPond files::
+* Saving typing with identifiers and functions::
+* Style sheets::
+* Updating old files::
* Troubleshooting (taking it all apart)::
-* Saving typing with identifiers::
@end menu
little examples in the tutorial, but whole pieces. But how should you
go about doing it?
-The best answer is ``however you want to do it.'' As long as LilyPond
-can understand your files and produces the output that you want, it
-doesn't matter what your files look like. That said, sometimes we
-make mistakes when writing files. If LilyPond can't understand your
-files, or produces output that you don't like, how do you fix the
-problem?
+As long as LilyPond can understand your files and produces the output
+that you want, it doesn't matter what your files look like. However,
+there are a few other things to consider when writing lilypond files.
+
+@itemize @bullet
+@item What if you make a mistake? The structure of a lilypond
+file can make certain errors easier (or harder) to find.
+
+@item What if you want to share your files with somebody
+else? In fact, what if you want to alter your own files in
+a few years? Some lilypond files are understandable at
+first glance; other files may leave you scratching your head
+for an hour.
+
+@item What if you want to upgrade your lilypond file for use
+with a later version of lilypond? The input syntax changes
+occasionally as lilypond improves. Most changes can be
+done automatically with @code{convert-ly}, but some changes
+might require manual assistance. Lilypond files can be
+structured in order to be easier (or header) to update.
+@end itemize
+
+@menu
+* General suggestions::
+* Typesetting existing music::
+* Large projects::
+@end menu
+
+
+@node General suggestions
+@subsection General suggestions
Here are a few suggestions that can help you to avoid or fix
problems:
@itemize @bullet
@item @strong{Include @code{\version} numbers in every file}. Note that all
-templates contain a @code{\version "2.8.0"} string. We
+templates contain a @code{\version "2.9.13"} string. We
highly recommend that you always include the @code{\version}, no matter
how small your file is. Speaking from personal experience, it's
quite frustrating to try to remember which version of LilyPond you were
using a few years ago. @code{convert-ly} requires you to declare
which version of LilyPond you used.
-@item @strong{Include checks}: @ref{Bar check}s and @ref{Octave check}s. If you
+@item @strong{Include checks}: @ref{Bar check} and @ref{Octave check}. If
+you
include checks every so often, then if you make a mistake, you can pinpoint
-it quicker. How often is ``every so often''? It depends on the complexity
+it quicker. How often is @q{every so often}? It depends on the complexity
of the music. For very simple music, perhaps just once or twice. For
very complex music, perhaps every bar.
-@item @strong{One bar per line of text}. If there is anything complicated, either in the music
+@item @strong{One bar per line of text}. If there is anything complicated,
+either in the music
itself or in the output you desire, it's often good to write only one bar
per line. Saving screen space by cramming eight bars per line just isn't
-worth it if you have to `debug' your files.
+worth it if you have to @q{debug} your files.
+
+@item @strong{Comment your files}. Use either bar numbers (every so often)
+or
+references to musical themes (@q{second theme in violins,} @q{fourth
+variation,} etc.). You may not need comments when you're writing the piece
+for the first time, but if you want to go back to change something two or
+three years later, or if you pass the source over to a friend, it will
+be much more
+challenging to determine your intentions or how your file is structured if
+you didn't comment the file.
+
+@item @strong{Indent your braces}. A lot of problems are caused by an
+imbalance
+in the number of @code{@{} and @code{@}}.
-@item @strong{Comment your files}, with either bar numbers (every so often) or
-references to musical themes (``second theme in violins'', ``fourth
-variation''). You may not need it when you're writing the piece for
-the first time, but if you want to go back and change something two
-or three years later, you won't know how your file is structured if you
-didn't comment the file.
+@item @strong{Explicity add durations} at the beginnings of sections
+and identifiers. If you specify @code{c4 d e} at the beginning of a
+phrase (instead of just @code{c d e}) you can save yourself some
+problems if you rearrange your music later.
-@item @strong{Indent your braces}. A lot of problems are caused by an imbalance
-in the number of @code{@{} and @code{@}}.
+@item @strong{Separate tweaks} from music definitions. See
+@ref{Saving typing with identifiers and functions} and
+@ref{Style sheets}.
