LilyPond — 学习手册

附录

1 教程

这一章是使用 LilyPond 的基本介绍.

1.1 编译文件

这一节介绍了 “编译”—处理你写的 LilyPond 输入文件从而生成输出文件.

1.1.1 进行输入

“编译” 说的是处理 LilyPond 格式的输入文件从而生成输出文件的过程。输出文件 一般是 PDF 格式（用于打印或直接浏览）、MIDI 格式（用于演奏）、或 PNG 格式（用于在线使用）。LilyPond 的输入文件就是简单的文本文件。

这个例子展示了一个简单的输入文件：

\version "2.23.3"
{
  c' e' g' e'
}

图形输出为：

此外，LilyPond 的输入是 大小写敏感的。 ‘{ c d e }’ is 有效输入；‘{ C D E }’ 会报错。

生成输出

生成输出文件的方法取决于你电脑的操作系统和你使用的程序。

• MacOS X (图形化界面)
• Microsoft Windows (图形化界面)
• @ref{Command-line, @image{pictures/logo-linux,,,logo-linux} @image{pictures/logo-freebsd,,,logo-freebsd} @image{pictures/logo-macosx,,,logo-macosx} @image{pictures/logo-windows,,,logo-windows} } @ref{Command-line, 任何操作系统} (命令提示行)

有很多其他的文本编辑器提供对 LilyPond 特定的支持。更多信息，见 Easier editing.

1.1.2 MacOS X

Step 1. Create your ‘.ly’ file

Double click the LilyPond.app, an example file will open.

From the menus along the top left of your screen, select File > Save.

Choose a name for your file, for example ‘test.ly’.

Step 2. Compile (with LilyPad)

From the same menus, select Compile > Typeset.

A new window will open showing a progress log of the compilation of the file you have just saved.

Step 3. View output

Once the compilation has finished, a PDF file will be created with the same name as the original file and will be automatically opened in the default PDF viewer and displayed on your screen.

Other commands

To create new files for LilyPond, begin by selecting File > New

or File > Open to open and edit existing files you have saved previously.

You must save any new edits you make to your file before you Compile > Typeset and if the PDF file is not displayed check the window with the progress log for any errors.

If you are not using the default Preview PDF viewer that comes with the Mac Operating system and you have the PDF file generated from a previous compilation open, then any further compilations may fail to generate an update PDF until you close the original.

1.1.3 Windows

Step 1. Create your ‘.ly’ file

Double-click the LilyPond icon on your desktop and an example file will open.

From the menus that appear along the top of the example file, select File > Save as. Do not use the File > Save for the example file as this will not work until you have given it a valid LilyPond file name.

Choose a name for your file, for example ‘test.ly’.

Step 2. Compile

To turn your LilyPond file into a music score, you need to compile it. This can be done a number of ways – using drag and drop, with right-click, double-clicking or using the command line (a DOS box). We’ll look at the first three to start with.

1. Drag-and-drop the file directly onto the LilyPond icon on the desktop.

Not much will seem to happen, but after a short while, you should see two new files on your desktop – ‘test.log’ and ‘test.pdf’.

2. Right-click on the file and from the pop-up context menu and choose Generate PDF.

3. Or simply double-click the ‘test.ly’.

Step 3. View output

‘test.pdf’ contains the engraved ‘test.ly’ file. Double-click it and it should open in your PDF viewer:

Other commands

To create a new file, begin by selecting File > New from within any previously created file or File > Open to open and edit any files you have saved before. You can also edit a file by right-clicking it and selecting Edit source.

You must save any edits you make before you try to compile your file. If the PDF file is not created or the output is not what you expected, check the log file that will have been created during the compilation attempt for any errors.

This log file is overwritten each time you compile your LilyPond file.

If you are viewing your file in a PDF viewer, then you must close the PDF if you wish to try a new compilation as it may fail to create the new PDF while it is still being viewed.

1.1.4 命令行

Step 1. Create your ‘.ly’ file

Create a text file called ‘test.ly’ and enter:

\version "2.22.1"
{
  c' e' g' e'
}

Step 2. Compile (with command-line)

To process ‘test.ly’, type the following at the command prompt:

lilypond test.ly

You will see something resembling:

GNU LilyPond 2.22.1
Processing `test.ly'
Parsing...
Interpreting music...
Preprocessing graphical objects...
Solving 1 page-breaking chunks...[1: 1 pages]
Drawing systems...
Layout output to `test.ps'...
Converting to `./test.pdf'...
Success: compilation successfully completed

Step 3. View output

You may view or print the resulting ‘test.pdf’.

1.2 如何写输入文件

本节将会介绍介绍一些 LilyPond 的基本语法，帮助你开始写输入文件。

1.2.1 简单记谱法

LilyPond 会自动添加一些记谱元素。下面的例子中，我们只指定了四个音高，但是 LilyPond 已经为我们加上了谱号，拍子记号和节奏。

{
  c' e' g' e'
}

这些东西都是可以手动更改的，但是大多数情况下这些自动生成的东西十分有用。

音高

Music Glossary: pitch, interval, scale, middle C, octave, accidental.

LilyPond 用小写字母表示音高。 本节中所有例子中的音名都用荷兰命名系统（对应钢琴上的白键 c-b）. 然而 LilyPond 也支持很多不同的命名方法，比如英语，或者唱名 ‘Fixed-Do’ (do-re-mi-...). See Note names in other languages. 字母 c 到 b 表示 中央 C 下面的一个 ‘小八度’。加上 ' 或者 , 的后缀表示高八度或低八度。 下面是一段从 middle C 开始的音阶和琶音：

{ c' d' e' f' g' a' b' c'' g c' e' g' c'' e'' g'' c''' }

最简单的输入音符的方法是用 \relative （相对）模式. 这个模式中，系统会自动认为下一个音符总是处在与上一个音符最近的那个八度位置上。即它会位于上一个音符的上下三个谱表范围内。我们开始输入一段最基本的音乐，一段 音阶，其中每一个音符都是比上一个音符高一个谱表距离。

\relative {
  c' d e f
  g a b c
}

初始音符是 中央 C，记为 c'. 每一个后继音符都被放在与上一个音符最近的位置上 – 换句话说，第一个 c 是与中央 C 最近的 C。之后是与前面的 C 最近的 D。我们仍然可以使用 \relative 相对模式，写一段音高变化更大的旋律：

\relative {
  d' f a g
  c b f d
}

前面的例子中，第一个音符 – d' 有一个单引号 ' 标记 – 表示处在中央 C 到上面的 B 之间的这个八度中的 D。

通过从第一个音符中添加或移除单引号 ' 或逗号 , 我们可以更改起始的八度。

\relative {
  e'' c a c
}

相对模式一开始可能有点乱，但确实是最方便的输入旋律的方法。接下来我们看一下实际应用中相对模式到底如何计算的。从一个高音谱中中间线上的 B 开始，向上可以达到在其上三个谱表距离之内的 C, D, E，向下可以达到在其下三个谱表距离之内的 A, G, F。所以如果 B 后面跟的是 C, D, E，它们就会被默认是在 B 之上的，如果后面跟的是 A, G, F，它们就会被默认是在 B 之下的。

\relative {
  b' c % c is 1 staff space up, so is the c above
  b d  % d is 2 up or 5 down, so is the d above
  b e  % e is 3 up or 4 down, so is the e above
  b a  % a is 6 up or 1 down, so is the a below
  b g  % g is 5 up or 2 down, so is the g below
  b f  % f is 4 up or 3 down, so is the f below
}

不管这些音符是被升了还是降了，结果都是一样的，只取决于其本身在谱子上的位置。变音记号 在计算相对位置时会 完全被忽略掉。 谱表上处于任何位置的谱线之间的距离计算总是等价的。

使音程大于三个谱线距离，我们可以通过加入一个 ' 来对这个音符进一步升高一个 八度；可以通过加入一个逗号 , 来对这个音符进一步降低一个 八度。

\relative {
  a' a, c' f,
  g g'' a,, f'
}

要改变两个或（或更多!）八度，可以用多个 '' 或 ,, – 但要注意这里是两个单引号 '' 而不是一个双引号 " !

时值 (节奏)

音乐术语： beam, duration, whole note, half note, quarter note, dotted note.

一个音符的 时值 由音符后面的数字确定：1 为全音符，2 为半音符，4 为四分音符，以此类推。连音会自动生成.

如果你不指定时值，那么该音符的时值就会和上一个音符一样。第一个音符如果不加声明，则默认为四分音符。

\relative {
  a'1
  a2 a4 a8 a
  a16 a a a a32 a a a a64 a a a a a a a a2
}

要写附点音符，只需要在时值数字后面加一个 . 就可以了。浮点音符的点前面必须有数字。

\relative {
  a'4 a a4. a8
  a8. a16 a a8. a8 a4.
}

休止符

音乐术语： rest.

休止符用 r  表示：

\relative {
  a'4 r r2
  r8 a r4 r4. r8
}

拍子记号

音乐术语： time signature.

拍子记号用 \time 命令设置：

\relative {
  \time 3/4
  a'4 a a
  \time 6/8
  a4. a
  \time 4/4
  a4 a a a
}

速度记号

音乐术语： tempo indication, metronome.

速度记号和节拍器记号用 \tempo 命令设置：

\relative {
  \time 3/4
  \tempo "Andante"
  a'4 a a
  \time 6/8
  \tempo 4. = 96
  a4. a
  \time 4/4
  \tempo  "Presto" 4 = 120
  a4 a a a
}

谱号（音部记号）

音乐术语： clef.

谱号用 \clef 命令设置：

\relative {
  \clef "treble"
  c'1
  \clef "alto"
  c1
  \clef "tenor"
  c1
  \clef "bass"
  c1
}

所有的都放在一起

下面这个例子把我们现在学过的元素都用上了：

\relative {
  \clef "bass"
  \time 3/4
  \tempo "Andante" 4 = 120
  c,2 e8 c'
  g'2.
  f4 e d
  c4 c, r
}

参见

记谱法参考： Writing pitches, Writing rhythms, Writing rests, Time signature, Clef.

1.2.2 处理输入文件

LilyPond 输入文件和很多编程语言的源文件非常类似。他们都包含版本声明，都是区分大小写的，都会自动忽略掉空格。表达式用大括号 { } 组织，注释用 % 或 %{ … %}  表示。

如果你不理解前面所说的，也没有关系！下面就会一一解释他们的意思：

• 版本声明: 每一个 LilyPond 文件都会带有一个版本声明。版本声明是一行

  \version "2.23.3"
  

  依惯例，版本声明会放在 LilyPond 文件的最开头。

  版本声明非常重要，原因有二。一是它能够使得 LilyPond 语法更新自动应用在输入文件上。二是它指明了编译这份文件所需的 LilyPond 版本。

  如果输入文件中忘记标版本声明了，LilyPond 会在编译文件时给出警告。

• 大小写敏感: 小写 (e.g. a, b, s, t) 和大写 (e.g. A, B, S, T) 的效果是不一样的。音符都是用小写字母表示的：‘{ c d e }’ 是有效的输入； ‘{ C D E }’ 会报错。
• 空格不敏感: 多少个空格（或制表符或换行）都不重要（不起作用）。下面这三个都是一样的效果：‘{ c4 d e }’， ‘{ c4       d e }’ 和：

  { c4                       d
                     e   }
  

  当然，最后一个写法很不易读。所以最好在一个代码块中加入两个空格（或一个制表符）的缩进：

  {
    c4 d e
  }
  

  然而，空格是需要用来分隔不同语法元素的。换句话说，空格总可以多加，但不一定能省略。因为缺失必要的空格分隔会导致出现奇怪的错误，所以强烈建议在每一个语法元素前后都加上空格，和前后语法元素隔开；比如每个大括号前后都加上空格。

• 表达式: 每条 LilyPond 输入都需要用 { 大括号 } 括起来。这些大括号告诉 LilyPond 括号里的输入是一个单独的音乐表达式，就像数学中的小括号 () 一样。 这些括号两侧都需要加入空格以避免歧义，除非是在行首或行末。

  一个 LilyPond 指令后面跟的大括号内的简单表达式（如 ‘relative { … }’）也会被视为单一音乐表达式。

• Comments: 注释是为了让人们读懂音乐输入而写的标记；注释会在语法分析中被忽略掉，所以不会对输出结果产生影响。注释有两种类型：百分号 % 是单行注释；该行在 % 后的内容都会被编译器忽略。依惯例，单行注释都加在要说明的代码之上。

  a4 a a a
  % this comment refers to the Bs
  b2 b
  

  注释块标记表明一大段音乐输入都是注释。所有在 %{ 和 %} 之间的内容都会被忽略。然而，注释块不能‘嵌套’。这意味着你不能把注释块放在另一个注释块内。如果你这样尝试的话，第一个 %} 会终止 这两个注释块。下面是展示可能用到注释块情形：

  % notes for twinkle twinkle follow
    c4 c g' g a a g2
  
  %{
    This line, and the notes below are ignored,
    since they are in a block comment.
  
    f4 f e e d d c2
  %}
  

1.3 处理报错

有时候 LilyPond 没有输出你想要的结果。这一节会为你通过一些链接帮助你解决这些你可能遇到的问题。

1.3.1 一般解决问题的方法

解决 LilyPond 的问题对于熟悉使用图形化交互界面的人来说可能很具有挑战性，因为无效的输入文件可能会被创建。当这种情况发生时，一个符合逻辑的方法就是最好的确定并解决问题的方法。 Troubleshooting 中提供了一些指导，可以帮你学会这些方法。

1.3.2 常见的错误

有一些常见错误，仅靠显示的简单报错信息也很难解决。这些在 Common errors 中有具体说明。

1.4 如何阅读教程

这一节展示了如何高效阅读文档，并介绍了一些在线版本中有用的交互性特征。

1.4.1 忽略掉的内容

LilyPond 必须写在 { } 或 ‘relative { … }’ 中，正如 @ref{Working on input files} 中所说的。教程的后面部分，会涉及一些简短的例子，会忽略掉这种符号。如果你想复制这些例子的话，你可以直接复制这些例子，但需要把它们粘贴在 { 和 } 中。

{
  …example goes here…
}

当然，要记住每一个 LilyPond 文件都需要有 \version 声明。由于教程中的例子都是片段而非文件， \version 声明也忽略掉了。但你需要在实际使用中加上这个版本声明。

1.4.2 可以点开的例子

很多人学编程都是通过不断地尝试探索。学 LilyPond 也是一样的。如果你点击 HTML 版本教程的图片，你可以看到生成图片中例子所对应的原始的 LilyPond 输入。试试下面这个图像吧：

复制粘贴 "ly snippet" 部分的内容，得到的是一个用于实验的模板。如果想得到完全一样的输出结果（包括行距等等），就要复制粘贴 "Start cut-&-pastable section" 之后的全部内容。

1.4.3 手册概览

LilyPond 有很多文档。新用户可能有时候不知道应该阅读哪一部分，并且有时候会跳过重要的部分。

• 在做 任何事 之前：请阅读 Learning manual’s 教程 和 Common notation。如果你遇到了你不认识的音乐术语，请看 Glossary.
• 在写一段完整音乐之前：阅读学习教程的 Fundamental concepts。之后，你可能会想去看 Notation reference 部分的相关章节。
• 在改变默认输出之前：阅读学习教程 Tweaking output 部分。
• 在做大项目之前: 阅读用户手文档的 Suggestions for writing files 部分。

2 Common notation

This chapter explains how to create beautiful printed music containing common musical notation, following the material in @ref{Tutorial}.

2.1 Single staff notation

This section introduces common notation that is used for one voice on one staff.

2.1.1 Bar lines and bar checks

Bar lines

Single bar lines are automatically placed in the music so there is no need to add them manually. Other types of bar lines are added using \bar, for example \bar "||" for a double bar line, or \bar "|." for an ending bar line. For a full list of bar lines see the Bar lines.

\relative { g'1 e1 \bar "||" c2. c'4 \bar "|." }

Bar checks

Though not strictly necessary, bar checks should be used in the input code to show where bar lines are expected to fall. They are entered using the bar symbol, |. With bar checks, the program can verify that you’ve entered durations that make each measure add up to the correct length. Bar checks also make your input code easier to read, since they help to keep things organized.

\relative {
  g'1 | e1 | c2. c' | g4 c g e | c4 r r2 |
}

If you compile the code in the example above, you should see a warning in the console output:

warning: barcheck failed at: 1/2
 g'1 | e1 | c2. c'
                   | g4 c g e | c4 r r2 |

Although the missing duration is clear in the musical output in this simple example, the warning in the console output is far more effective in drawing attention to the missing 4 in bar 3.

参见

Notation Reference: Bar and bar number checks.

2.1.2 Pitches and key signatures

Pitch alterations

Music Glossary: sharp, flat, double sharp, double flat, accidental.

Note-names in LilyPond identify pitches. For example, c always means C-natural, regardless of the key signature.

In many languages, a note name consists of a base name refering to the diatonic steps of the C major / a minor scale, e.g. d, and a suffix, which indicates alteration of this base pitch. The default input language for note names is nederlands (Dutch). A sharp pitch is made by adding is to the name, and a flat pitch by adding es. As you might expect, a double sharp or double flat is made by adding isis or eses. This syntax is derived from note naming conventions in Nordic and Germanic languages, like German and Dutch. To use other naming schemes for note names, see Note names in other languages.

\relative { cis''4 ees fisis, aeses }

Key signatures

Music Glossary: key signature, major, minor.

The key signature is set with the command \key followed by a pitch and \major or \minor.

\relative {
  \key d \major
  d'4 fis a c |
  \bar "||" \key c \minor
  c,4 ees g b |
}

Warning: key signatures and pitches

Music Glossary: accidental, key signature, pitch, flat, natural, sharp, transposition, Pitch names.

LilyPond makes a distinction between musical content and its printed representation. Input such as d4 e fis2 defines the pitches and durations of notes, which is musical content. The key signature is part of the printed representation. The key signature also sets rules for the printed representations of notes. LilyPond compares each input pitch to the key signature to determine whether to print an accidental.

The command \key sets the key signature, which affects the printed representation, but does not change the pitch assigned to a note such as c in the input.

In this example:

\relative {
  \key d \major
  cis''4 d e fis
}

No note has a printed accidental, but you must still add is and type cis and fis in the input file.

The code b does not mean “print a black dot just on the middle line of the staff.” Rather, it means “there is a note with pitch B-natural.” In the key of A-flat major, it does get an accidental:

\relative {
  \key aes \major
  aes'4 c b c
}

Whenever you enter a pitch that is a black key on the piano, you must add -is or -es to the note name.

Adding all alterations explicitly might require a little more effort when typing, but the advantage is that transposing is easier, and accidentals can be printed according to different conventions. For some examples of how accidentals can be printed according to different rules, see Automatic accidentals.