@end itemize
+@node Typesetting existing music
+@subsection Typesetting existing music
-
-If you are entering music from an existing score (i.e. typesetting a
+If you are entering music from an existing score (i.e., typesetting a
piece of existing sheet music),
@itemize @bullet
@end itemize
-@node Troubleshooting (taking it all apart)
-@section Troubleshooting (taking it all apart)
+@node Large projects
+@subsection Large projects
-Sooner or later, you will write a file that LilyPond cannot
-compile. The messages that LilyPond gives may help
-you find the error, but in many cases you need to do some
-investigation to determine the source of the problem.
+When working on a large project, having a clear structure to your
+lilypond files becomes vital.
-The most powerful tools for this purpose are the
-single line comment (indicated by @code{%}) and the block
-comment (indicated by @code{%@{ ... %@}}). If you don't
-know where a problem is, start commenting out huge portions
-of your input file. After you comment out a section, try
-compiling the file again. If it works, then the problem
-must exist in the portion you just commented. If it doesn't
-work, then keep on commenting out material until you have
-something that works.
+@itemize @bullet
-In an extreme case, you might end up with only
+@item @strong{Use an identifier for each voice}, with a minimum of
+structure inside the definition. The structure of the
+@code{\score} section is the most likely thing to change;
+the @code{violin} definition is extremely unlikely to change
+in a new version of LilyPond.
@example
+violin = \relative c'' @{
+g4 c'8. e16
+@}
+...
\score @{
- <<
- % \melody
- % \harmony
- % \bass
- >>
- \layout@{@}
+ \new GrandStaff @{
+ \new Staff @{
+ \violin
+ @}
+ @}
@}
@end example
-@noindent
-(in other words, a file without any music)
-
-If that happens, don't give up. Uncomment a bit -- say,
-the bass part -- and see if it works. If it doesn't work,
-then comment out all of the bass music (but leave
-@code{\bass} in the @code{\score} uncommented.
+@item @strong{Separate tweaks from music definitions}. This
+point was made in @ref{General suggestions}, but for large
+projects it is absolutely vital. We might need to change
+the definition of @code{fthenp}, but then we only need
+to do this once, and we can still avoid touching anything
+inside @code{violin}.
@example
-bass = \relative c' @{
-%@{
- c4 c c c
- d d d d
-%@}
+fthenp = _\markup@{
+ \dynamic f \italic \small @{ 2nd @} \hspace #0.1 \dynamic p @}
+violin = \relative c'' @{
+g4\fthenp c'8. e16
@}
@end example
-Now start slowly uncommenting more and more of the
-@code{bass} part until you find the problem line.
+@end itemize
-@node Saving typing with identifiers
-@section Saving typing with identifiers
+@node Saving typing with identifiers and functions
+@section Saving typing with identifiers and functions
+
+@cindex variables
+@cindex identifiers
By this point, you've seen this kind of thing:
violin = \relative c'' @{
\repeat volta 2 @{
c4._\markup@{ \italic \bold dolce @} b8 a8 g a b |
- \once \override TextScript #'padding = #5.0
+ \once \override TextScript #'padding = #5.0
c4.^"hi there!" d8 e' f g d |
c,4.\markup@{ \dynamic f \italic \small @{ 2nd @}
\hspace #0.1 \dynamic p @} b8 c4 c-. |
@lilypond[quote,verbatim,ragged-right]
padText =
#(define-music-function (parser location padding) (number?)
- #{
+ #{
\once \override TextScript #'padding = #$padding
- #})
+ #})
\relative c''' {
c4^"piu mosso" b a b
}
@end lilypond
+Using identifiers is also a good way to reduce work if the
+LilyPond input syntax changes (see @ref{Updating old files}). If
+you have a single definition (such as @code{\dolce}) for all your
+files (see @ref{Style sheets}), then if the syntax changes, you
+only need to update your single @code{\dolce} definition,
+instead of making changes throughout every @code{.ly} file.
+
+
+@node Style sheets
+@section Style sheets
+
+The output that LilyPond produces can be heavily modified; see
+@ref{Tweaking output} for details. But what if you have many
+files that you want to apply your tweaks to? Or what if you
+simply want to separate your tweaks from the actual music? This
+is quite easy to do.
+
+Let's look at an example. Don't worry if you don't understand
+the parts with all the #(). This is explained in
+@ref{Advanced tweaks with Scheme}.
+
+@lilypond[quote,verbatim,ragged-right]
+mpdolce = #(make-dynamic-script (markup #:hspace 1 #:translate (cons 5 0)
+ #:line(#:dynamic "mp" #:text #:italic "dolce" )))
+tempoMark = #(define-music-function (parser location markp) (string?)
+#{
+ \once \override Score . RehearsalMark #'self-alignment-X = #left
+ \once \override Score . RehearsalMark #'extra-spacing-width = #'(+inf.0 . -inf.0)
+ \mark \markup { \bold $markp }
+#})
+
+\relative c'' {
+ \tempo 4=50
+ a4.\mpdolce d8 cis4--\glissando a | b4 bes a2
+ \tempoMark "Poco piu mosso"
+ cis4.\< d8 e4 fis | g8(\! fis)-. e( d)-. cis2
+}
+@end lilypond
+
+There are some problems with overlapping output; we'll fix those using
+the techniques in @ref{Moving objects}. But let's also
+do something about the @code{mpdolce} and @code{tempoMark}
+definitions. They produce the output we desire, but we might want
+to use them in another piece. We could simply copy-and-paste them
+at the top of every file, but that's an annoyance. It also leaves
+those definitions in our music files, and I personally find all
+the #() somewhat ugly. Let's hide them in another file:
+
+@example
+%%% save this to a file called "definitions.ly"
+mpdolce = #(make-dynamic-script (markup #:hspace 1 #:translate (cons 5 0)
+ #:line(#:dynamic "mp" #:text #:italic "dolce" )))
+tempoMark = #(define-music-function (parser location markp) (string?)
+#@{
+ \once \override Score . RehearsalMark #'self-alignment-X = #left
+ \once \override Score . RehearsalMark #'extra-spacing-width = #'(+inf.0 . -inf.0)
+ \mark \markup @{ \bold $markp @}
+#@})
+@end example
+
+Now let's modify our music (let's save this file as @file{"music.ly"}).
+
+@c We have to do this awkward example/lilypond-non-verbatim
+@c because we can't do the \include stuff in the manual.
+
+@example
+\include "definitions.ly"
+
+\relative c'' @{
+ \tempo 4=50
+ a4.\mpdolce d8 cis4--\glissando a | b4 bes a2
+ \once \override Score.RehearsalMark #'padding = #2.0
+ \tempoMark "Poco piu mosso"
+ cis4.\< d8 e4 fis | g8(\! fis)-. e( d)-. cis2
+@}
+@end example
+
+@lilypond[quote,ragged-right]
+mpdolce = #(make-dynamic-script (markup #:hspace 1 #:translate (cons 5 0)
+ #:line(#:dynamic "mp" #:text #:italic "dolce" )))
+tempoMark = #(define-music-function (parser location markp) (string?)
+#{
+ \once \override Score . RehearsalMark #'self-alignment-X = #left
+ \once \override Score . RehearsalMark #'extra-spacing-width = #'(+inf.0 . -inf.0)
+ \mark \markup { \bold $markp }
+#})
+
+\relative c'' {
+ \tempo 4=50
+ a4.\mpdolce d8 cis4--\glissando a | b4 bes a2
+ \once \override Score.RehearsalMark #'padding = #2.0
+ \tempoMark "Poco piu mosso"
+ cis4.\< d8 e4 fis | g8(\! fis)-. e( d)-. cis2
+}
+@end lilypond
+
+That looks better, but let's make a few changes. The glissando is hard
+to see, so let's make it thicker and closer to the noteheads. Let's
+put the metronome marking above the clef, instead of over the first
+note. And finally, my composition professor hates "C" time signatures,
+so we'd better make that "4/4" instead.
+
+Don't change @file{music.ly}, though. Replace our @file{definitions.ly}
+with this:
+
+@example
+%%% definitions.ly
+mpdolce = #(make-dynamic-script (markup #:hspace 1 #:translate (cons 5 0)
+ #:line( #:dynamic "mp" #:text #:italic "dolce" )))
+tempoMark = #(define-music-function (parser location markp) (string?)