参见

Notation Reference: Note names in other languages, Accidentals, Automatic accidentals, Key signature.

2.1.3 Ties and slurs

Ties

Music Glossary: tie.

A tie is created by appending a tilde ~ to the first of the two notes being tied.

\relative { g'4~ g c2~ | c4~ c8 a~ a2 | }

When the pitch does not change, as is always the case with tied notes, subsequent pitches may be omitted, specifying just the bare duration:

\relative { g'4~ 4 c2~ | 4~ 8 a~ 2 | }

This shorthand may be useful in other places where the rhythm changes with an unchanging pitch, but remember that a bare pitch followed by a space and a bare duration will be interpreted as a single note. In other words, c4 a 8 8 would be interpreted as c4 a8 a8, not as c4 a4 a8 a8. Write instead c4 a4 8 8 .

Slurs

Music Glossary: slur.

A slur is a curve drawn across many notes. The starting note and ending note are marked with ( and ) respectively. Note that the ( comes after the first note of the slur.

\relative { d''4( c16) cis( d e c cis d) e( d4) }

Phrasing slurs

Music Glossary: slur, phrasing.

Slurs to indicate longer phrasing can be entered with \( and \). You can have both slurs and phrasing slurs at the same time.

\relative { g'4\( g8( a) b( c) b4\) }

Warnings: slurs vs. ties

Music Glossary: articulation, slur, tie.

A slur looks like a tie, but it has a different meaning. A tie simply makes the first note longer, and can only be used on pairs of notes with the same pitch. Slurs indicate the articulation of notes, and can be used on larger groups of notes. Slurs and ties can be nested.

\relative { c''4(~ c8 d~ 4 e) }

参见

Notation Reference: Ties, Slurs, Phrasing slurs.

2.1.4 Articulations and dynamics

Articulations and dynamics are indicated by adding special codes after the notes to which they apply,

Articulations

Music Glossary: articulation.

Common articulations can be added to a note using a dash - and a single character:

\relative {
  c''4-^ c-+ c-- c-!
  c4-> c-. c2-_
}

Fingerings

Music Glossary: fingering.

Similarly, fingering indications can be added to a note using a dash (-) and the digit to be printed:

\relative { c''4-3 e-5 b-2 a-1 }

Articulations and fingerings are usually placed automatically, but you can specify a direction by replacing the dash (-) with ^ (up) or _ (down). You can also use multiple articulations on the same note. However, in most cases it is best to let LilyPond determine the articulation directions.

\relative { c''4_-^1 d^. f^4_2-> e^-_+ }

Dynamics

Music Glossary: dynamics, crescendo, decrescendo.

Dynamic signs are made by adding the markings (with a backslash) to the note:

\relative { c''4\ff c\mf c\p c\pp }

Crescendi and decrescendi are started with the commands \< and \>. The next dynamics sign, for example \f, will end the (de)crescendo, or the command \! can be used:

\relative { c''4\< c\ff\> c c\! }

参见

Notation Reference: Articulations and ornamentations, Fingering instructions, Dynamics.

2.1.5 Adding text

Text may be added to your scores:

c''2^"espr" a'_"legato"

Extra formatting may be added with the \markup command:

c''2^\markup { \bold espr }
a'2_\markup {
  \dynamic f \italic \small { 2nd } \hspace #0.1 \dynamic p
}

参见

Notation Reference: Writing text.

2.1.6 Automatic and manual beams

Music Glossary: beam.

All beams are drawn automatically:

\relative { a'8 ais d ees r d c16 b a8 }

If you do not like the automatic beams, they may be overridden manually. To correct just an occasional beam mark the first note to be beamed with [ and the last one with ]. Note that [ comes after the first beamed note.

\relative { a'8[ ais] d[ ees r d] c16 b a8 }

If you want to turn off automatic beaming entirely or for an extended section of music, use the command \autoBeamOff to turn off automatic beaming and \autoBeamOn to turn it on again.

\relative {
  \autoBeamOff
  a'8 c b4 d8. c16 b4 |
  \autoBeamOn
  a8 c b4 d8. c16 b4 |
}

参见

Notation Reference: Automatic beams, Manual beams.

2.1.7 Advanced rhythmic commands

Partial measure

Music Glossary: anacrusis.

A pickup (or anacrusis) is entered with the keyword \partial. It is followed by a duration: \partial 4 is a quarter note pickup and \partial 8 an eighth note.

\relative {
  \partial 8 f''8 |
  c2 d |
}

Tuplets

Music Glossary: note value, triplet.

Tuplets are made with the \tuplet keyword. It takes two arguments: a fraction and a piece of music. The fraction is the number of tuplet notes over the number of notes normally filling the same duration. For triplets, there are three notes instead of two, so triplets have 3/2 as their fraction.

\relative {
  \tuplet 3/2 { f''8 g a }
  \tuplet 3/2 { c8 r c }
  \tuplet 3/2 { f,8 g16[ a g a] }
  \tuplet 3/2 { d4 a8 }
}

Grace notes

Music Glossary: grace notes, acciaccatura, appoggiatura.

Grace notes are created with the \grace command, although they can also be created by prefixing a music expression with the keyword \appoggiatura or \acciaccatura:

\relative {
  c''2 \grace { a32 b } c2 |
  c2 \appoggiatura b16 c2 |
  c2 \acciaccatura b16 c2 |
}

参见

Notation Reference: Grace notes, Tuplets, Upbeats.

2.2 Multiple notes at once

This section introduces having more than one note at the same time: multiple instruments, multiple staves for a single instrument (i.e. piano), and chords.

Polyphony in music refers to having more than one voice occurring in a piece of music. Polyphony in LilyPond refers to having more than one voice on the same staff.

2.2.1 Music expressions explained

In LilyPond input files, music is represented by music expressions. A single note is a music expression:

a'4

Enclosing a note in braces creates a compound music expression. Here we have created a compound music expression with two notes:

\relative { a'4 g4 }

Putting a group of music expressions (e.g. notes) in braces means that they are in sequence (i.e. each one follows the previous one). The result is another music expression:

\relative { { a'4 g } f4 g }

Analogy: mathematical expressions

This mechanism is similar to mathematical formulas: a big formula is created by composing small formulas. Such formulas are called expressions, and they can contain other expressions, so you can make arbitrarily complex and large expressions. For example,

1

1 + 2

(1 + 2) * 3

((1 + 2) * 3) / (4 * 5)

This is a sequence of expressions, where each expression is contained in the next (larger) one. The simplest expressions are numbers, and larger ones are made by combining expressions with operators (like +, * and /) and parentheses. Like mathematical expressions, music expressions can be nested arbitrarily deep, which is necessary for complex music like polyphonic scores.

Simultaneous music expressions: multiple staves

Music Glossary: polyphony.

This technique is useful for polyphonic music. To enter music with more voices or more staves, we combine expressions in parallel. To indicate that two voices should play at the same time, simply enter a simultaneous combination of music expressions. A ‘simultaneous’ music expression is formed by enclosing expressions inside << and >>. In the following example, three sequences (all containing two separate notes) are combined simultaneously:

<<
  \relative { a'2 g }
  \relative { f'2 e }
  \relative { d'2 b }
>>

Note that we have indented each level of the input with a different amount of space. LilyPond does not care how much (or little) space there is at the beginning of a line, but indenting LilyPond code like this makes it much easier for humans to read.

Simultaneous music expressions: single staff

To determine the number of staves in a piece, LilyPond looks at the beginning of the first expression. If there is a single note, there is one staff; if there is a simultaneous expression, there is more than one staff. The following example shows a complex expression, but as it begins with a single note it will be set out on a single staff.

\relative {
  c''2 <<c e>> |
  << { e2 f } { c2 <<b d>> } >> |
}

2.2.2 Multiple staves

LilyPond input files are constructed out of music expressions, as we saw in Music expressions explained. If the score begins with simultaneous music expressions, LilyPond creates multiples staves. However, it is easier to see what happens if we create each staff explicitly.

To print more than one staff, each piece of music that makes up a staff is marked by adding \new Staff before it. These Staff elements are then combined in parallel with << and >>:

<<
  \new Staff { \clef "treble" c''4 }
  \new Staff { \clef "bass" c4 }
>>

The command \new introduces a ‘notation context.’ A notation context is an environment in which musical events (like notes or \clef commands) are interpreted. For simple pieces, such notation contexts are created automatically. For more complex pieces, it is best to mark contexts explicitly.

There are several types of contexts. Score, Staff, and Voice handle melodic notation, while Lyrics sets lyric texts and ChordNames prints chord names.

In terms of syntax, prepending \new to a music expression creates a bigger music expression. In this way it resembles the minus sign in mathematics. The formula (4+5) is an expression, so -(4+5) is a bigger expression.

Time signatures entered in one staff affect all other staves by default. On the other hand, the key signature of one staff does not affect other staves. This different default behavior is because scores with transposing instruments are more common than polyrhythmic scores.

<<
  \new Staff { \clef "treble" \key d \major \time 3/4 c''4 }
  \new Staff { \clef "bass" c4 }
>>

2.2.3 Staff groups

Music Glossary: brace, staff, system.

Piano music is typeset in two staves connected by a brace. Printing such a staff is similar to the polyphonic example in Multiple staves. However, now this entire expression is inserted inside a PianoStaff:

\new PianoStaff <<
  \new Staff …
  \new Staff …
>>

Here is a small example:

\new PianoStaff <<
  \new Staff \relative { \time 2/4 c''4 e | g g, | }
  \new Staff \relative { \clef "bass" c4 c' | e c | }
>>

Other staff groupings are introduced with \new GrandStaff, suitable for orchestral scores, and \new ChoirStaff, suitable for vocal scores. These staff groups each form another type of context, one that generates the brace at the left end of every system and also controls the extent of bar lines.

参见

Notation Reference: Keyboard and other multi-staff instruments, Displaying staves.

2.2.4 Combining notes into chords

Music Glossary: chord

We saw earlier how notes can be combined into chords by indicating they are simultaneous by enclosing them in double angle brackets. However, the normal way of indicating a chord is to surround the pitches with single angle brackets. Note that all the notes in a chord must have the same duration, and that the duration is placed after the closing bracket.

\relative { r4 <c'' e g> <c f a>2 }

Think of chords as almost equivalent to single notes: almost everything you can attach to a single note can be attached to a chord, and everything must go outside the angle brackets. For example, you can combine markings like beams and ties with chords. They must be placed outside the angle brackets.

\relative {
  r4 <c'' e g>~ <c f a>2 |
  <c e g>8[ <c f a> <c e g> <c f a>]
    <c e g>8\>[ <c f a> <c f a> <c e g>]\! |
  r4 <c e g>8.\p <c f a>16( <c e g>4-. <c f a>) |
}

参见

Notation Reference: Chorded notes.

2.2.5 Single staff polyphony

Polyphonic music in lilypond, while not difficult, uses concepts that we haven’t discussed yet, so we’re not going to introduce them here. Instead, the following sections introduce these concepts and explain them thoroughly.

参见

Learning Manual: Voices contain music.

Notation Reference: Simultaneous notes.

2.3 Songs

This section introduces vocal music and simple song sheets.

2.3.1 Setting simple songs

Music Glossary: lyrics.

Here is the start of the melody to a nursery rhyme, Girls and boys come out to play:

\relative {
  \key g \major
  \time 6/8
  d''4 b8 c4 a8 | d4 b8 g4
}

The lyrics can be set to these notes, combining both with the \addlyrics keyword. Lyrics are entered by separating each syllable with a space.

<<
  \relative {
    \key g \major
    \time 6/8
    d''4 b8 c4 a8 | d4 b8 g4
  }
  \addlyrics {
    Girls and boys come out to play,
  }
>>

Note the double angle brackets <<…>> around the whole piece to show that the music and lyrics are to occur at the same time.

2.3.2 Aligning lyrics to a melody

Music Glossary: melisma, extender line.

The next line in the nursery rhyme is The moon doth shine as bright as day. Let’s extend it:

<<
  \relative {
    \key g \major
    \time 6/8
    d''4 b8 c4 a8 | d4 b8 g4 g8 |
    a4 b8 c b a | d4 b8 g4. |
  }
  \addlyrics {
    Girls and boys come out to play,
    The moon doth shine as bright as day;
  }
>>

Looking at the music, we see that the extra lyrics do not align properly with the notes. The word shine should be sung on two notes, not one. This is called a melisma, a single syllable sung to more than one note. There are several ways to spread a syllable over multiple notes, the simplest being to add a slur across them, for details, see Ties and slurs:

<<
  \relative {
    \key g \major
    \time 6/8
    d''4 b8 c4 a8 | d4 b8 g4 g8 |
    a4 b8 c( b) a | d4 b8 g4. |
  }
  \addlyrics {
    Girls and boys come out to play,
    The moon doth shine as bright as day;
  }
>>

The words now line up correctly with the notes, but the automatic beaming for the notes above shine as does not look right. We can correct this by inserting manual beaming commands to override the automatic beaming here, for details, see Automatic and manual beams.

<<
  \relative {
    \key g \major
    \time 6/8
    d''4 b8 c4 a8 | d4 b8 g4 g8 |
    a4 b8 c([ b]) a | d4 b8 g4. |
  }
  \addlyrics {
    Girls and boys come out to play,
    The moon doth shine as bright as day;
  }
>>

As an alternative to using slurs, the melismata may be indicated in just the lyrics by using an underscore _ for each note that should be included in the melisma:

<<
  \relative {
    \key g \major
    \time 6/8
    d''4 b8 c4 a8 | d4 b8 g4 g8 |
    a4 b8 c[ b] a | d4 b8 g4. |
  }
  \addlyrics {
    Girls and boys come out to play,
    The moon doth shine _ as bright as day;
  }
>>

If a syllable extends over several notes or a single very long note an extender line is usually drawn from the syllable extending under all the notes for that syllable. It is entered as two underscores __. Here is an example from the first three bars of Dido’s Lament, from Purcell’s Dido and Æneas:

<<
  \relative {
    \key g \minor
    \time 3/2
    g'2 a bes | bes2( a) b2 |
    c4.( bes8 a4. g8 fis4.) g8 | fis1
  }
  \addlyrics {
    When I am laid,
    am laid __ in earth,
  }
>>

None of the examples so far have involved words containing more than one syllable. Such words are usually split one syllable to a note, with hyphens between syllables. Such hyphens are entered as two dashes, resulting in a centered hyphen between the syllables. Here is an example showing this and everything we have learned so far about aligning lyrics to notes.

<<
  \relative {
    \key g \major
    \time 3/4
    \partial 4
    d'4 | g4 g a8( b) | g4 g b8( c) |
    d4 d e | c2
  }
  \addlyrics {
    A -- way in a __ man -- ger,
    no __ crib for a bed,
  }
>>

Some lyrics, especially those in Italian, require the opposite: setting more than one syllable to a single note. This is achieved by linking the syllables together with a single underscore _ (with no spaces), or enclosing them in quotes. Here’s an example from Rossini’s Figaro, where al has to be sung on the same note as the go of Largo in Figaro’s aria Largo al factotum:

<<
  \relative {
    \clef "bass"
    \key c \major
    \time 6/8
    c'4.~ 8 d b | c8([ d]) b c d b | c8
  }
  \addlyrics {
    Lar -- go_al fac -- to -- tum del -- la cit -- tà
  }
>>

参见

Notation Reference: Vocal music.

2.3.3 Lyrics to multiple staves

The simple approach using \addlyrics can be used for placing lyrics under more than one staff. Here is an example from Handel’s Judas Maccabæus:

<<
  \relative {
    \key f \major
    \time 6/8
    \partial 8
    c''8 | c8([ bes]) a a([ g]) f | f'4. b, | c4.~ 4
  }
  \addlyrics {
    Let flee -- cy flocks the hills a -- dorn, __
  }
  \relative {
    \key f \major
    \time 6/8
    \partial 8
    r8 | r4. r4 c'8 | a'8([ g]) f f([ e]) d | e8([ d]) c bes'4
  }
  \addlyrics {
    Let flee -- cy flocks the hills a -- dorn,
  }
>>

Scores any more complex than this simple example are better produced by separating out the score structure from the notes and lyrics with variables. These are discussed in Organizing pieces with variables.

参见

Notation Reference: Vocal music.

2.4 Final touches

This is the final section of the tutorial; it demonstrates how to add the final touches to simple pieces, and provides an introduction to the rest of the manual.

2.4.1 Organizing pieces with variables

When all of the elements discussed earlier are combined to produce larger files, the music expressions get a lot bigger. In polyphonic music with many staves, the input files can become very confusing. We can reduce this confusion by using variables.

With variables (also known as identifiers or macros), we can break up complex music expressions. A variable is assigned as follows:

namedMusic = { … }

The contents of the music expression namedMusic can be used later by placing a backslash in front of the name (\namedMusic, just like a normal LilyPond command).

violin = \new Staff {
  \relative {
    a'4 b c b
  }
}

cello = \new Staff {
  \relative {
    \clef "bass"
    e2 d
  }
}

{
  <<
    \violin
    \cello
  >>
}

By convention, variable names consist of alphabetic characters only. For detailed information, see File structure.

Variables must be defined before the main music expression, but may be used as many times as required anywhere after they have been defined. They may even be used in a later definition of another variable, giving a way of shortening the input if a section of music is repeated many times.

tripletA = \relative { \tuplet 3/2 { c'8 e g } }
barA = { \tripletA \tripletA \tripletA \tripletA }

{ \barA \barA }

Variables may be used for many other types of objects in the input. For example,

myWidth = 60      % a number to pass to a \paper variable (the unit is millimeter)
myName = "Wendy"  % a string to pass to a markup
aFivePaper = \paper { #(set-paper-size "a5") }

Depending on its contents, the variable can be used in different places. The following example uses the above variables:

\paper {
  \aFivePaper
  line-width = \myWidth
}

{
  c4^\myName
}

2.4.2 Adding titles

The title, composer, opus number, and similar information are entered in the \header block. This exists outside of the main music expression; the \header block is usually placed underneath the version number.

\version "2.23.3"

\header {
  title = "Symphony"
  composer = "Me"
  opus = "Op. 9"
}

{
  … music …
}

When the file is processed, the title and composer are printed above the music. More information on titling can be found in Creating titles headers and footers.

2.4.3 Absolute note names

So far we have used \relative to define pitches. This is usually the fastest way to enter most music. Without \relative, pitches are interpreted in absolute mode.

In this mode, LilyPond treats all pitches as absolute values. A c' will always mean middle C, a b will always mean the note one step below middle C, and a g, will always mean the note on the bottom staff of the bass clef.

{
  \clef "bass"
  c'4 b g, g, |
  g,4 f, f c' |
}

Writing a melody in the treble clef involves a lot of quote ' marks. Consider this fragment from Mozart:

{
  \key a \major
  \time 6/8
  cis''8. d''16 cis''8 e''4 e''8 |
  b'8. cis''16 b'8 d''4 d''8 |
}

Common octave marks can be indicated just once, using the command \fixed followed by a reference pitch:

\fixed c'' {
  \key a \major
  \time 6/8
  cis8. d16 cis8 e4 e8 |
  b,8. cis16 b,8 d4 d8 |
}

With \relative, the previous example needs no octave marks because this melody moves in steps no larger than three staff positions:

\relative {
  \key a \major
  \time 6/8
  cis''8. d16 cis8 e4 e8 |
  b8. cis16 b8 d4 d8 |
}

If you make a mistake with an octave mark (' or ,) while working in \relative mode, it is very obvious – many notes will be in the wrong octave. When working in absolute mode, a single mistake will not be as visible, and will not be as easy to find.

However, absolute mode is useful for music which has large intervals, and is extremely useful for computer-generated LilyPond files. When cutting and pasting melody fragments, absolute mode preserves the original octave.

Sometimes music is arranged in more complex ways. If you are using \relative inside of \relative, the outer and inner relative sections are independent:

\relative { c'4 \relative { f'' g } c }

To use absolute mode inside of \relative, put the absolute music inside \fixed c { … } and the absolute pitches will not affect the octaves of the relative music:

\relative {
  c'4 \fixed c { f'' g'' } c |
  c4 \fixed c'' { f g } c
}

2.4.4 After the tutorial

After finishing the tutorial, you should probably try writing a piece or two. Start by adding notes to one of the Templates. If you need any notation that was not covered in the tutorial, look at the Notation Reference, starting with Musical notation. If you want to write for an instrument ensemble that is not covered in the templates, take a look at Extending the templates.

Once you have written a few short pieces, read the rest of the Learning Manual (chapters 3-5). There’s nothing wrong with reading it now, of course! However, the rest of the Learning Manual assumes that you are familiar with LilyPond input. You may wish to skim these chapters right now, and come back to them after you have more experience.

In this tutorial and in the rest of the Learning Manual, there is a paragraph See also at the end of each section, which contains cross-references to other sections: you should not follow these cross-references at first reading; when you have read all of the Learning Manual, you may want to read some sections again and follow cross-references for further reading.

If you have not done so already, please read @ref{Overview of manuals}. There is a lot of information about LilyPond, so newcomers often do not know where they should look for help. If you spend five minutes reading that section carefully, you might save yourself hours of frustration looking in the wrong places!

3 Fundamental concepts

You’ve seen in the Tutorial how to produce beautifully printed music from a simple text file. This section introduces the concepts and techniques required to produce equally beautiful but more complex scores.

3.1 How LilyPond input files work

The LilyPond input format is quite free-form, giving experienced users a lot of flexibility to structure their files however they wish. But this flexibility can make things confusing for new users. This section will explain some of this structure, but may gloss over some details in favor of simplicity. For a complete description of the input format, see File structure.

3.1.1 Introduction to the LilyPond file structure

A basic example of a LilyPond input file is

\version "2.23.3"

\header { }

\score {
   … compound music expression …   % all the music goes here!
  \layout { }
  \midi { }
}

There are many variations of this basic pattern, but this example serves as a useful starting place.

Up to this point none of the examples you have seen have used a \score{} command. This is because LilyPond automatically adds the extra commands which are needed when you give it simple input. LilyPond treats input like this:

\relative {
  c''4 a b c
}

as shorthand for this:

\book {
  \score {
    \new Staff {
      \new Voice {
        \relative {
          c''4 a b c
        }
      }
    }
    \layout { }
  }
}

In other words, if the input contains a single music expression, LilyPond will interpret the file as though the music expression was wrapped up inside the commands shown above.

A word of warning! Many of the examples in the LilyPond documentation will omit the \new Staff and \new Voice commands, leaving them to be created implicitly. For simple examples this works well, but for more complex examples, especially when additional commands are used, the implicit creation of contexts can give surprising results, maybe creating extra unwanted staves. The way to create contexts explicitly is explained in Contexts and engravers.

For now, though, let us return to the first example and examine the \score command, leaving the others to default.

A \score block must always contain exactly one music expression. Remember that a music expression could be anything from a single note to a huge compound expression like

{
  \new StaffGroup <<
     … insert the whole score of a Wagner opera in here … 
  >>
}

Since everything is inside { … }, it counts as one music expression.

As we saw previously, the \score block can contain other things, such as

\score {
  { c'4 a b c' }
  \header { }
  \layout { }
  \midi { }
}

Note that these three commands – \header, \layout and \midi – are special: unlike many other commands which begin with a backward slash (\) they are not music expressions and are not part of any music expression. So they may be placed inside a \score block or outside it. In fact, these commands are commonly placed outside the \score block – for example, \header is often placed above the \score command, as the example at the beginning of this section shows.

Two more commands you have not previously seen are \layout { } and \midi {}. If these appear as shown they will cause LilyPond to produce a printed output and a MIDI output respectively. They are described fully in the Notation Reference – Score layout, and Creating MIDI output.

You may code multiple \score blocks. Each will be treated as a separate score, but they will be all combined into a single output file. A \book command is not necessary – one will be implicitly created. However, if you would like separate output files from one ‘.ly’ file then the \book command should be used to separate the different sections: each \book block will produce a separate output file.

In summary:

Every \book block creates a separate output file (e.g., a PDF file). If you haven’t explicitly added one, LilyPond wraps your entire input code in a \book block implicitly.

Every \score block is a separate chunk of music within a \book block.

Every \layout block affects the \score or \book block in which it appears – i.e., a \layout block inside a \score block affects only that \score block, but a \layout block outside of a \score block (and thus in a \book block, either explicitly or implicitly) will affect every \score in that \book.

For details see Multiple scores in a book.

Another great shorthand is the ability to define variables, as shown in Organizing pieces with variables. All the templates use this:

melody = \relative {
  c'4 a b c
}

\score {
  \melody
}

When LilyPond looks at this file, it takes the value of melody (everything after the equals sign) and inserts it whenever it sees \melody. There’s nothing special about the name – it could be melody, global, keyTime, pianorighthand, or something else. Remember that you can use almost any name you like as long as it contains just alphabetic characters and is distinct from LilyPond command names. For more details, see Saving typing with variables and functions. The exact limitations on variable names are detailed in File structure.

参见

For a complete definition of the input format, see File structure.

3.1.2 Score is a (single) compound musical expression

We saw the general organization of LilyPond input files in the previous section, Introduction to the LilyPond file structure. But we seemed to skip over the most important part: how do we figure out what to write after \score?

We didn’t skip over it at all. The big mystery is simply that there is no mystery. This line explains it all:

A \score block must contain exactly one music expression.

To understand what is meant by a music expression, you may find it useful to review the tutorial, Music expressions explained. In that section, we saw how to build big music expressions from small pieces – we started from notes, then chords, etc. Now we’re going to start from a big music expression and work our way down. For simplicity, we’ll use just a singer and piano in our example. We don’t need a StaffGroup for this ensemble, which simply groups a number of staves together with a bracket at the left, but we do need staves for a singer and a piano, though.

\score {
  <<
    \new Staff = "singer" <<
    >>
    \new PianoStaff = "piano" <<
    >>
  >>
  \layout { }
}

Here we have given names to the staves – “singer” and “piano”. This is not essential here, but it is a useful habit to cultivate so that you can see at a glance what each stave is for.

Remember that we use << … >> instead of { … } to show simultaneous music. This causes the vocal part and piano part to appear one above the other in the score. The << … >> construct would not be necessary for the Singer staff in the example above if it were going to contain only one sequential music expression, but << … >> rather than braces is necessary if the music in the Staff is to contain two or more simultaneous expressions, e.g. two simultaneous Voices, or a Voice with lyrics. We’re going to have a voice with lyrics, so angle brackets are required. We’ll add some real music later; for now let’s just put in some dummy notes and lyrics. If you’ve forgotten how to add lyrics you may wish to review \addlyrics in Setting simple songs.

\score {
  <<
    \new Staff = "singer" <<
      \new Voice = "vocal" { c'1 }
      \addlyrics { And }
    >>
    \new PianoStaff = "piano" <<
      \new Staff = "upper" { c'1 }
      \new Staff = "lower" { c'1 }
    >>
  >>
  \layout { }
}

Now we have a lot more details. We have the singer’s staff: it contains a Voice (in LilyPond, this term refers to a set of notes, not necessarily vocal notes – for example, a violin generally plays one voice) and some lyrics. We also have a piano staff: it contains an upper staff (right hand) and a lower staff (left hand), although the lower staff has yet to be given a bass clef.

At this stage, we could start filling in notes. Inside the curly braces next to \new Voice = "vocal", we could start writing

\relative {
  r4 d''8\noBeam g, c4 r
}

But if we did that, the \score section would get pretty long, and it would be harder to understand what was happening. So let’s use variables instead. These were introduced at the end of the previous section, remember? To ensure the contents of the text variable are interpreted as lyrics we preface them with \lyricmode. Like \addlyrics, this switches the input mode to lyrics. Without that, LilyPond would try to interpret the contents as notes, which would generate errors. (Several other input modes are available, see Input modes.)

So, adding a few notes and a bass clef for the left hand, we now have a piece of real music:

melody = \relative { r4 d''8\noBeam g, c4 r }
text   = \lyricmode { And God said, }
upper  = \relative { <g' d g,>2~ <g d g,> }
lower  = \relative { b,2 e }

\score {
  <<
    \new Staff = "singer" <<
      \new Voice = "vocal" { \melody }
      \addlyrics { \text }
    >>
    \new PianoStaff = "piano" <<
      \new Staff = "upper" { \upper }
      \new Staff = "lower" {
        \clef "bass"
        \lower
      }
    >>
  >>
  \layout { }
}

When writing (or reading) a \score section, just take it slowly and carefully. Start with the outer level, then work on each smaller level. It also really helps to be strict with indentation – make sure that each item on the same level starts on the same horizontal position in your text editor.

参见

Notation Reference: Structure of a score.

3.1.3 Nesting music expressions

It is not essential to declare all staves at the beginning; they may be introduced temporarily at any point. This is particularly useful for creating ossia sections – see ossia. Here is a simple example showing how to introduce a new staff temporarily for the duration of three notes:

\new Staff {
  \relative {
    r4 g'8 g c4 c8 d |
    e4 r8
    <<
      { f8 c c }
      \new Staff {
        f8 f c
      }
    >>
    r4 |
  }
}

Note that the size of the clef is the same as a clef printed following a clef change – slightly smaller than the clef at the beginning of the line. This is usual for clefs printed in the middle of a line.

The ossia section may be placed above the staff as follows:

\new Staff = "main" {
  \relative {
    r4 g'8 g c4 c8 d |
    e4 r8
    <<
      { f8 c c }
      \new Staff \with {
        alignAboveContext = "main"
      } { f8 f c }
    >>
    r4 |
  }
}

This example uses \with, which will be explained more fully later. It is a means of modifying the default behavior of a single Staff. Here it says that the new staff should be placed above the staff called “main” instead of the default position which is below.

参见

Ossia are often written without clef and without time signature and are usually in a smaller font. These require further commands which have not yet been introduced. See Size of objects, and Ossia staves.

3.1.4 Structure of a note entry

A note entry in LilyPond consists of a pitch, followed by a duration, optionally followed by one or more ‘post-events’. LilyPond post-events add things such as articulations, fingerings, string numbers, slurs, ties and explanatory text.

The pitch may be explicitly defined using the current LilyPond input language as described in Note names in other languages. The pitch may be omitted. If the pitch is omitted, the pitch of a current note will be the same as the pitch of the previous note in the input file, see Durations. Note that neither r nor s is a pitch.

The duration includes a number and optionally one or more dots. If a duration is not explicitly defined, the duration of a current note will be the same as the duration of the previous note, chord, rest, or spacer rest, see Durations.

Post-events follow the note to which they are attached. Suppose we want to have an eighth note c’ with a fingering of 1, a tenuto articulation, a slur beginning with the note, a tie beginning with the note, and a text annotation. This can be accomplished as shown.

{ c'8-1--(~^\markup{"text annotation"} c' d') }

参见

Learning Manual: Ties and slurs, Articulations and dynamics, Adding text.

Notation Reference: Pitches, Rhythms, Expressive marks.

3.1.5 On the un-nestedness of brackets and ties

You have already met a number of different types of bracket and bracket-like constructs in writing the input file to LilyPond. These obey different rules which can be confusing at first. Let’s first review the different types of brackets and bracket-like constructs.

To these we should add other constructs which generate lines between or across notes: ties (marked by a tilde, ~), tuplets written as \tuplet x/y { … }, and grace notes written as \grace { … }.

Outside LilyPond, the conventional use of brackets requires the different types to be properly nested, like this, << [ { ( … ) } ] >>, with the closing brackets being encountered in exactly the opposite order to the opening brackets. This is a requirement for the three types of bracket described by the word ‘Encloses’ in the table above – they must nest properly. However, the remaining bracket-like constructs, described with the word ‘Marks’ in the table above together with ties and tuplets, do not have to nest properly with any of the brackets or bracket-like constructs. In fact, these are not brackets in the sense that they enclose something – they are simply markers to indicate where something starts and ends.

So, for example, a phrasing slur can start before a manually inserted beam and end before the end of the beam – not very musical, perhaps, but possible:

\relative { g'8\( a b[ c b\) a] g4 }

In general, different kinds of brackets, bracket-like constructs, and those implied by tuplets, ties and grace notes, may be mixed freely. This example shows a beam extending into a tuplet (line 1), a slur extending into a tuplet (line 2), a beam and a slur extending into a tuplet, a tie crossing two tuplets, and a phrasing slur extending out of a tuplet (lines 3 and 4).

\relative {
  r16[ g' \tuplet 3/2 { r16 e'8] }
  g,16( a \tuplet 3/2 { b16 d) e }
  g,8[( a \tuplet 3/2 { b8 d) e~] } |
  \tuplet 5/4 { e32\( a, b d e } a4.\)
}

3.2 Voices contain music

Singers need voices to sing, and so does LilyPond. The actual music for all instruments in a score is contained in Voices – the most fundamental of all LilyPond’s concepts.

3.2.1 I’m hearing Voices

The lowest, most fundamental or innermost layers in a LilyPond score are called ‘Voice contexts’ or just ‘Voices’ for short. Voices are sometimes called ‘layers’ in other notation packages.

In fact, a Voice layer or context is the only one which can contain music. If a Voice context is not explicitly declared one is created automatically, as we saw at the beginning of this chapter. Some instruments such as an Oboe can play only one note at a time. Music written for such instruments requires just a single voice. Instruments which can play more than one note at a time like the piano will often require multiple voices to encode the different concurrent notes and rhythms they are capable of playing.

A single voice can contain many notes in a chord, of course, so when exactly are multiple voices needed? Look first at this example of four chords:

\relative {
  \key g \major
  <d' g>4 <d fis> <d a'> <d g>
}

This can be expressed using just the single angle bracket chord symbols, < … >, and for this just a single voice is needed. But suppose the F-sharp were actually an eighth-note followed by an eighth-note G, a passing note on the way to the A? Now we have two notes which start at the same time but have different durations: the quarter-note D and the eighth-note F-sharp. How are these to be coded? They cannot be written as a chord because all the notes in a chord must have the same duration. And they cannot be written as two sequential notes as they need to start at the same time. This is when two voices are required.

Let us see how this is done in LilyPond input syntax.

The easiest way to enter fragments with more than one voice on a staff is to enter each voice as a sequence (with { … }), and combine them simultaneously with angle brackets, << … >>. The fragments must also be separated with double backward slashes, \\, to place them in separate voices. Without these, the notes would be entered into a single voice, which would usually cause errors. This technique is particularly suited to pieces of music which are largely homophonic with occasional short sections of polyphony.

Here’s how we split the chords above into two voices and add both the passing note and a slur:

\relative {
  \key g \major
  %    Voice = "1"             Voice = "2"
  << { g'4 fis8( g) a4 g } \\ { d4 d d d }  >>
}

Notice how the stems of the second voice now point down.

Here’s another simple example:

\relative {
  \key d \minor
  %    Voice = "1"           Voice = "2"
  << { r4 g' g4. a8 }   \\ { d,2 d4 g }       >> |
  << { bes4 bes c bes } \\ { g4 g g8( a) g4 } >> |
  << { a2. r4 }         \\ { fis2. s4 }       >> |
}

It is not necessary to use a separate << \\ >> construct for each bar. For music with few notes in each bar this layout can help the legibility of the code, but if there are many notes in each bar it may be better to split out each voice separately, like this:

<<
  \key d \minor
  \relative { % Voice = "1"
    r4 g' g4. a8 |
    bes4 bes c bes |
    a2. r4 |
  } \\
  \relative { % Voice = "2"
    d'2 d4 g |
    g4 g g8( a) g4 |
    fis2. s4 |
  }
>>

This example has just two voices, but the same construct may be used to encode three or more voices by adding more back-slash separators.

The Voice contexts bear the names "1", "2", etc. The first contexts set the outer voices, the highest voice in context "1" and the lowest voice in context "2". The inner voices go in contexts "3" and "4". In each of these contexts, the vertical direction of slurs, stems, ties, dynamics etc., is set appropriately.

\new Staff \relative {
  % Main voice
  c'16 d e f
  %  Voice = "1"   Voice = "2"             Voice = "3"
  << { g4 f e } \\ { r8 e4 d c8~ } >> |
  << { d2 e }   \\ { c8 b16 a b8 g~ 2 } \\ { s4 b c2 } >> |
}

If you prefer entering the voices in a different order, like top to bottom, you can specify the respective voice numbers in front of one << … >> construct using the \voices command, like

\new Staff \relative {
  % Main voice
  c'16 d e f
  %  Voice = "1"   Voice = "2"
  << { g4 f e } \\ { r8 e4 d c8~ } >> |
  \voices 1,3,2
  %  Voice = "1"   Voice = "3"    Voice = "2"
  << { d2 e }   \\ { s4 b c2 } \\ { c8 b16 a b8 g~ 2 } >> |
}

These voices are all separate from the main voice that contains the notes just outside the << … >> construct. Let’s call this the simultaneous construct. Slurs and ties may only connect notes within the same voice, so slurs and ties cannot go into or out of a simultaneous construct. Conversely, parallel voices from separate simultaneous constructs on the same staff are the same voice. Other voice-related properties also carry across simultaneous constructs. Here is the same example, with different colors and note heads for each voice. Note that changes in one voice do not affect other voices, but they do persist in the same voice later. Note also that tied notes may be split across the same voices in two constructs, shown here in the blue triangle voice.