+#@{
+ \once \override Score . RehearsalMark #'self-alignment-X = #left
+ \once \override Score . RehearsalMark #'extra-spacing-width = #'(+inf.0 . -inf.0)
+ \mark \markup @{ \bold $markp @}
+#@})
+
+\layout@{
+ \context @{ \Score
+ \override MetronomeMark #'extra-offset = #'(-9 . 0)
+ \override MetronomeMark #'padding = #'3
+ @}
+ \context @{ \Staff
+ \override TimeSignature #'style = #'numbered
+ @}
+ \context @{ \Voice
+ \override Glissando #'thickness = #3
+ \override Glissando #'gap = #0.1
+ @}
+@}
+@end example
+
+@lilypond[quote,ragged-right]
+mpdolce = #(make-dynamic-script (markup #:hspace 1 #:translate (cons 5 0)
+ #:line( #:dynamic "mp" #:text #:italic "dolce" )))
+tempoMark = #(define-music-function (parser location markp) (string?)
+#{
+ \once \override Score . RehearsalMark #'self-alignment-X = #left
+ \once \override Score . RehearsalMark #'extra-spacing-width = #'(+inf.0 . -inf.0)
+ \mark \markup { \bold $markp }
+#})
+
+\layout{
+ \context { \Score
+ \override MetronomeMark #'extra-offset = #'(-9 . 0)
+ \override MetronomeMark #'padding = #'3
+ }
+ \context { \Staff
+ \override TimeSignature #'style = #'numbered
+ }
+ \context { \Voice
+ \override Glissando #'thickness = #3
+ \override Glissando #'gap = #0.1
+ }
+}
+
+\relative c'' {
+ \tempo 4=50
+ a4.\mpdolce d8 cis4--\glissando a | b4 bes a2
+ \once \override Score.RehearsalMark #'padding = #2.0
+ \tempoMark "Poco piu mosso"
+ cis4.\< d8 e4 fis | g8(\! fis)-. e( d)-. cis2
+}
+@end lilypond
+
+That looks nicer! But now suppose that I want to publish this
+piece. My composition professor doesn't like "C" time
+signatures, but I'm somewhat fond of them. Let's copy the
+current @file{definitions.ly} to @file{web-publish.ly} and
+modify that. Since this music is aimed at producing a pdf which
+will be displayed on the screen, we'll also increase the
+overall size of the output.
+
+@example
+%%% definitions.ly
+mpdolce = #(make-dynamic-script (markup #:hspace 1 #:translate (cons 5 0)
+ #:line( #:dynamic "mp" #:text #:italic "dolce" )))
+tempoMark = #(define-music-function (parser location markp) (string?)
+#@{
+ \once \override Score . RehearsalMark #'self-alignment-X = #left
+ \once \override Score . RehearsalMark #'extra-spacing-width = #'(+inf.0 . -inf.0)
+ \mark \markup @{ \bold $markp @}
+#@})
+
+#(set-global-staff-size 23)
+\layout@{
+ \context @{ \Score
+ \override MetronomeMark #'extra-offset = #'(-9 . 0)
+ \override MetronomeMark #'padding = #'3
+ @}
+ \context @{ \Staff
+ @}
+ \context @{ \Voice
+ \override Glissando #'thickness = #3
+ \override Glissando #'gap = #0.1
+ @}
+@}
+@end example
+
+@lilypond[quote,ragged-right]
+mpdolce = #(make-dynamic-script (markup #:hspace 1 #:translate (cons 5 0)
+ #:line( #:dynamic "mp" #:text #:italic "dolce" )))
+tempoMark = #(define-music-function (parser location markp) (string?)