\new Staff \relative {
  % Main voice
  c'16 d e f
  <<  % Bar 1
    {
      \voiceOneStyle
      g4 f e
    }
  \\
    {
      \voiceTwoStyle
      r8 e4 d c8~
    }
  >> |
  <<  % Bar 2
     % Voice 1 continues
    { d2 e }
  \\
     % Voice 2 continues
    { c8 b16 a b8 g~ 2 }
  \\
    {
      \voiceThreeStyle
      s4 b c2
    }
  >> |
}

The commands \voiceXXXStyle are mainly intended for use in educational documents such as this one. They modify the color of the note head, the stem and the beams, and the style of the note head, so that the voices may be easily distinguished. Voice one is set to red diamonds, voice two to blue triangles, voice three to green crossed circles, and voice four (not used here) to magenta crosses; \voiceNeutralStyle (also not used here) reverts the style back to the default. We shall see later how commands like these may be created by the user. See Visibility and color of objects and Using variables for layout adjustments.

Polyphony does not change the relationship of notes within a \relative block. Each note is still calculated relative to the note immediately preceding it, or to the first note of the preceding chord. So in

\relative { noteA << < noteB noteC > \\ noteD >> noteE }

noteB is relative to noteA
noteC is relative to noteB, not noteA;
noteD is relative to noteB, not noteA or noteC;
noteE is relative to noteD, not noteA.

An alternative way, which may be clearer if the notes in the voices are widely separated, is to place a \relative command at the start of each voice:

\relative { noteA … }
<<
  \relative { < noteB noteC > … }
\\
  \relative { noteD … }
>>
\relative { noteE … }

Let us finally analyze the voices in a more complex piece of music. Here are the notes from the first two bars of the second of Chopin’s Deux Nocturnes, Op 32. This example will be used at later stages in this and the next chapter to illustrate several techniques for producing notation, so please ignore for now anything in the underlying code which looks mysterious and concentrate just on the music and the voices – the complications will all be explained in later sections.

The direction of the stems is often used to indicate the continuity of two simultaneous melodic lines. Here the stems of the highest notes are all pointing up and the stems of the lower notes are all pointing down. This is the first indication that more than one voice is required.

But the real need for multiple voices arises when notes which start at the same time have different durations. Look at the notes which start at beat three in the first bar. The A-flat is a dotted quarter note, the F is a quarter note and the D-flat is a half note. These cannot be written as a chord as all the notes in a chord must have the same duration. Neither can they be written as sequential notes, as they must start at the same time. This section of the bar requires three voices, and the normal practice would be to write the whole bar as three voices, as shown below, where we have used different note heads and colors for the three voices. Again, the code behind this example will be explained later, so ignore anything you do not understand.

Let us try to encode this music from scratch. As we shall see, this encounters some difficulties. We begin as we have learnt, using the << \\ >> construct to enter the music of the first bar in three voices:

\new Staff \relative {
  \key aes \major
  <<
    { c''2 aes4. bes8 } \\ { <ees, c>2 des } \\ { aes'2 f4 fes }
  >> |
  <c ees aes c>1 |
}

The stem directions are automatically assigned with the odd-numbered voices taking upward stems and the even-numbered voices downward ones. The stems for voices 1 and 2 are right, but the stems in voice 3 should go down in this particular piece of music. We can correct this by skipping voice three and placing the music in voice four. This could be done by simply adding another pair of \\, but we use the \voices command instead (which would also allow us to enter the voices in different order if we preferred doing that):

\new Staff \relative {
  \key aes \major
  \voices 1,2,4   % Omit Voice three
  <<  % Voice one
    { c''2 aes4. bes8 }
  \\  % Voice two
    { <ees, c>2 des }
  \\  % Voice four
    { aes'2 f4 fes }
  >> |
  <c ees aes c>1 |
}

We see that this fixes the stem direction, but the horizontal placement of notes is not what we want. LilyPond shifts the inner notes when they or their stems would collide with outer voices, but this is not appropriate for piano music. In other situations, the shifts LilyPond applies might fail to clear the collisions. LilyPond provides several ways to adjust the horizontal placing of notes. We are not quite ready yet to see how to correct this, so we shall leave this problem until a later section — see the force-hshift property in Fixing overlapping notation.

参见

Notation Reference: Multiple voices.

3.2.2 Explicitly instantiating voices

Voice contexts can also be created manually inside a << >> block to create polyphonic music, using \voiceOne … \voiceFour to indicate the required directions of stems, slurs, etc. In longer scores this method is clearer, as it permits the voices to be separated and to be given more descriptive names.

Specifically, the construct << \\ >> which we used in the previous section:

\new Staff {
  \relative {
    << { e'4 f g a } \\ { c,4 d e f } >>
  }
}

is equivalent to

\new Staff <<
  \new Voice = "1" { \voiceOne \relative { e'4 f g a } }
  \new Voice = "2" { \voiceTwo \relative { c'4 d e f } }
>>

Both of the above would produce

The \voiceXXX commands set the direction of stems, slurs, ties, articulations, text annotations, augmentation dots of dotted notes, and fingerings. \voiceOne and \voiceThree make these objects point upwards, while \voiceTwo and \voiceFour make them point downwards. These commands also generate a horizontal shift for each voice when this is required to avoid clashes of note heads. The command \oneVoice reverts the settings back to the normal values for a single voice.

Let us see in some simple examples exactly what effect \oneVoice, \voiceOne and voiceTwo have on markup, ties, slurs, and dynamics:

\relative {
  % Default behavior or behavior after \oneVoice
  c'4 d8~ 8 e4( f | g4 a) b-> c |
}

\relative {
  \voiceOne
  c'4 d8~ 8 e4( f | g4 a) b-> c |
  \oneVoice
  c,4 d8~ 8 e4( f | g4 a) b-> c |
}

\relative {
  \voiceTwo
  c'4 d8~ 8 e4( f | g4 a) b-> c |
  \oneVoice
  c,4 d8~ 8 e4( f | g4 a) b-> c |
}

Now let’s look at four different ways to notate the same passage of polyphonic music, each of which is advantageous in different circumstances, using the example from the previous section.

An expression that appears directly inside a << >> belongs to the main voice (but, note, not in a << \\ >> construct). This is useful when extra voices appear while the main voice is playing. Here is a more correct rendition of our example. The red diamond-shaped notes demonstrate that the main melody is now in a single voice context, permitting a phrasing slur to be drawn over them.

\new Staff \relative {
  \voiceOneStyle
  % This section is homophonic
  c'16^( d e f
  % Start simultaneous section of three voices
  <<
    % Continue the main voice in parallel
    { g4 f e | d2 e) | }
    % Initiate second voice
    \new Voice {
      % Set stems, etc., down
      \voiceTwo
      r8 e4 d c8~ | 8 b16 a b8 g~ 2 |
    }
    % Initiate third voice
    \new Voice {
      % Set stems, etc, up
      \voiceThree
      s2. | s4 b c2 |
    }
  >>
}

The \voices command can also be used for continuing a main voice into the simultaneous construct:

\new Staff \relative {
  \new Voice = "main" {
    \voiceOneStyle
    % This section is homophonic
    c'16^( d e f
    % Start simultaneous section of three voices
    \voices "main",2,3
    <<
      % Continue the main voice in parallel
      { g4 f e | d2 e) | }
      % Initiate second voice
    \\
      % Set stems, etc., down
      { r8 e4 d c8~ | 8 b16 a b8 g~ 2 | }
    \\
      % Initiate third voice
      % Set stems, etc, up
      { s2. | s4 b c2 | }
    >>
  }
}

More deeply nested polyphony constructs are possible, and if a voice appears only briefly this might be a more natural way to typeset the music:

\new Staff \relative {
  c'16^( d e f
  <<
    { g4 f e | d2 e) | }
    \new Voice {
      \voiceTwo
      r8 e4 d c8~ |
      <<
        { c8 b16 a b8 g~ 2 | }
        \new Voice {
          \voiceThree
          s4 b c2 |
        }
      >>
    }
  >>
}

This method of nesting new voices briefly is useful when only small sections of the music are polyphonic, but when the whole staff is largely polyphonic it can be clearer to use multiple voices throughout, using spacing notes to step over sections where the voice is silent, as here:

\new Staff \relative <<
  % Initiate first voice
  \new Voice {
    \voiceOne
    c'16^( d e f g4 f e | d2 e) |
  }
  % Initiate second voice
  \new Voice {
    % Set stems, etc, down
    \voiceTwo
    s4 r8 e4 d c8~ | 8 b16 a b8 g~ 2 |
  }
  % Initiate third voice
  \new Voice {
    % Set stems, etc, up
    \voiceThree
    s1 | s4 b c2 |
  }
>>

Note columns

Closely spaced notes in a chord, or notes occurring at the same time in different voices, are arranged in two, occasionally more, columns to prevent the note heads overlapping. These are called note columns. There are separate columns for each voice, and the currently specified voice-dependent shift is applied to the note column if there would otherwise be a collision. This can be seen in the example above. In bar 2 the C in voice two is shifted to the right relative to the D in voice one, and in the final chord the C in voice three is also shifted to the right relative to the other notes.

The \shiftOn, \shiftOnn, \shiftOnnn, and \shiftOff commands specify the degree to which notes and chords of the voice should be shifted if a collision would otherwise occur. By default, the outer voices (normally voices one and two) have \shiftOff specified, while the inner voices (three and four) have \shiftOn specified. When a shift is applied, voices one and three are shifted to the right and voices two and four to the left.

\shiftOnn and \shiftOnnn define further shift levels which may be specified temporarily to resolve collisions in complex situations – see Real music example.

A note column can contain just one note (or chord) from a voice with stems up and one note (or chord) from a voice with stems down. If notes from two voices which have their stems in the same direction are placed at the same position and both voices have no shift or the same shift specified, the error message “This voice needs a voiceXx or shiftXx setting” will be produced.

参见

Learning Manual: Moving objects.

Notation Reference: Multiple voices.

3.2.3 Voices and vocals

Vocal music presents a special difficulty: we need to combine two expressions – notes and lyrics.

You have already seen the \addlyrics{} command, which handles simple scores well. However, this technique is quite limited. For more complex music, you must introduce the lyrics in a Lyrics context using \new Lyrics and explicitly link the lyrics to the notes with \lyricsto{}, using the name assigned to the Voice.

<<
  \new Voice = "one" {
    \relative {
      \autoBeamOff
      \time 2/4
      c''4 b8. a16 | g4. f8 | e4 d | c2 |
    }
  }
  \new Lyrics \lyricsto "one" {
    No more let | sins and | sor -- rows | grow. |
  }
>>

Note that the lyrics must be linked to a Voice context, not a Staff context. This is a case where it is necessary to create Staff and Voice contexts explicitly.

The automatic beaming which LilyPond uses by default works well for instrumental music, but not so well for music with lyrics, where beaming is either not required at all or is used to indicate melismata in the lyrics. In the example above we use the command \autoBeamOff to turn off the automatic beaming.

Let us reuse the earlier example from Judas Maccabæus to illustrate this more flexible technique. We first recast it to use variables so the music and lyrics can be separated from the staff structure. We also introduce a ChoirStaff bracket. The lyrics themselves must be introduced with \lyricmode to ensure they are interpreted as lyrics rather than music.

global = { \key f \major \time 6/8 \partial 8 }

SopOneMusic = \relative {
  c''8 | c8([ bes)] a a([ g)] f | f'4. b, | c4.~ 4
}
SopOneLyrics = \lyricmode {
  Let | flee -- cy flocks the | hills a -- dorn, __
}
SopTwoMusic = \relative {
  r8 | r4. r4 c'8 | a'8([ g)] f f([ e)] d | e8([ d)] c bes'
}
SopTwoLyrics = \lyricmode {
  Let | flee -- cy flocks the | hills a -- dorn,
}

\score {
  \new ChoirStaff <<
    \new Staff <<
      \new Voice = "SopOne" {
        \global
        \SopOneMusic
      }
      \new Lyrics \lyricsto "SopOne" {
        \SopOneLyrics
      }
    >>
    \new Staff <<
      \new Voice = "SopTwo" {
        \global
        \SopTwoMusic
      }
      \new Lyrics \lyricsto "SopTwo" {
        \SopTwoLyrics
      }
    >>
  >>
}

This is the basic structure of all vocal scores. More staves may be added as required, more voices may be added to the staves, more verses may be added to the lyrics, and the variables containing the music can easily be placed in separate files should they become too long.

Here is an example of the first line of a hymn with four verses, set for SATB. In this case the words for all four parts are the same. Note how we use variables to separate the music notation and words from the staff structure. See too how a variable, which we have chosen to call ‘keyTime’, is used to hold several commands for use within the two staves. In other examples this is often called ‘global’.

keyTime = { \key c \major \time 4/4 \partial 4 }

SopMusic   = \relative { c'4 | e4. e8 g4  g    | a4   a   g  }
AltoMusic  = \relative { c'4 | c4. c8 e4  e    | f4   f   e  }
TenorMusic = \relative {  e4 | g4. g8 c4.   b8 | a8 b c d e4 }
BassMusic  = \relative {  c4 | c4. c8 c4  c    | f8 g a b c4 }

VerseOne =
  \lyricmode { E -- | ter -- nal fa -- ther, | strong to save, }
VerseTwo   =
  \lyricmode { O | Christ, whose voice the | wa -- ters heard, }
VerseThree =
  \lyricmode { O | Ho -- ly Spi -- rit, | who didst brood }
VerseFour  =
  \lyricmode { O | Tri -- ni -- ty of | love and pow'r }

\score {
  \new ChoirStaff <<
    \new Staff <<
      \clef "treble"
      \new Voice = "Sop"  { \voiceOne \keyTime \SopMusic }
      \new Voice = "Alto" { \voiceTwo \AltoMusic }
      \new Lyrics \lyricsto "Sop" { \VerseOne   }
      \new Lyrics \lyricsto "Sop" { \VerseTwo   }
      \new Lyrics \lyricsto "Sop" { \VerseThree }
      \new Lyrics \lyricsto "Sop" { \VerseFour  }
    >>
    \new Staff <<
      \clef "bass"
      \new Voice = "Tenor" { \voiceOne \keyTime \TenorMusic }
      \new Voice = "Bass"  { \voiceTwo \BassMusic }
    >>
  >>
}

参见

Notation Reference: Vocal music.

3.3 Contexts and engravers

Contexts and engravers have been mentioned informally in earlier sections; we now must look at these concepts in more detail, as they are important in the fine-tuning of LilyPond output.

3.3.1 Contexts explained

When music is printed, many notational elements which do not appear explicitly in the input file must be added to the output. For example, compare the input and output of the following example:

\relative { cis''4 cis2. | a4 a2. | }

The input is rather sparse, but in the output, bar lines, accidentals, clef, and time signature have been added. When LilyPond interprets the input the musical information is parsed from left to right, similar to the way a performer reads the score. While reading the input, the program remembers where measure boundaries are, and which pitches require explicit accidentals. This information must be held on several levels. For example, an accidental affects only a single staff, while a bar line must be synchronized across the entire score.

Within LilyPond, these rules and bits of information are grouped in Contexts. We have already introduced the Voice context. Others are the Staff and Score contexts. Contexts are hierarchical to reflect the hierarchical nature of a musical score. For example: a Staff context can contain many Voice contexts, and a Score context can contain many Staff contexts.

Each context has the responsibility for enforcing some notation rules, creating some notation objects and maintaining the associated properties. For example, the Voice context may introduce an accidental and then the Staff context maintains the rule to show or suppress the accidental for the remainder of the measure.

As another example, the synchronization of bar lines is, by default, handled in the Score context. However, in some music we may not want the bar lines to be synchronized – consider a polymetric score in 4/4 and 3/4 time. In such cases, we must modify the default settings of the Score and Staff contexts.

For very simple scores, contexts are created implicitly, and you need not be aware of them. For larger pieces, such as anything with more than one staff, they must be created explicitly to make sure that you get as many staves as you need, and that they are in the correct order. For typesetting pieces with specialized notation, it is usual to modify existing, or even to define totally new, contexts.

In addition to the Score, Staff and Voice contexts there are contexts which fit between the score and staff levels to control staff groups, such as the PianoStaff and ChoirStaff contexts. There are also alternative staff and voice contexts, and contexts for lyrics, percussion, fret boards, figured bass, etc.

The names of all context types are formed from one or more words, each word being capitalized and joined immediately to the preceding word with no hyphen or underscore, e.g., GregorianTranscriptionStaff.

参见

Notation Reference: Contexts explained.

3.3.2 Creating contexts

In an input file, a score block (introduced with a \score command) contains a single music expression; but it can also contain associated output definitions too – either a \layout block, a \midi block or both. The Score context is usually left to be created automatically when the interpretation of that music expression starts.

For scores with only one voice and one staff, the Voice and Staff contexts may also be left to be created automatically, but for more complex scores it is necessary to create them by hand. The simplest command that does this is \new. It is prepended to a music expression, for example

\new type music-expression

where type is a context name (like Staff or Voice). This command creates a new context, and starts interpreting the music-expression within that context.

You have seen many practical examples which created new Staff and Voice contexts in earlier sections, but to remind you how these commands are used in practice, here’s an annotated real-music example:

\score {  % start of single compound music expression
  <<  % start of simultaneous staves section
    \time 2/4
    \new Staff {  % create RH staff
      \clef "treble"
      \key g \minor
      \new Voice {  % create voice for RH notes
        \relative {  % start of RH notes
          d''4 ees16 c8. |
          d4 ees16 c8. |
        }  % end of RH notes
      }  % end of RH voice
    }  % end of RH staff
    \new Staff <<  % create LH staff; needs two simultaneous voices
      \clef "bass"
      \key g \minor
      \new Voice {  % create LH voice one
        \voiceOne
        \relative {  % start of LH voice one notes
          g8 <bes d> ees, <g c> |
          g8 <bes d> ees, <g c> |
        }  % end of LH voice one notes
      }  % end of LH voice one
      \new Voice {  % create LH voice two
        \voiceTwo
        \relative {  % start of LH voice two notes
          g4 ees |
          g4 ees |
        }  % end of LH voice two notes
      }  % end of LH voice two
    >>  % end of LH staff
  >>  % end of simultaneous staves section
}  % end of single compound music expression

(Note how all the statements which open a block with either a curly bracket, {, or double angle brackets, <<, are indented by two further spaces, and the corresponding closing bracket is indented by exactly the same amount. While this is not required, following this practice will greatly reduce the number of ‘unmatched bracket’ errors, and is strongly recommended. It enables the structure of the music to be seen at a glance, and any unmatched brackets will be obvious. Note too how the LH staff is created using double angle brackets because it requires two voices for its music, whereas the RH staff is created with a single music expression surrounded by curly brackets because it requires only one voice.)

The \new command may also give an identifying name to the context to distinguish it from other contexts of the same type,

\new type = id music-expression

Note the distinction between the name of the context type, Staff, Voice, etc, and the identifying name of a particular instance of that type, which can be any sequence of letters invented by the user. Digits and spaces can also be used in the identifying name, but then it has to be placed in quotes, i.e. \new Staff = "MyStaff 1" music-expression. The identifying name is used to refer back to that particular instance of a context. We saw this in use in the section on lyrics, see Voices and vocals.

参见

Notation Reference: Creating and referencing contexts.

3.3.3 Engravers explained

Every mark on the printed output of a score produced by LilyPond is produced by an Engraver. Thus there is an engraver to print staves, one to print note heads, one for stems, one for beams, etc, etc. In total there are over 120 such engravers! Fortunately, for most scores it is not necessary to know about more than a few, and for simple scores you do not need to know about any.

Engravers live and operate in Contexts. Engravers such as the Metronome_mark_engraver, whose action and output apply to the score as a whole, operate in the highest level context – the Score context.

The Clef_engraver and Key_engraver are to be found in every Staff Context, as different staves may require different clefs and keys.

The Note_heads_engraver and Stem_engraver live in every Voice context, the lowest level context of all.

Each engraver processes the particular objects associated with its function, and maintains the properties that relate to that function. These properties, like the properties associated with contexts, may be modified to change the operation of the engraver or the appearance of those elements in the printed score.

Engravers all have compound names formed from words which describe their function. Just the first word is capitalized, and the remainder are joined to it with underscores. Thus the Staff_symbol_engraver is responsible for creating the lines of the staff, the Clef_engraver determines and sets the pitch reference point on the staff by drawing a clef symbol.

Here are some of the most common engravers together with their function. You will see it is usually easy to guess the function from the name, or vice versa.

We shall see later how the output of LilyPond can be changed by modifying the action of Engravers.

参见

Internals reference: Engravers and Performers.

3.3.4 Modifying context properties

Contexts are responsible for holding the values of a number of context properties. Many of them can be changed to influence the interpretation of the input and so change the appearance of the output. They are changed by the \set command. This takes the form

\set ContextName.propertyName = #value

Where the ContextName is usually Score, Staff or Voice. It may be omitted, in which case the current context (typically Voice) is assumed.

The names of context properties consist of words joined together with no hyphens or underscores, all except the first having a capital letter. Here are a few examples of some commonly used ones. There are many more.

where a Boolean is either True (#t) or False (#f), an Integer is a positive whole number, a Real is a positive or negative decimal number, and text is enclosed in double apostrophes. Note the occurrence of hash signs, (#), in two different places – as part of the Boolean value before the t or f, and before value in the \set statement. So when a Boolean is being entered you need to code two hash signs, e.g., ##t.

Before we can set any of these properties we need to know in which context they operate. Sometimes this is obvious, but occasionally it can be tricky. If the wrong context is specified, no error message is produced, but the expected action will not take place. For example, the clefGlyph clearly lives in the Staff context, since it is the staff’s clef glyph that is to be changed. In this example the first staff’s clef is printed correctly, but not the second – which prints the default treble clef instead of the expected bass (or F) clef – because we omitted the context name.

<<
  \new Staff \relative {
    \set Staff.clefGlyph = "clefs.C"
    c''2 c
  }
  \new Staff \relative {
    \set clefGlyph = "clefs.F"  % Wrong!
    d'2 d
  }
>>

Remember the default context name is Voice, so the second \set command set the property clefGlyph in the Voice context to clefs.F, but as LilyPond does not look for any such property in the Voice context, no further action took place. This is not an error, and no error message is logged in the log file.

Similarly, if the property name is mis-spelt no error message is produced, and clearly the expected action cannot be performed. In fact, you can set any (fictitious) ‘property’ using any name you like in any context that exists by using the \set command. But if the name is not known to LilyPond it will not cause any action to be taken. Some text editors with special support for LilyPond input files document property names with bullets when you hover them with the mouse, like JEdit with LilyPondTool, or highlight unknown property names differently, like ConTEXT. If you do not use an editor with such features, it is recommended to check the property name in the Internals Reference: see Tunable context properties, or Contexts.

The clefGlyph property will take effect only if it is set in the Staff context, but some properties can be set in more than one context. For example, the property extraNatural is by default set to ##t (true) for all staves. If it is set to ##f (false) in one particular Staff context it applies just to the accidentals on that staff. If it is set to false in the Score context it applies to all staves.

So this turns off extra naturals in one staff:

<<
  \new Staff \relative {
    aeses'2 aes
  }
  \new Staff \relative {
    \set Staff.extraNatural = ##f
    aeses'2 aes
  }
>>

and this turns them off in all staves:

<<
  \new Staff \relative {
    aeses'2 aes
  }
  \new Staff \relative {
    \set Score.extraNatural = ##f
    aeses'2 aes
  }
>>

As another example, if clefTransposition is set in the Score context this immediately changes the value of the transposition in all current staves and sets a new default value which will be applied to all staves.

The opposite command, \unset, effectively removes the property from the context, which causes most properties to revert to their default value. Usually \unset is not required as a new \set command will achieve what is wanted.

The \set and \unset commands can appear anywhere in the input file and will take effect from the time they are encountered until the end of the score or until the property is \set or \unset again. Let’s try changing the font size, which affects the size of the note heads (among other things) several times. The change is from the default value, not the most recently set value.

\relative {
  c'4 d
  % make note heads smaller
  \set fontSize = #-4
  e4 f |
  % make note heads larger
  \set fontSize = #2.5
  g4 a
  % return to default size
  \unset fontSize
  b4 c |
}

We have now seen how to set the values of several different types of property. Note that integers and numbers are always preceded by a hash sign, #, while a true or false value is specified by ##t and ##f, with two hash signs. A text property should be enclosed in double quotation signs, as above, although we shall see later that text can actually be specified in a much more general way by using the very powerful \markup command.

Setting context properties with \with

The default value of context properties may be set at the time the context is created. Sometimes this is a clearer way of setting a property value if it is to remain fixed for the duration of the context. When a context is created with a \new command it may be followed immediately by a \with { … } block in which the default property values are set. For example, if we wish to suppress the printing of extra naturals for the duration of a staff we would write:

\new Staff \with { extraNatural = ##f }

like this:

<<
  \new Staff {
    \relative {
      gisis'4 gis aeses aes
    }
  }
  \new Staff \with { extraNatural = ##f } {
    \relative {
      gisis'4 gis aeses aes
    }
  }
>>

Properties set in this way may still be changed dynamically using \set and returned to the default value set in the \with block with \unset.

So if the fontSize property is set in a \with clause it sets the default value of the font size. If it is later changed with \set, this new default value may be restored with the \unset fontSize command.

Setting context properties with \context

The values of context properties may be set in all contexts of a particular type, such as all Staff contexts, with a single command. The context type is identified by using its type name, like Staff, prefixed by a back-slash: \Staff. The statement which sets the property value is the same as that in a \with block, introduced above. It is placed in a \context block within a \layout block. Each \context block will affect all contexts of the type specified throughout the \score or \book block in which the \layout block appears. Here is an example to show the format:

\score {
  \new Staff {
    \relative {
      cisis''4 e d cis
    }
  }
  \layout {
    \context {
      \Staff
      extraNatural = ##t
    }
  }
}

If the property override is to be applied to all staves within the score:

\score {
  <<
    \new Staff {
      \relative {
        gisis'4 gis aeses aes
      }
    }
    \new Staff {
      \relative {
        gisis'4 gis aeses aes
      }
    }
  >>
  \layout {
    \context {
      \Score extraNatural = ##f
    }
  }
}

Context properties set in this way may be overridden for particular instances of contexts by statements in a \with block, and by \set commands embedded in music statements.

参见

Notation Reference: Changing context default settings. The set command.

Internals Reference: Contexts, Tunable context properties.

3.3.5 Adding and removing engravers

We have seen that contexts each contain several engravers, each of which is responsible for producing a particular part of the output, like bar lines, staves, note heads, stems, etc. If an engraver is removed from a context, it can no longer produce its output. This is a crude way of modifying the output, but it can sometimes be useful.

Changing a single context

To remove an engraver from a single context we use the \with command placed immediately after the context creation command, as in the previous section.

As an illustration, let’s repeat an example from the previous section with the staff lines removed. Remember that the staff lines are produced by the Staff_symbol_engraver.

\new Staff \with {
  \remove "Staff_symbol_engraver"
}
\relative {
  c'4 d
  \set fontSize = #-4  % make note heads smaller
  e4 f |
  \set fontSize = #2.5  % make note heads larger
  g4 a
  \unset fontSize  % return to default size
  b4 c |
}

Engravers can also be added to individual contexts. The command to do this is

\consists Engraver_name,

placed inside a \with block. Some vocal scores have an ambitus placed at the beginning of a staff to indicate the range of notes in that staff – see ambitus. The ambitus is produced by the Ambitus_engraver, which is not normally included in any context. If we add it to the Voice context, it calculates the range from that voice only:

\new Staff <<
  \new Voice \with {
    \consists "Ambitus_engraver"
  } {
    \relative {
      \voiceOne
      c''4 a b g
    }
  }
  \new Voice {
    \relative {
      \voiceTwo
      c'4 e d f
    }
  }
>>

but if we add the ambitus engraver to the Staff context, it calculates the range from all the notes in all the voices on that staff:

\new Staff \with {
  \consists "Ambitus_engraver"
}
<<
  \new Voice {
    \relative {
      \voiceOne
      c''4 a b g
    }
  }
  \new Voice {
    \relative {
      \voiceTwo
      c'4 e d f
    }
  }
>>

Changing all contexts of the same type

The examples above show how to remove or add engravers to individual contexts. It is also possible to remove or add engravers to every context of a specific type by placing the commands in the appropriate context in a \layout block. For example, if we wanted to show an ambitus for every staff in a four-staff score, we could write

\score {
  <<
    \new Staff {
      \relative {
        c''4 a b g
      }
    }
    \new Staff {
      \relative {
        c'4 a b g
      }
    }
    \new Staff {
      \clef "G_8"
      \relative {
        c'4 a b g
      }
    }
    \new Staff {
      \clef "bass"
      \relative {
        c4 a b g
      }
    }
  >>
  \layout {
    \context {
      \Staff
      \consists "Ambitus_engraver"
    }
  }
}

The values of context properties may also be set for all contexts of a particular type by including the \set command in a \context block in the same way.

参见

Notation Reference: Modifying context plug-ins, Changing context default settings.

已知的问题和警告

The Stem_engraver and Beam_engraver attach their objects to note heads. If the Note_heads_engraver is removed no note heads are produced and therefore no stems or beams are created either.

3.4 Extending the templates

You’ve read the tutorial, you know how to write music, you understand the fundamental concepts. But how can you get the staves that you want? Well, you can find lots of templates (see Templates) which may give you a start. But what if you want something that isn’t covered there? Read on.

3.4.1 Soprano and cello

Start off with the template that seems closest to what you want to end up with. Let’s say that you want to write something for soprano and cello. In this case, we would start with the ‘Notes and lyrics’ template (for the soprano part).

\version "2.23.3"

melody = \relative {
  \clef "treble"
  \key c \major
  \time 4/4
  a4 b c d
}

text = \lyricmode {
  Aaa Bee Cee Dee
}

\score {
  <<
    \new Voice = "one" {
      \autoBeamOff
      \melody
    }
    \new Lyrics \lyricsto "one" \text
  >>
  \layout { }
  \midi { }
}

Now we want to add a cello part. Let’s look at the ‘Notes only’ example:

\version "2.23.3"

melody = \relative {
  \clef "treble"
  \key c \major
  \time 4/4
  a4 b c d
}

\score {
  \new Staff \melody
  \layout { }
  \midi { }
}

We don’t need two \version commands. We’ll need the melody section. We don’t want two \score sections – if we had two \scores, we’d get the two parts separately. We want them together, as a duet. Within the \score section, we don’t need two \layout or \midi.

If we simply cut and paste the melody section, we would end up with two melody definitions. This would not generate an error, but the second one would be used for both melodies. So let’s rename them to make them distinct. We’ll call the section for the soprano sopranoMusic and the section for the cello celloMusic. While we’re doing this, let’s rename text to be sopranoLyrics. Remember to rename both instances of all these names – both the initial definition (the melody = \relative { part) and the name’s use (in the \score section).

While we’re doing this, let’s change the cello part’s staff – celli normally use bass clef. We’ll also give the cello some different notes.

\version "2.23.3"

sopranoMusic = \relative {
  \clef "treble"
  \key c \major
  \time 4/4
  a4 b c d
}

sopranoLyrics = \lyricmode {
  Aaa Bee Cee Dee
}

celloMusic = \relative {
  \clef "bass"
  \key c \major
  \time 4/4
  d4 g fis8 e d4
}

\score {
  <<
    \new Voice = "one" {
      \autoBeamOff
      \sopranoMusic
    }
    \new Lyrics \lyricsto "one" \sopranoLyrics
  >>
  \layout { }
  \midi { }
}

This is looking promising, but the cello part won’t appear in the score – we haven’t used it in the \score section. If we want the cello part to appear under the soprano part, we need to add

\new Staff \celloMusic

underneath the soprano stuff. We also need to add << and >> around the music – that tells LilyPond that there’s more than one thing (in this case, two Staves) happening at once. The \score looks like this now:

\score {
  <<
  <<
    \new Voice = "one" {
      \autoBeamOff
      \sopranoMusic
    }
    \new Lyrics \lyricsto "one" \sopranoLyrics
  >>
  \new Staff \celloMusic
  >>
  \layout { }
  \midi { }
}

This looks a bit messy; the indentation is messed up now. That is easily fixed. Here’s the complete soprano and cello template.

sopranoMusic = \relative {
  \clef "treble"
  \key c \major
  \time 4/4
  a4 b c d
}

sopranoLyrics = \lyricmode {
  Aaa Bee Cee Dee
}

celloMusic = \relative {
  \clef "bass"
  \key c \major
  \time 4/4
  d4 g fis8 e d4
}

\score {
  <<
    <<
      \new Voice = "one" {
        \autoBeamOff
        \sopranoMusic
      }
      \new Lyrics \lyricsto "one" \sopranoLyrics
    >>
    \new Staff \celloMusic
  >>
  \layout { }
  \midi { }
}

参见

The starting templates can be found in the ‘Templates’ appendix, see Single staff templates.

3.4.2 Four-part SATB vocal score

Most vocal scores of music written for four-part mixed choir with orchestral accompaniment such as Mendelssohn’s Elijah or Handel’s Messiah have the choral music and words on four staves, one for each of SATB, with a piano reduction of the orchestral accompaniment underneath. Here’s an example from Handel’s Messiah:

The nearest copy-and-edit template to this layout is SATB vocal score and automatic piano reduction – but we need to change the layout and add a piano accompaniment which is not derived automatically from the vocal parts. The variables holding the music and words for the vocal parts are fine, but we shall need to add variables for the piano reduction.

The order in which the contexts appear in the ChoirStaff of the template do not correspond with the order in the vocal score shown above. We need to rearrange them so there are four staves with the words written directly underneath the notes for each part. All the voices should be \voiceOne, which is the default, so the \voiceXXX commands should be removed. We also need to specify the tenor clef for the tenors. The way in which lyrics are specified in the template has not yet been encountered so we need to use the method with which we are familiar. We should also add the names of each staff.

Doing this gives for our ChoirStaff:

\new ChoirStaff <<
  \new Staff = "sopranos"
  \with { instrumentName = "Soprano" }
  <<
    \new Voice = "sopranos" {
      \global
      \sopranoMusic
    }
  >>
  \new Lyrics \lyricsto "sopranos" {
    \sopranoWords
  }
  \new Staff = "altos"
  \with { instrumentName = "Alto" }
  <<
    \new Voice = "altos" {
      \global
      \altoMusic
    }
  >>
  \new Lyrics \lyricsto "altos" {
    \altoWords
  }
  \new Staff = "tenors"
  \with { instrumentName = "Tenor" }
  <<
    \new Voice = "tenors" {
      \global
      \tenorMusic
    }
  >>
  \new Lyrics \lyricsto "tenors" {
    \tenorWords
  }
  \new Staff = "basses"
  \with { instrumentName = "Bass" }
  <<
    \new Voice = "basses" {
      \global
      \bassMusic
    }
  >>
  \new Lyrics \lyricsto "basses" {
    \bassWords
  }
>>  % end ChoirStaff

Next we must work out the piano part. This is easy - we just pull out the piano part from the ‘Solo piano’ template:

\new PianoStaff \with { instrumentName = "Piano  " }
<<
  \new Staff = "upper" \upper
  \new Staff = "lower" \lower
>>

and add the variable definitions for upper and lower.

The ChoirStaff and PianoStaff must be combined using angle brackets as we want them to be stacked one above the other:

<<  % combine ChoirStaff and PianoStaff one above the other
  \new ChoirStaff <<
    \new Staff = "sopranos" <<
      \new Voice = "sopranos" {
        \global
        \sopranoMusic
      }
    >>
    \new Lyrics \lyricsto "sopranos" {
      \sopranoWords
     }
    \new Staff = "altos" <<
      \new Voice = "altos" {
        \global
        \altoMusic
      }
    >>
    \new Lyrics \lyricsto "altos" {
      \altoWords
    }
    \new Staff = "tenors" <<
      \clef "G_8"  % tenor clef
      \new Voice = "tenors" {
        \global
        \tenorMusic
      }
    >>
    \new Lyrics \lyricsto "tenors" {
      \tenorWords
    }
    \new Staff = "basses" <<
      \clef "bass"
      \new Voice = "basses" {
        \global
        \bassMusic
      }
    >>
    \new Lyrics \lyricsto "basses" {
      \bassWords
    }
  >>  % end ChoirStaff

  \new PianoStaff \with { instrumentName = "Piano" }
  <<
    \new Staff = "upper" \upper
    \new Staff = "lower" \lower
  >>
>>

Combining all these together and adding the music for the three bars of the example above gives:

global = { \key d \major \time 4/4 }
sopranoMusic = \relative {
  \clef "treble"
  r4 d''2 a4 | d4. d8 a2 | cis4 d cis2 |
}
sopranoWords = \lyricmode {
  Wor -- thy | is the lamb | that was slain |
}
altoMusic = \relative {
  \clef "treble"
  r4 a'2 a4 | fis4. fis8 a2 | g4 fis fis2 |
}
altoWords = \sopranoWords
tenorMusic = \relative {
  \clef "G_8"
  r4 fis'2 e4 | d4. d8 d2 | e4 a, cis2 |
}
tenorWords = \sopranoWords
bassMusic = \relative {
  \clef "bass"
  r4 d'2 cis4 | b4. b8 fis2 | e4 d a'2 |
}
bassWords = \sopranoWords
upper = \relative {
  \clef "treble"
  \global
  r4 <a' d fis>2 <a e' a>4 |
  <d fis d'>4. <d fis d'>8 <a d a'>2 |
  <g cis g'>4 <a d fis> <a cis e>2 |
}
lower = \relative {
  \clef "bass"
  \global
  <d, d'>4 <d d'>2 <cis cis'>4 |
  <b b'>4. <b' b'>8 <fis fis'>2 |
  <e e'>4 <d d'> <a' a'>2 |
}

\score {
  <<  % combine ChoirStaff and PianoStaff in parallel
    \new ChoirStaff <<
      \new Staff = "sopranos"
      \with { instrumentName = "Soprano" }
      <<
        \new Voice = "sopranos" {
          \global
          \sopranoMusic
        }
      >>
      \new Lyrics \lyricsto "sopranos" {
        \sopranoWords
      }
      \new Staff = "altos"
      \with { instrumentName = "Alto" }
      <<
        \new Voice = "altos" {
          \global
          \altoMusic
        }
      >>
      \new Lyrics \lyricsto "altos" {
        \altoWords
      }
      \new Staff = "tenors"
      \with { instrumentName = "Tenor" }
      <<
        \new Voice = "tenors" {
          \global
          \tenorMusic
        }
      >>
      \new Lyrics \lyricsto "tenors" {
        \tenorWords
      }
      \new Staff = "basses"
      \with { instrumentName = "Bass" }
      <<
        \new Voice = "basses" {
          \global
          \bassMusic
        }
      >>
      \new Lyrics \lyricsto "basses" {
        \bassWords
      }
    >>  % end ChoirStaff

    \new PianoStaff
    \with { instrumentName = "Piano  " }
    <<
      \new Staff = "upper" \upper
      \new Staff = "lower" \lower
    >>
  >>
}

3.4.3 Building a score from scratch

After gaining some facility with writing LilyPond code, you may find that it is easier to build a score from scratch rather than modifying one of the templates. You can also develop your own style this way to suit the sort of music you like. Let’s see how to put together the score for an organ prelude as an example.