+#{
+ \once \override Score . RehearsalMark #'self-alignment-X = #left
+ \once \override Score . RehearsalMark #'extra-spacing-width = #'(+inf.0 . -inf.0)
+ \mark \markup { \bold $markp }
+#})
+
+#(set-global-staff-size 23)
+\layout{
+ \context { \Score
+ \override MetronomeMark #'extra-offset = #'(-9 . 0)
+ \override MetronomeMark #'padding = #'3
+ }
+ \context { \Voice
+ \override Glissando #'thickness = #3
+ \override Glissando #'gap = #0.1
+ }
+}
+
+\relative c'' {
+ \tempo 4=50
+ a4.\mpdolce d8 cis4--\glissando a | b4 bes a2
+ \once \override Score.RehearsalMark #'padding = #2.0
+ \tempoMark "Poco piu mosso"
+ cis4.\< d8 e4 fis | g8(\! fis)-. e( d)-. cis2
+}
+@end lilypond
+
+Now in our music, I simply replace
+@code{\include "definitions.ly"} with
+@code{\include "web-publish.ly"}. Of course, we could make this
+even more convenient. We could make a @file{definitions.ly} file which
+contains only the definitions of @code{mpdolce} and @code{tempoMark}, a
+@file{web-publish.ly} file which contains only the @code{\layout}
+section listed above, and a @file{university.ly} file which
+contains only the tweaks to produce the output that my professor
+prefers. The top of @file{music.ly} would then look like this:
+
+@example
+\include "definitions.ly"
+
+%%% Only uncomment one of these two lines!
+\include "web-publish.ly"
+%\include "university.ly"
+@end example
+
+This approach can be useful even if you are only producing
+one set of parts. I use half a dozen different
+@q{style sheet} files for my projects. I begin every music
+file with @code{\include "../global.ly"}, which contains
+
+@example
+%%% global.ly
+\version "2.9.13"
+#(ly:set-option 'point-and-click #f)
+\include "../init/init-defs.ly"
+\include "../init/init-layout.ly"
+\include "../init/init-headers.ly"
+\include "../init/init-paper.ly"
+@end example
+
+
+@node Updating old files
+@section Updating old files
+
+The LilyPond input syntax occasionally changes. As LilyPond itself
+improves, the syntax (input language) is modified accordingly. Sometimes
+these changes are made to make the input easier to read and write or
+sometimes the changes are made to accomodate new features of LilyPond.
+
+LilyPond comes with a file that makes this updating easier:
+@code{convert-ly}. For details about how to run this program, see
+@ref{Updating files with convert-ly}.
+
+Unforunately, @code{convert-ly} cannot handle all input changes. It
+takes care of simple search-and-replace changes (such as @code{raggedright}
+becoming @code{ragged-right}), but some changes are too
+complicated. The syntax changes that @code{convert-ly} cannot handle
+are listed in @ref{Updating files with convert-ly}.
+
+For example, in LilyPond 2.4 and earlier, accents and non-English
+letters were entered using LaTeX -- for example,
+@samp{No\"el} (this would print the French word for
+@q{Christmas}). In LilyPond 2.6 and above, the special
+@samp{ë} must be entered directly into the LilyPond file as an
+UTF-8 character. @code{convert-ly} cannot change all the LaTeX
+special characters into UTF-8 characters; you must manually update
+your old LilyPond files.
+
+
+@node Troubleshooting (taking it all apart)
+@section Troubleshooting (taking it all apart)
+
+Sooner or later, you will write a file that LilyPond cannot
+compile. The messages that LilyPond gives may help
+you find the error, but in many cases you need to do some
+investigation to determine the source of the problem.
+
+The most powerful tools for this purpose are the
+single line comment (indicated by @code{%}) and the block
+comment (indicated by @code{%@{ ... %@}}). If you don't
+know where a problem is, start commenting out huge portions
+of your input file. After you comment out a section, try
+compiling the file again. If it works, then the problem
+must exist in the portion you just commented. If it doesn't
+work, then keep on commenting out material until you have
+something that works.
+
+In an extreme case, you might end up with only
+
+@example
+\score @{
+ <<
+ % \melody
+ % \harmony
+ % \bass
+ >>
+ \layout@{@}
+@}
+@end example
+
+@noindent
+(in other words, a file without any music)
+
+If that happens, don't give up. Uncomment a bit -- say,
+the bass part -- and see if it works. If it doesn't work,
+then comment out all of the bass music (but leave
+@code{\bass} in the @code{\score} uncommented.
+
+@example
+bass = \relative c' @{
+%@{
+ c4 c c c
+ d d d d
+%@}
+@}
+@end example
+
+Now start slowly uncommenting more and more of the
+@code{bass} part until you find the problem line.
projects / lilypond.git / blobdiff