We begin with a header section. Here go the title, name of composer, etc, then come any variable definitions, and finally the score block. Let’s start with these in outline and fill in the details later.

We’ll use the first two bars of Bach’s prelude based on Jesu, meine Freude which is written for two manuals and pedal organ. You can see these two bars of music at the bottom of this section. The top manual part has two voices, the lower and pedal organ one each. So we need four music definitions and one to define the time signature and key:

\version "2.23.3"
\header {
  title = "Jesu, meine Freude"
  composer = "J S Bach"
}
keyTime = { \key c \minor \time 4/4 }
ManualOneVoiceOneMusic = { s1 }
ManualOneVoiceTwoMusic = { s1 }
ManualTwoMusic = { s1 }
PedalOrganMusic = { s1 }

\score {
}

For now we’ve just used a spacer note, s1, instead of the real music. We’ll add that later.

Next let’s see what should go in the score block. We simply mirror the staff structure we want. Organ music is usually written on three staves, one for each manual and one for the pedals. The manual staves should be bracketed together, so we need to use a PianoStaff for them. The first manual part needs two voices and the second manual part just one.

\new PianoStaff <<
  \new Staff = "ManualOne" <<
    \new Voice {
      \ManualOneVoiceOneMusic
    }
    \new Voice {
      \ManualOneVoiceTwoMusic
    }
  >>  % end ManualOne Staff context
  \new Staff = "ManualTwo" <<
    \new Voice {
      \ManualTwoMusic
    }
  >>  % end ManualTwo Staff context
>>  % end PianoStaff context

Next we need to add a staff for the pedal organ. This goes underneath the PianoStaff, but it must be simultaneous with it, so we need angle brackets around the two. Missing these out would generate an error in the log file. It’s a common mistake which you’ll make sooner or later! Try copying the final example at the end of this section, remove these angle brackets, and compile it to see what errors it generates.

<<  % PianoStaff and Pedal Staff must be simultaneous
  \new PianoStaff <<
    \new Staff = "ManualOne" <<
      \new Voice {
        \ManualOneVoiceOneMusic
      }
      \new Voice {
        \ManualOneVoiceTwoMusic
      }
    >>  % end ManualOne Staff context
    \new Staff = "ManualTwo" <<
      \new Voice {
        \ManualTwoMusic
      }
    >>  % end ManualTwo Staff context
  >>  % end PianoStaff context
  \new Staff = "PedalOrgan" <<
    \new Voice {
      \PedalOrganMusic
    }
  >>
>>

It is not necessary to use the simultaneous construct << … >> for the manual two staff and the pedal organ staff, since they contain only one music expression, but it does no harm, and always using angle brackets after \new Staff is a good habit to cultivate in case there are multiple voices. The opposite is true for Voices: these should habitually be followed by braces { … } in case your music is coded in several variables which need to run consecutively.

Let’s add this structure to the score block, and adjust the indenting. We also add the appropriate clefs, ensure stems, ties and slurs in each voice on the upper staff point to the right direction with \voiceOne and \voiceTwo, and enter the key and time signature to each staff using our predefined variable, \keyTime.

\score {
  <<  % PianoStaff and Pedal Staff must be simultaneous
    \new PianoStaff <<
      \new Staff = "ManualOne" <<
        \keyTime  % set key and time signature
        \clef "treble"
        \new Voice {
          \voiceOne
          \ManualOneVoiceOneMusic
        }
        \new Voice {
          \voiceTwo
          \ManualOneVoiceTwoMusic
        }
      >>  % end ManualOne Staff context
      \new Staff = "ManualTwo" <<
        \keyTime
        \clef "bass"
        \new Voice {
          \ManualTwoMusic
        }
      >>  % end ManualTwo Staff context
    >>  % end PianoStaff context
    \new Staff = "PedalOrgan" <<
      \keyTime
      \clef "bass"
      \new Voice {
        \PedalOrganMusic
      }
    >>  % end PedalOrgan Staff
  >>
}  % end Score context

The above layout of the organ staves is almost perfect; however, there is a slight defect which is not visible by looking at just a single system: The distance of the pedal staff to the left hand staff should behave approximately the same as the right hand staff to the left hand staff. In particular, the stretchability of staves in a PianoStaff context is limited (so that the distance between the staves for the left and right hand can’t become too large), and the pedal staff should behave similarly.

Stretchability of staves can be controlled with the staff-staff-spacing property of the VerticalAxisGroup ‘graphical object’ (commonly called ‘grob’s within the lilypond documentation) – don’t worry about the details right now; this is fully explained later. For the curious, have a look at Overview of modifying properties. In this case, we want to modify the stretchability sub-property only. Any values not changed will use the default value. Again, for the curious, you can find the default values for the staff-staff-spacing property in file ‘scm/define-grobs.scm’ by looking up the definition of the default-staff-staff-spacing property of the VerticalAxisGroup grob. The value for stretchability below is taken from the definition of the StaffGrouper grob (in file ‘scm/define-grobs.scm’) so that the values are identical.

\score {
  <<  % PianoStaff and Pedal Staff must be simultaneous
    \new PianoStaff <<
      \new Staff = "ManualOne" <<
        \keyTime  % set key and time signature
        \clef "treble"
        \new Voice {
          \voiceOne
          \ManualOneVoiceOneMusic
        }
        \new Voice {
          \voiceTwo
          \ManualOneVoiceTwoMusic
        }
      >>  % end ManualOne Staff context
      \new Staff = "ManualTwo" \with {
        \override VerticalAxisGroup.staff-staff-spacing.stretchability = 5
      } <<
        \keyTime
        \clef "bass"
        \new Voice {
          \ManualTwoMusic
        }
      >>  % end ManualTwo Staff context
    >>  % end PianoStaff context
    \new Staff = "PedalOrgan" <<
      \keyTime
      \clef "bass"
      \new Voice {
        \PedalOrganMusic
      }
    >>  % end PedalOrgan Staff
  >>
}  % end Score context

That completes the structure. Any three-staff organ music will have a similar structure, although the number of voices may vary. All that remains now is to add the music, and combine all the parts together.

\header {
  title = "Jesu, meine Freude"
  composer = "J S Bach"
}
keyTime = { \key c \minor \time 4/4 }
ManualOneVoiceOneMusic = \relative {
  g'4 g f ees |
  d2 c |
}
ManualOneVoiceTwoMusic = \relative {
  ees'16 d ees8~ 16 f ees d c8 d~ d c~ |
  8 c4 b8 c8. g16 c b c d |
}
ManualTwoMusic = \relative {
  c'16 b c8~ 16 b c g a8 g~ 16 g aes ees |
  f16 ees f d g aes g f ees d ees8~ 16 f ees d |
}
PedalOrganMusic = \relative {
  r8 c16 d ees d ees8~ 16 a, b g c b c8 |
  r16 g ees f g f g8 c,2 |
}

\score {
  <<  % PianoStaff and Pedal Staff must be simultaneous
    \new PianoStaff <<
      \new Staff = "ManualOne" <<
        \keyTime  % set key and time signature
        \clef "treble"
        \new Voice {
          \voiceOne
          \ManualOneVoiceOneMusic
        }
        \new Voice {
          \voiceTwo
          \ManualOneVoiceTwoMusic
        }
      >>  % end ManualOne Staff context
      \new Staff = "ManualTwo" \with {
        \override VerticalAxisGroup.staff-staff-spacing.stretchability = 5
      } <<
        \keyTime
        \clef "bass"
        \new Voice {
          \ManualTwoMusic
        }
      >>  % end ManualTwo Staff context
    >>  % end PianoStaff context
    \new Staff = "PedalOrgan" <<
      \keyTime
      \clef "bass"
      \new Voice {
        \PedalOrganMusic
      }
    >>  % end PedalOrgan Staff context
  >>
}  % end Score context

参见

Music Glossary: system.

3.4.4 Saving typing with variables and functions

By this point, you’ve seen this kind of thing:

hornNotes = \relative { c''4 b dis c }

\score {
  {
    \hornNotes
  }
}

You may even realize that this could be useful in minimalist music:

fragmentA = \relative { a'4 a8. b16 }
fragmentB = \relative { a'8. gis16 ees4 }

violin = \new Staff {
  \fragmentA \fragmentA |
  \fragmentB \fragmentA |
}

\score {
  {
    \violin
  }
}

However, you can also use these variables (also known as macros, or user-defined commands) for tweaks:

dolce = \markup { \italic \bold dolce }

centreText = { \once \override TextScript.self-alignment-X = #CENTER }

fthenp =_\markup {
  \dynamic f \italic \small { 2nd } \hspace #0.1 \dynamic p
}

violin = \relative {
  \repeat volta 2 {
    c''4._\dolce b8 a8 g a b |
    \centreText
    c4.^"hi there!" d8 e f g d |
    c4.\fthenp b8 c4 c-. |
  }
}

\score {
  {
    \violin
  }
}

These variables are obviously useful for saving typing. But they’re worth considering even if you only use them once – they reduce complexity. Let’s look at the previous example without any variables. It’s a lot harder to read, especially the last line.

violin = \relative {
  \repeat volta 2 {
    c''4._\markup { \italic \bold dolce } b8 a8 g a b |
    \once \override TextScript.self-alignment-X = #CENTER
    c4.^"hi there!" d8 e f g d |
    c4._\markup {
      \dynamic f \italic \small { 2nd } \hspace #0.1 \dynamic p
    }
    b8 c4 c-. |
  }
}

Remember ‘post-events’? Articulations, fingerings, anything that has to be added after a note (see Structure of a note entry), often prefixed with a dash or a direction modifier. In fact, even these events can be stored in a variable – in which case the usual curly braces are not wanted, since you wouldn’t use them between a note and its articulations.

If such a definition includes a prefix, then the variable can be used directly after the note – unless you want to change its direction, in which case you can insert a modifier that will take precedence:

articulationVar = -^-!

artEsprVar = \articulationVar ^\espressivo

\relative c' {
  c\articulationVar d e2^\articulationVar
  d2\artEsprVar c_\artEsprVar
}

So far we’ve seen static substitution – when LilyPond sees \centreText, it replaces it with the stuff that we’ve defined it to be (ie the stuff to the right of centreText=).

LilyPond can handle non-static substitution, too (you can think of these as functions).

padText =
#(define-music-function
     (padding)
     (number?)
   #{
     \once \override TextScript.padding = #padding
   #})

\relative {
  c''4^"piu mosso" b a b
  \padText #1.8
  c4^"piu mosso" b a b
  \padText #2.6
  c4^"piu mosso" b a b
}

Using variables is also a good way to reduce work if the LilyPond input syntax changes (see Updating files with convert-ly). If you have a single definition (such as \dolce) for all your input files (see Style sheets), then if the syntax changes, you only need to update your single \dolce definition, instead of making changes throughout every ‘.ly’ file.

3.4.5 Scores and parts

In orchestral music, all notes are printed twice. Once in a part for the musicians, and once in a full score for the conductor. Variables can be used to avoid double work. The music is entered once, and stored in a variable. The contents of that variable is then used to generate both the part and the full score.

It is convenient to define the notes in a special file. For example, suppose that the file ‘horn-music.ly’ contains the following part of a horn/bassoon duo

hornNotes = \relative {
  \time 2/4
  r4 f8 a | cis4 f | e4 d |
}

Then, an individual part is made by putting the following in a file

\include "horn-music.ly"

\header {
  instrument = "Horn in F"
}

{
 \transpose f c' \hornNotes
}

The line

\include "horn-music.ly"

substitutes the contents of ‘horn-music.ly’ at this position in the file, so hornNotes is defined afterwards. The command \transpose f c' indicates that the argument, being \hornNotes, should be transposed by a fifth upwards. Sounding f is denoted by notated c', which corresponds with the tuning of a normal French Horn in F. The transposition can be seen in the following output

In ensemble pieces, one of the voices often does not play for many measures. This is denoted by a special rest, the multi-measure rest. It is entered with a capital R followed by a duration (1 for a whole note, 2 for a half note, etc.). By multiplying the duration, longer rests can be constructed. For example, this rest takes 3 measures in 2/4 time

R2*3

When printing the part, multi-measure rests must be compressed. There is a music function available to do this:

\compressMMRests { ... }

Applying this to hornNotes gives:

The score is made by combining all of the music together. Assuming that the other voice is in bassoonNotes in the file ‘bassoon-music.ly’, a score is made with

\include "bassoon-music.ly"
\include "horn-music.ly"

<<
  \new Staff \hornNotes
  \new Staff \bassoonNotes
>>

leading to

参见

Learning Manual: Organizing pieces with variables.

Notation Reference: Transpose, Writing parts, Full measure rests, Including LilyPond files.

4 Tweaking output

This chapter discusses how to modify output. LilyPond is extremely configurable; virtually every fragment of output may be changed.

4.1 Tweaking basics

4.1.1 Introduction to tweaks

‘Tweaking’ is a LilyPond term for the various methods available to the user for modifying the actions taken during interpretation of the input file and modifying the appearance of the printed output. Some tweaks are very easy to use; others are more complex. But taken together the methods available for tweaking permit almost any desired appearance of the printed music to be achieved.

In this section we cover the basic concepts required to understand tweaking. Later we give a variety of ready-made commands which can simply be copied to obtain the same effect in your own scores, and at the same time we show how these commands may be constructed so that you may learn how to develop your own tweaks.

Before starting on this Chapter you may wish to review the section Contexts and engravers, as Contexts, Engravers, and the Properties contained within them are fundamental to understanding and constructing Tweaks.

4.1.2 Objects and interfaces

Tweaking involves modifying the internal operation and structures of the LilyPond program, so we must first introduce some terms which are used to describe those internal operations and structures.

The term ‘Object’ is a generic term used to refer to the multitude of internal structures built by LilyPond during the processing of an input file. So when a command like \new Staff is encountered a new object of type Staff is constructed. That Staff object then holds all the properties associated with that particular staff, for example, its name and its key signature, together with details of the engravers which have been assigned to operate within that staff’s context. Similarly, there are objects to hold the properties of all other contexts, such as Voice objects, Score objects, Lyrics objects, as well as objects to represent all notational elements such as bar lines, note heads, ties, dynamics, etc. Every object has its own set of property values.

Some types of object are given special names. Objects which represent items of notation on the printed output such as note heads, stems, slurs, ties, fingering, clefs, etc are called ‘Layout objects’, often known as ‘Graphical Objects’, or ‘Grobs’ for short. These are still objects in the generic sense above, and so they too all have properties associated with them, such as their position, size, color, etc.

Some layout objects are still more specialized. Phrasing slurs, crescendo hairpins, ottava marks, and many other grobs are not localized in a single place – they have a starting point, an ending point, and maybe other properties concerned with their shape. Objects with an extended shape like these are called ‘Spanners’.

Spanners cannot be tweaked after their creation. This includes both StaffSymbol and LedgerLineSpanner which continue throughout the score, except if they are terminated by the \stopStaff command and then recreated using \startStaff command.

What is more, there are ‘abstract’ grobs which do not print anything of their own, but rather collect, position and manage other grobs. Common examples for this are DynamicLineSpanner, BreakAlignment, NoteColumn, VerticalAxisGroup, NonMusicalPaperColumn and similar. We will see how some of these are used later.

It remains to explain what ‘Interfaces’ are. Many objects, even though they are quite different, share common features which need to be processed in the same way. For example, all grobs have a color, a size, a position, etc, and all these properties are processed in the same way during LilyPond’s interpretation of the input file. To simplify these internal operations these common actions and properties are grouped together in an object called a grob-interface. There are many other groupings of common properties like this, each one given a name ending in interface. In total there are over 100 such interfaces. We shall see later why this is of interest and use to the user.

These, then, are the main terms relating to objects which we shall use in this chapter.

4.1.3 Naming conventions of objects and properties

We met some object naming conventions previously, in Contexts and engravers. Here for reference is a list of the most common object and property types together with the conventions for naming them and a couple of examples of some real names. We have used ‘A’ to stand for any capitalized alphabetic character and ‘aaa’ to stand for any number of lower-case alphabetic characters. Other characters are used verbatim.

As we shall see shortly, the properties of different types of object are modified by different commands, so it is useful to be able to recognize the types of objects and properties from their names.

参见

Notation Reference: Modifying properties.

4.1.4 Tweaking methods

The \override command

We have already met the commands \set and \with, used to change the properties of contexts and to remove and add engravers, in Modifying context properties, and Adding and removing engravers. We must now introduce some more important commands.

The command to change the properties of layout objects is \override. Because this command has to modify internal properties deep within LilyPond its syntax is not as simple as the commands you have used so far. It needs to know precisely which property of which object in which context has to be modified, and what its new value is to be. Let’s see how this is done.

The general syntax of this command is:

\override Context.LayoutObject.layout-property = #value

This will set the property with the name layout-property of the layout object with the name LayoutObject, which is a member of the Context context, to the value value.

The Context may be omitted (and usually is) when the required context is unambiguously implied and is one of lowest level contexts, i.e., Voice, ChordNames or Lyrics, and we shall omit it in many of the following examples. We shall see later when it must be specified.

Later sections deal comprehensively with properties and their values, see Types of properties. But in this section we shall use just a few simple properties and values which are easily understood in order to illustrate the format and use of these commands.

LilyPond’s primary expressions are musical items like notes and durations, as well as strings and markups. More specific expressions like numbers, symbols and lists are processed in ‘Scheme mode’, which is invoked by prefixing the value with ‘#’. For more information about Scheme mode, see LilyPond Scheme syntax.

\override is the most common command used in tweaking, and most of the rest of this chapter will be directed to presenting examples of how it is used. Here is a simple example to change the color of the note head:

\relative {
  c'4 d
  \override NoteHead.color = "red"
  e4 f |
  \override NoteHead.color = "green"
  g4 a b c |
}

The \revert command

Once overridden, the property retains its new value until it is overridden again or a \revert command is encountered. The \revert command has the following syntax and causes the value of the property to revert to its original default value; note, not its previous value if several \override commands have been issued.

\revert Context.LayoutObject.layout-property

Again, just like Context in the \override command, Context is often not needed. It will be omitted in many of the following examples. Here we revert the color of the note head to the default value for the final two notes:

\relative {
  c'4 d
  \override NoteHead.color = "red"
  e4 f |
  \override NoteHead.color = "green"
  g4 a
  \revert NoteHead.color
  b4 c |
}

The \once prefix

\override, \revert, \set, and \unset commands may be prefixed with \once. This causes such a command to be effective only during the current musical moment before the property reverts back to its previous value (this can be different from the default if another \override is still in effect). Using the same example, we can change the color of a single note like this:

\relative {
  c'4 d
  \override NoteHead.color = "red"
  e4 f |
  \once \override NoteHead.color = "green"
  g4 a
  \once \revert NoteHead.color
  b c |
  \revert NoteHead.color
  f2 c |
}

The \once prefix may also be used in front of many predefined commands to limit their effect to one musical moment:

\relative {
  c'4( d)
  \once \slurDashed
  e4( f) |
  g4( a)
  \once \hideNotes
  b( c) |
}

The \overrideProperty command

There is another form of the override command, \overrideProperty, which is occasionally required. We mention it here for completeness, but for details see Difficult tweaks.

The \tweak command

The final tweaking command which is available is \tweak. This should be used when several objects occur at the same musical moment, but you only want to change the properties of selected ones, such as a single note within a chord. Using \override would affect all the notes within a chord, whereas \tweak affects just the following item in the input stream.

Here’s an example. Suppose we wish to change the size of the middle note head (the E) in a C major chord. Let’s first see what \once \override would do:

\relative {
  <c' e g>4
  \once \override NoteHead.font-size = #-3
  <c e g>4
  <c e g>4
}

We see the override affects all the note heads in the chord. This is because all the notes of a chord occur at the same musical moment, and the action of \once is to apply the override to all layout objects of the type specified which occur at the same musical moment as the \override command itself.

The \tweak command operates in a different way. It acts on the immediately following item in the input stream. In its simplest form, it is effective only on objects which are created directly from the following item, essentially note heads and articulations.

So to return to our example, the size of the middle note of a chord would be changed in this way:

\relative {
  <c' e g>4
  <c \tweak font-size #-3 e g>4
}

Note that the syntax of \tweak is different from that of the \override command. The context should not be specified; in fact, it would generate an error to do so. Both context and layout object are implied by the following item in the input stream. Note also that an equals sign should not be present. So the simple form of the \tweak command is

\tweak layout-property #value

A \tweak command can also be used to modify just one in a series of articulations, as shown here:

a'4^"Black"
  -\tweak color "red" ^"Red"
  -\tweak color "green" _"Green"

Note that the \tweak command must be preceded by an articulation mark since the tweaked expression needs to be applied as an articulation itself. In case of multiple direction overrides (^ or _), the leftmost override wins since it is applied last.

Objects such as stems and accidentals are created later, and not directly from the following event. It is still possible to use \tweak on such indirectly created objects by explicitly naming the layout object, provided that LilyPond can trace its origin back to the original event:

<\tweak Accidental.color "red"   cis''4
 \tweak Accidental.color "green" es''
 g''>

This long form of the \tweak command can be described as

\tweak LayoutObject.layout-property #value

The \tweak command must also be used to change the appearance of one of a set of nested tuplets which begin at the same musical moment. In the following example, the long tuplet bracket and the first of the three short brackets begin at the same musical moment, so any \override command would apply to both of them. In the example, \tweak is used to distinguish between them. The first \tweak command specifies that the long tuplet bracket is to be placed above the notes and the second one specifies that the tuplet number is to be printed in red on the first short tuplet bracket.

\relative c'' {
  \tweak direction #up
  \tuplet 3/4 {
    \tweak color "red"
    \tuplet 3/2 { c8[ c c] }
    \tuplet 3/2 { c8[ c c] }
    \tuplet 3/2 { c8[ c c] }
  }
}

If nested tuplets do not begin at the same moment, their appearance may be modified in the usual way with \override commands:

\relative {
  \tuplet 3/2 { c'8[ c c] }
  \once \override TupletNumber.text = #tuplet-number::calc-fraction-text
  \tuplet 3/2 {
    c8[ c]
    c8[ c]
    \once \override TupletNumber.transparent = ##t
    \tuplet 3/2 { c8[ c c] }
    \tuplet 3/2 { c8[ c c] }
  }
}

参见

Notation Reference: The tweak command.

The \single prefix

Suppose we wanted to emphasize particular note heads by coloring them red and increasing their size, and to make it easy suppose also we have defined a function to do this:

emphNoteHead = {
  \override NoteHead.color = "red"
  \override NoteHead.font-size = 2
}
\relative {
  c''4 a \once \emphNoteHead f d |
}

The \once prefix works fine to emphasize single notes or complete chords, but it cannot be used to emphasize a single note within a chord. Earlier we have seen how \tweak can be used to do this, see The \tweak command. But \tweak cannot be used with a function; that’s where \single comes in:

emphNoteHead = {
  \override NoteHead.color = "red"
  \override NoteHead.font-size = 2
}
\relative {
   <c'' a \single \emphNoteHead f d>4
}

In summary, \single converts overrides into tweaks so when there are several objects at the same point in musical time (like noteheads in a chord), \single will only affect a single one, the one generated by the immediately following music expression, in contrast to \once which will affect all of those objects.

By using \single in this way any shorthand function containing just overrides may be applied to individual notes in a chord. However, \single does not convert \revert, \set or \unset into tweaks.

参见

Learning Manual: The \tweak command, Using variables for layout adjustments.

4.2 The Internals Reference manual

4.2.1 Properties of layout objects

Suppose you have a slur in a score which, to your mind, appears too thin and you’d like to draw it a little heavier. How do you go about doing this? You know from the statements earlier about the flexibility of LilyPond that such a thing should be possible, and you would probably guess that an \override command would be needed. But is there a heaviness property for a slur, and if there is, how might it be modified? This is where the Internals Reference manual comes in. It contains all the information you might need to construct this and all other \override commands.

Before we look at the Internals Reference a word of warning. This is a reference document, which means there is little or no explanation contained within it: its purpose is to present information precisely and concisely. This means it might look daunting at first sight. Don’t worry! The guidance and explanation presented here will enable you to extract the information from the Internals Reference for yourself with just a little practice.

Let’s use a concrete example with a simple fragment of real music:

{
  \key es \major
  \time 6/8
  \relative {
    r4 bes'8 bes[( g]) g |
    g8[( es]) es d[( f]) as |
    as8 g
  }
  \addlyrics {
    The man who | feels love's sweet e -- | mo -- tion
  }
}

Suppose now that we decide we would like the slurs to be a little heavier. Is this possible? The slur is certainly a layout object, so the question is, ‘Is there a property belonging to a slur which controls the heaviness?’ To answer this we must look in the Internals Reference, or IR for short.

The IR for the version of LilyPond you are using may be found on the LilyPond website at https://lilypond.org. Go to the documentation page and click on the Internals Reference link. For learning purposes you should use the standard HTML version, not the ‘one big page’ or the PDF. For the next few paragraphs to make sense you will need to actually do this as you read.

Under the heading Top you will see five links. Select the link to the Backend, which is where information about layout objects is to be found. There, under the heading Backend, select the link to All layout objects. The page that appears lists all the layout objects used in your version of LilyPond, in alphabetic order. Select the link to Slur, and the properties of Slurs are listed.

An alternative way of finding this page is from the Notation Reference. On one of the pages that deals with slurs you may find a link to the Internals Reference. This link will take you directly to this page, but if you have an idea about the name of the layout object to be tweaked, it is easier to go straight to the IR and search there.

This Slur page in the IR tells us first that Slur objects are created by the Slur_engraver. Then it lists the standard settings. Browse through them looking for a property that might control the heaviness of slurs, and you should find

thickness (number)
     1.2
     Line thickness, generally measured in line-thickness

This looks a good bet to change the heaviness. It tells us that the value of thickness is a simple number, that the default value is 1.2, and that the units are in another property called line-thickness.

As we said earlier, there are few to no explanations in the IR, but we already have enough information to try changing the slur thickness. We see that the name of the layout object is Slur, that the name of the property to change is thickness and that the new value should be a number somewhat larger than 1.2 if we are to make slurs thicker.

We can now construct the \override command by simply substituting the values we have found for the names, omitting the context. Let’s use a very large value for the thickness at first, so we can be sure the command is working. We get:

\override Slur.thickness = #5.0

Don’t forget the # preceding the new value!

The final question is, ‘Where should this command be placed?’ While you are unsure and learning, the best answer is, ‘Within the music, before the first slur and close to it.’ Let’s do that:

{
  \key es \major
  \time 6/8
  \relative {
    % Increase thickness of all following slurs from 1.2 to 5.0
    \override Slur.thickness = #5.0
    r4 bes'8 bes[( g]) g |
    g8[( es]) es d[( f]) as |
    as8 g
  }
  \addlyrics {
    The man who | feels love's sweet e -- | mo -- tion
  }
}

and we see that the slur is indeed heavier.

So this is the basic way of constructing \override commands. There are a few more complications that we shall meet in later sections, but you now know all the essentials required to make up your own – but you will still need some practice. This is provided in the examples which follow.

Finding the context

But first, what if we had needed to specify the Context? What should it be? We could guess that slurs are in the Voice context, as they are clearly closely associated with individual lines of music, but can we be sure? To find out, go back to the top of the IR page describing the Slur, where it says ‘Slur objects are created by: Slur engraver’. So slurs will be created in whichever context the Slur_engraver is in. Follow the link to the Slur_engraver page. At the very bottom it tells us that Slur_engraver is part of seven Voice contexts, including the standard voice context, Voice, so our guess was correct. And because Voice is one of the lowest level contexts which is implied unambiguously by the fact that we are entering notes, we can omit it in this location.

Overriding once only

As you can see, all the slurs are thicker in the final example above. But what if we wanted just the first slur to be thicker? This is achieved with the \once command. Placed immediately before the \override command it causes it to change only the slur which begins on the immediately following note. If the immediately following note does not begin a slur the command has no effect at all – it is not remembered until a slur is encountered, it is simply discarded. So the command with \once must be repositioned as follows:

{
  \key es \major
  \time 6/8
  \relative {
    r4 bes'8
    % Increase thickness of immediately following slur only
    \once \override Slur.thickness = #5.0
    bes8[( g]) g |
    g8[( es]) es d[( f]) as |
    as8 g
  }
  \addlyrics {
    The man who | feels love's sweet e -- | mo -- tion
  }
}

Now only the first slur is made heavier.

The \once command can also be used before the \set command.

Reverting

Finally, what if we wanted just the first two slurs to be heavier? Well, we could use two commands, each preceded by \once placed immediately before each of the notes where the slurs begin:

{
  \key es \major
  \time 6/8
  \relative {
    r4 bes'8
    % Increase thickness of immediately following slur only
    \once \override Slur.thickness = #5.0
    bes[( g]) g |
    % Increase thickness of immediately following slur only
    \once \override Slur.thickness = #5.0
    g8[( es]) es d[( f]) as |
    as8 g
  }
  \addlyrics {
    The man who | feels love's sweet e -- | mo -- tion
  }
}

or we could omit the \once command and use the \revert command to return the thickness property to its default value after the second slur:

{
  \key es \major
  \time 6/8
  \relative {
    r4 bes'8
    % Increase thickness of all following slurs from 1.2 to 5.0
    \override Slur.thickness = #5.0
    bes[( g]) g |
    g8[( es]) es
    % Revert thickness of all following slurs to default of 1.2
    \revert Slur.thickness
    d8[( f]) as |
    as8 g
  }
  \addlyrics {
    The man who | feels love's sweet e -- | mo -- tion
  }
}

The \revert command can be used to return any property changed with \override back to its default value. You may use whichever method best suits what you want to do.

That concludes our introduction to the IR, and the basic method of tweaking. Several examples follow in the later sections of this Chapter, partly to introduce you to some of the additional features of the IR, and partly to give you more practice in extracting information from it. These examples will contain progressively fewer words of guidance and explanation.

4.2.2 Properties found in interfaces

Suppose now that we wish to print the lyrics in italics. What form of \override command do we need to do this? We first look in the IR page listing ‘All layout objects’, as before, and look for an object that might control lyrics. We find LyricText, which looks right. Clicking on this shows the settable properties for lyric text. These include the font-series and font-size, but nothing that might give an italic shape. This is because the shape property is one that is common to all font objects, so, rather than including it in every layout object, it is grouped together with other similar common properties and placed in an Interface, the font-interface.

So now we need to learn how to find the properties of interfaces, and to discover what objects use these interface properties.

Look again at the IR page which describes LyricText. At the bottom of the page is a list of clickable interfaces which LyricText supports. The list has several items, including font-interface. Clicking on this brings up the properties associated with this interface, which are also properties of all the objects which support it, including LyricText.

Now we see all the user-settable properties which control fonts, including font-shape(symbol), where symbol can be set to upright, italics or caps.

You will notice that font-series and font-size are also listed there. This immediately raises the question: Why are the common font properties font-series and font-size listed under LyricText as well as under the interface font-interface but font-shape is not? The answer is that font-series and font-size are changed from their global default values when a LyricText object is created, but font-shape is not. The entries in LyricText then tell you the values for those two properties which apply to LyricText. Other objects which support font-interface will set these properties differently when they are created.

Let’s see if we can now construct the \override command to change the lyrics to italics. The object is LyricText, the property is font-shape and the value is italic. As before, we’ll omit the context.

As an aside, although it is an important one, note that some properties take values that are symbols, like italic, and must be preceded by an apostrophe, '. Symbols are then read internally by LilyPond. Note the distinction from arbitrary text strings, which would appear as "a text string"; for more details about symbols and strings, see Scheme tutorial.

So we see that the \override command needed to print the lyrics in italics is:

\override LyricText.font-shape = #'italic

This should be placed just in front of the lyrics we wish to affect, like so:

{
  \key es \major
  \time 6/8
  \relative {
    r4 bes'8 bes[( g]) g |
    g8[( es]) es d[( f]) as |
    as8 g
  }
  \addlyrics {
    \override LyricText.font-shape = #'italic
    The man who | feels love's sweet e -- | mo -- tion
  }
}

and the lyrics are all printed in italics.

参见

Extending: Scheme tutorial.

4.2.3 Types of properties

So far we have seen two types of property: number and symbol. To be valid, the value given to a property must be of the correct type and obey the rules for that type. The type of property is always shown in brackets after the property name in the IR. Here is a list of the types you may need, together with the rules for that type, and some examples. You must always add a hash symbol, #, of course, to the front of these values when they are entered in the \override command, even if the value itself already starts with #. We only give examples for constants here: if you want to compute a value using Scheme, see Calculations in Scheme.

参见

Extending: Scheme tutorial.

4.3 Appearance of objects

Let us now put what we have learned into practice with a few examples which show how tweaks may be used to change the appearance of the printed music.

4.3.1 Visibility and color of objects

In the educational use of music we might wish to print a score with certain elements omitted as an exercise for the student, who is required to supply them. As a simple example, let us suppose the exercise is to supply the missing bar lines in a piece of music. But the bar lines are normally inserted automatically. How do we prevent them printing?

Before we tackle this, let us remember that object properties are grouped in what are called interfaces – see Properties found in interfaces. This is simply to group together those properties that may be used together to tweak a graphical object – if one of them is allowed for an object, so are the others. Some objects then use the properties in some interfaces, others use them from other interfaces. The interfaces which contain the properties used by a particular grob are listed in the IR at the bottom of the page describing that grob, and those properties may be viewed by looking at those interfaces.

We explained how to find information about grobs in Properties of layout objects. Using the same approach, we go to the IR to find the layout object which prints bar lines. Going via Backend and All layout objects we find there is a layout object called BarLine. Its properties include two that control its visibility: break-visibility and stencil. Barline also supports a number of interfaces, including the grob-interface, where we find the transparent and the color properties. All of these can affect the visibility of bar lines (and, of course, by extension, many other layout objects too.) Let’s consider each of these in turn.

The stencil property

This property controls the appearance of the bar lines by specifying the symbol (glyph) which should be printed. In common with many other properties, it can be set to print nothing by setting its value to #f. Let’s try it, as before, omitting the implied Context, Voice:

\relative {
  \time 12/16
  \override BarLine.stencil = ##f
  c''4 b8 c d16 c d8 |
  g,8 a16 b8 c d4 e16 |
  e8
}

The bar lines are still printed. What is wrong? Go back to the IR and look again at the page giving the properties of BarLine. At the top of the page it says “Barline objects are created by: Bar_engraver”. Go to the Bar_engraver page. At the bottom it gives a list of Contexts in which the bar engraver operates. All of them are of the type Staff, so the reason the \override command failed to work as expected is because Barline is not in the default Voice context. If the context is specified incorrectly, the command simply does not work. No error message is produced, and nothing is logged in the log file. Let’s try correcting it by adding the correct context:

\relative {
  \time 12/16
  \override Staff.BarLine.stencil = ##f
  c''4 b8 c d16 c d8 |
  g,8 a16 b8 c d4 e16 |
  e8
}

Now the bar lines have vanished. Setting the stencil property to #f is such a frequent operation that there is a shorthand for it called \omit:

\relative {
  \time 12/16
  \omit Staff.BarLine
  c''4 b8 c d16 c d8 |
  g,8 a16 b8 c d4 e16 |
  e8
}

Note, though, that setting the stencil property to #f will cause errors when the dimensions of the object are required for correct processing. For example, errors will be generated if the stencil property of the NoteHead object is set to #f. If this is the case, you can instead use the point-stencil function, which sets the stencil to an object with zero size:

\relative {
  c''4 c
  \once \override NoteHead.stencil = #point-stencil
  c4 c
}

The break-visibility property

We see from the BarLine properties in the IR that the break-visibility property requires a vector of three booleans. These control respectively whether bar lines are printed at the end of a line, in the middle of lines, and at the beginning of lines. For our example we want all bar lines to be suppressed, so the value we need is #(#f #f #f) (also available under the name all-invisible). Let’s try that, remembering to include the Staff context. Note also that in writing this value we have ## before the opening parenthesis. One # is required as part of vector constant syntax, and the first # is required, as always, to precede the value itself in the \override command.

\relative {
  \time 12/16
  \override Staff.BarLine.break-visibility = ##(#f #f #f)
  c''4 b8 c d16 c d8 |
  g,8 a16 b8 c d4 e16 |
  e8
}

And we see this too removes all the bar lines.

The transparent property

We see from the properties specified in the grob-interface page in the IR that the transparent property is a boolean. This should be set to #t to make the grob transparent. In this next example let us make the time signature invisible rather than the bar lines. To do this we need to find the grob name for the time signature. Back to the ‘All layout objects’ page in the IR to find the properties of the TimeSignature layout object. This is produced by the Time_signature_engraver which you can check also lives in the Staff context and also supports the grob-interface. So the command to make the time signature transparent is:

\relative {
  \time 12/16
  \override Staff.TimeSignature.transparent = ##t
  c''4 b8 c d16 c d8 |
  g,8 a16 b8 c d4 e16 |
  e8
}

Again, setting the transparent property is a rather frequent operation, so we have a shorthand for it called \hide:

\relative {
  \time 12/16
  \hide Staff.TimeSignature
  c''4 b8 c d16 c d8 |
  g,8 a16 b8 c d4 e16 |
  e8
}

In either case, the time signature is gone, but this command leaves a gap where the time signature should be. Maybe this is what is wanted for an exercise for the student to fill it in, but in other circumstances a gap might be undesirable. To remove it, the stencil for the time signature should be set to #f instead:

\relative {
  \time 12/16
  \omit Staff.TimeSignature
  c''4 b8 c d16 c d8 |
  g,8 a16 b8 c d4 e16 |
  e8
}

and the difference is obvious: setting the stencil to #f (possibly via \omit) removes the object entirely; making the object transparent (which can be done using \hide) leaves it where it is, but makes it invisible.

The color property

Finally let us try making the bar lines invisible by coloring them white. (There is a difficulty with this in that the white bar line may or may not blank out the staff lines where they cross. You may see in some of the examples below that this happens unpredictably. The details of why this is so and how to control it are covered in Painting objects white. But at the moment we are learning about color, so please just accept this limitation for now.)

The grob-interface specifies that the color property value is a list, but there is no explanation of what that list should be. The list it requires is actually a list of values in internal units, but, to avoid having to know what these are, several ways are provided to specify colors. The first way is to use one of the predefined ‘CSS’ colors listed in List of colors. To set the bar lines to white we write:

\relative {
  \time 12/16
  \override Staff.BarLine.color = "white"
  c''4 b8 c d16 c d8 |
  g,8 a16 b8 c d4 e16 |
  e8
}

and again, we see the bar lines are not visible. Note that white is not preceded by an apostrophe – it is not a symbol, but a character string, mapped to a predefined list of internal values. In that regard, LilyPond’s syntax mimics the CSS language commonly used in webpages; in addition to predefined names, we can specify a hexadecimal color code:

\relative {
  \time 12/16
  \override Staff.BarLine.color = "#FFFFFF"
  c''4 b8 c d16 c d8 |
  g,8 a16 b8 c d4 e16 |
  e8
}

We could even define that color as a variable, and then use that variable as a property definition. Since it is both a LilyPond variable and a Scheme object, it can be prefixed with a backslash or with a hash character without any difference:

whiteVar = "#FFFFFF"

\relative {
  \time 12/16
  \override Staff.BarLine.color = \whiteVar
  c''4 b8 c d16 c d8 |
  \override Staff.BarLine.color = #whiteVar
  g,8 a16 b8 c d4 e16 |
  e8
}

Another way of adding colors to your score is by using a function. There are two useful functions in this regard; one is the x11-color function, which we’ll get to use shortly. The other one, the rgb-color function, closely demonstrates LilyPond’s internal logic: it takes three arguments giving the intensities of the red, green and blue colors. These take values in the range 0 to 1. So to set the color to red the value should be (rgb-color 1 0 0) and to white it should be (rgb-color 1 1 1):

\relative {
  \time 12/16
  \override Staff.BarLine.color = #(rgb-color 1 1 1)
  c''4 b8 c d16 c d8 |
  g,8 a16 b8 c d4 e16 |
  e8
}

Note that in this case the whole function call has to be enclosed in parentheses. The same can be said of the x11-color function which we just skipped over.

x11-color, again, maps predefined color names to internal values – but offers many more choices than CSS names, as you can see in List of colors). For example, the X11 set of colors includes an extensive grey scale, whose names range from black, 'grey0, to white, 'grey100, in steps of 1. Let’s illustrate this by setting all the layout objects in our example to various shades of grey:

\relative {
  \time 12/16
  \override Staff.StaffSymbol.color = #(x11-color 'grey30)
  \override Staff.TimeSignature.color = #(x11-color 'grey60)
  \override Staff.Clef.color = #(x11-color 'grey60)
  \override Voice.NoteHead.color = #(x11-color 'grey85)
  \override Voice.Stem.color = #(x11-color 'grey85)
  \override Staff.BarLine.color = #(x11-color 'grey10)
  c''4 b8 c d16 c d8 |
  g,8 a16 b8 c d4 e16 |
  e8
}

Note the contexts associated with each of the layout objects. It is important to get these right, or the commands will not work! Remember, the context is the one in which the appropriate engraver is placed. The default context for engravers can be found by starting from the layout object, going from there to the engraver which produces it, and on the engraver page in the IR it tells you in which context the engraver will normally be found.

4.3.2 Size of objects

Let us begin by looking again at the earlier example (see Nesting music expressions) which showed how to introduce a new temporary staff, as in an ossia.

\new Staff ="main" {
  \relative {
    r4 g'8 g c4 c8 d |
    e4 r8
    <<
      { f8 c c }
      \new Staff \with {
        alignAboveContext = "main" }
      { f8 f c }
    >>
    r4 |
  }
}

Ossia are normally written without clef and time signature, and are usually printed slightly smaller than the main staff. We already know now how to remove the clef and time signature – we simply set the stencil of each to #f, as follows:

\new Staff ="main" {
  \relative {
    r4 g'8 g c4 c8 d |
    e4 r8
    <<
      { f8 c c }
      \new Staff \with {
        alignAboveContext = "main"
      }
      {
        \omit Staff.Clef
        \omit Staff.TimeSignature
        { f8 f c }
      }
    >>
    r4 |
  }
}

where the extra pair of braces after the \with clause are required to ensure the enclosed overrides and music are applied to the ossia staff.

But what is the difference between modifying the staff context by using \with and modifying the stencils of the clef and the time signature with \override, or in this case \omit? The main difference is that changes made in a \with clause are made at the time the context is created, and remain in force as the default values for the duration of that context, whereas \set or \override commands embedded in the music are dynamic – they make changes synchronized with a particular point in the music. If changes are unset or reverted using \unset or \revert they return to their default values, which will be the ones set in the \with clause, or if none have been set there, the normal default values.

Some context properties can be modified only in \with clauses. These are those properties which cannot sensibly be changed after the context has been created. alignAboveContext and its partner, alignBelowContext, are two such properties – once the staff has been created its alignment is decided and it would make no sense to try to change it later.

The default values of layout object properties can also be set in \with clauses. Simply use the normal \override command leaving out the context name, since this is unambiguously defined as the context which the \with clause is modifying. If fact, an error will be generated if a context is specified in this location.

So we could replace the example above with

\new Staff ="main" {
  \relative {
    r4 g'8 g c4 c8 d |
    e4 r8
    <<
      { f8 c c }
      \new Staff \with {
        alignAboveContext = "main"
        % Don't print clefs in this staff
        \override Clef.stencil = ##f
        % Don't print time signatures in this staff
        \override TimeSignature.stencil = ##f
      }
      { f8 f c }
    >>
    r4 |
  }
}

It turns out that we can also employ the shorthands \hide and \omit for setting the transparent property and clearing the stencil here, leading to the result

\new Staff ="main" {
  \relative {
    r4 g'8 g c4 c8 d |
    e4 r8
    <<
      { f8 c c }
      \new Staff \with {
        alignAboveContext = "main"
        % Don't print clefs in this staff
        \omit Clef
        % Don't print time signatures in this staff
        \omit TimeSignature
      }
      { f8 f c }
    >>
    r4 |
  }
}

Finally we come to changing the size of layout objects.

Some layout objects are created as glyphs selected from a typeface font. These include note heads, accidentals, markup, clefs, time signatures, dynamics and lyrics. Their size is changed by modifying the font-size property, as we shall shortly see. Other layout objects such as slurs and ties – in general, spanner objects – are drawn individually, so there is no font-size associated with them. These objects generally derive their size from the objects to which they are attached, so usually there is no need to change their size manually. Still other properties such as the length of stems and bar lines, thickness of beams and other lines, and the separation of staff lines all need to be modified in special ways.

Returning to the ossia example, let us first change the font-size. We can do this in two ways. We can either change the size of the fonts of each object type, like NoteHeads with commands like

\override NoteHead.font-size = #-2

or we can change the size of all fonts by setting a special property, fontSize, using \set, or by including it in a \with clause (but without the \set).

\set fontSize = #-2

Both of these statements would cause the font size to be reduced by 2 steps from its previous value, where each step reduces or increases the size by approximately 12%.

Let’s try it in our ossia example:

\new Staff ="main" {
  \relative {
    r4 g'8 g c4 c8 d |
    e4 r8
    <<
      { f8 c c }
      \new Staff \with {
        alignAboveContext = "main"
        \omit Clef
        \omit TimeSignature
        % Reduce all font sizes by ~24%
        fontSize = #-2
      }
      { f8 f c }
    >>
    r4 |
  }
}

This is still not quite right. The note heads and flags are smaller, but the stems are too long in proportion and the staff lines are spaced too widely apart. These need to be scaled down in proportion to the font reduction. The next sub-section discusses how this is done.

4.3.3 Length and thickness of objects

Distances and lengths in LilyPond are generally measured in staff-spaces, the distance between adjacent lines in the staff, (or occasionally half staff spaces) while most thickness properties are measured in units of an internal property called line-thickness. For example, by default, the lines of hairpins are given a thickness of 1 unit of line-thickness, while the thickness of a note stem is 1.3. Note, though, that some thickness properties are different; for example, the thickness of beams is controlled by the value of the beam-thickness property, which is measured in staff-spaces.

So how are lengths to be scaled in proportion to the font size? This can be done with the help of a special function called magstep provided for exactly this purpose. It takes one argument, the change in font size (#-2 in the example above) and returns a scaling factor suitable for reducing other objects in proportion. It is used like this:

\new Staff ="main" {
  \relative {
    r4 g'8 g c4 c8 d |
    e4 r8
    <<
      { f8 c c }
      \new Staff \with {
        alignAboveContext = "main"
        \omit Clef
        \omit TimeSignature
        fontSize = #-2
        % Reduce stem length and line spacing to match
        \override StaffSymbol.staff-space = #(magstep -2)
      }
      { f8 f c }
    >>
    r4 |
  }
}

Since the length of stems and many other length-related properties are always calculated relative to the value of the staff-space property these are automatically scaled down in length too. Note that this affects only the vertical scale of the ossia – the horizontal scale is determined by the layout of the main music in order to remain synchronized with it, so it is not affected by any of these changes in size. Of course, if the scale of all the main music were changed in this way then the horizontal spacing would be affected. This is discussed later in the layout section.

This, then, completes the creation of an ossia. The sizes and lengths of all other objects may be modified in analogous ways.

For small changes in scale, as in the example above, the thickness of the various drawn lines such as bar lines, beams, hairpins, slurs, etc does not usually require global adjustment. If the thickness of any particular layout object needs to be adjusted this can be best achieved by overriding its thickness property. An example of changing the thickness of slurs was shown above in Properties of layout objects. The thickness of all drawn objects (i.e., those not produced from a font) may be changed in the same way.

4.4 Placement of objects

4.4.1 Automatic behavior

There are some objects in musical notation that belong to the staff and there are other objects that should be placed outside the staff. These are called within-staff objects and outside-staff objects respectively.

Within-staff objects are those that are located on the staff – note heads, stems, accidentals, etc. The positions of these are usually fixed by the music itself – they are vertically positioned on specific lines of the staff or are tied to other objects that are so positioned. Collisions of note heads, stems and accidentals in closely set chords are normally avoided automatically. There are commands and overrides which can modify this automatic behavior, as we shall shortly see.

Objects belonging outside the staff include things such as rehearsal marks, text and dynamic markings. LilyPond’s rule for the vertical placement of outside-staff objects is to place them as close to the staff as possible but not so close that they collide with any other object. LilyPond uses the outside-staff-priority property to determine the order in which the objects should be placed, as follows.

First, LilyPond places all the within-staff objects. Then it sorts the outside-staff objects according to their outside-staff-priority. The outside-staff objects are taken one by one, beginning with the object with the lowest outside-staff-priority, and placed so that they do not collide with any objects that have already been placed. That is, if two outside-staff grobs are competing for the same space, the one with the lower outside-staff-priority will be placed closer to the staff. If two objects have the same outside-staff-priority the one encountered first will be placed closer to the staff.

In the following example all the markup texts have the same priority (since it is not explicitly set). Note that ‘Text3’ is automatically positioned close to the staff again, nestling under ‘Text2’.

c''2^"Text1"
c''2^"Text2" |
c''2^"Text3"
c''2^"Text4" |

Staves are also positioned, by default, as closely together as possible (subject to a minimum separation). If notes project a long way towards an adjacent staff they will force the staves further apart only if an overlap of the notation would otherwise occur. The following example demonstrates this ‘nestling’ of the notes on adjacent staves:

<<
  \new Staff {
    \relative { c'4 a, }
  }
  \new Staff {
    \relative { c''''4 a, }
  }
>>

4.4.2 Within-staff objects

We have already seen how the commands \voiceXXX affect the direction of slurs, ties, fingering and everything else which depends on the direction of the stems – see Explicitly instantiating voices. These commands are essential when writing polyphonic music to permit interweaving melodic lines to be distinguished. But occasionally it may be necessary to override this automatic behavior. This can be done for whole sections of music or even for an individual note. The property which controls this behavior is the direction property of each layout object. We first explain what this does, and then introduce a number of ready-made commands which avoid your having to code explicit overrides for the more common modifications.

Some layout objects like slurs and ties curve, bend or point either up or down; others like stems and flags also move to right or left when they point up or down. This is controlled automatically when direction is set.

The direction property

The following example shows the default positioning of slurs in the first bar, with slurs starting on high notes positioned above the notes and those starting on low notes positioned below, followed by a bar with both slurs forced down, a bar with both slurs forced up, and finally a bar with both slurs reverted back to the default behavior.

a'4( g') c''( a') |
\override Slur.direction = #DOWN
a'4( g') c''( a') |
\override Slur.direction = #UP
a'4( g') c''( a') |
\revert Slur.direction
a'4( g') c''( a') |

Here we have used the constants DOWN and UP. These have the values -1 and +1 respectively, and these numerical values may be used instead. The value 0 may also be used in some cases. It is simply treated as meaning UP for slurs, but for some objects it means ‘center’. There is a constant, CENTER which has the value 0.

However, these explicit overrides are not usually used, as there are simpler equivalent predefined commands available. Here is a table of the commonest. The meaning of each is stated where it is not obvious.

The neutral/normal variants of these commands are implemented using \revert and these may not be preceded by \once. If you wish to limit the effect of the other commands (which are implemented using \override) to a single timestep, you can precede them with \once like you would do with explicit overrides.

Or, if just a single layout object needs to be forced up or down, the direction indicators, ^ or _, may be used:

a'4( g') c''( a') |
a'4^( g') c''_( a') |

Fingering

The placement of fingering on single notes can also be controlled by the direction property, but changing direction has no effect on chords. As we shall see, there are special commands which allow the fingering of individual notes of chords to be controlled, with the fingering being placed above, below, to the left or to the right of each note.

First, here’s the effect of direction on the fingering attached to single notes. The first bar shows the default behaviour, and the following two bars shows the effect of specifying DOWN and UP:

\relative {
  c''4-5 a-3 f-1 c'-5 |
  \override Fingering.direction = #DOWN
  c4-5 a-3 f-1 c'-5 |
  \override Fingering.direction = #UP
  c4-5 a-3 f-1 c'-5 |
}

However, overriding the direction property is not the easiest way of manually setting the fingering above or below the notes; using _ or ^ instead of - before the fingering number is usually preferable. Here is the previous example using this method:

\relative {
  c''4-5 a-3 f-1 c'-5 |
  c4_5 a_3 f_1 c'_5 |
  c4^5 a^3 f^1 c'^5 |
}

The direction property is ignored for chords, but the directional prefixes, _ and ^ do work. By default, the fingering is automatically placed both above and below the notes of a chord, as shown:

\relative {
  <c''-5 g-3>4
  <c-5 g-3 e-2>4
  <c-5 g-3 e-2 c-1>4
}

but this may be overridden to manually force all or any of the individual fingering numbers above or below:

\relative {
  <c''-5 g-3 e-2 c-1>4
  <c^5 g_3 e_2 c_1>4
  <c^5 g^3 e^2 c_1>4
}

Even greater control over the placement of fingering of the individual notes in a chord is possible by using the \set fingeringOrientations command. The format of this command is:

\set fingeringOrientations = #'([up] [left/right] [down])

\set is used because fingeringOrientations is a property of the Voice context, created and used by the New_fingering_engraver.

The property may be set to a list of one to three values. It controls whether fingerings may be placed above (if up appears in the list), below (if down appears), to the left (if left appears, or to the right (if right appears). Conversely, if a location is not listed, no fingering is placed there. LilyPond takes these constraints and works out the best placement for the fingering of the notes of the following chords. Note that left and right are mutually exclusive – fingering may be placed only on one side or the other, not both.

Here are a few examples:

\relative {
  \set fingeringOrientations = #'(left)
  <f'-2>4
  <c-1 e-2 g-3 b-5>4
  \set fingeringOrientations = #'(left)
  <f-2>4
  <c-1 e-2 g-3 b-5>4 |
  \set fingeringOrientations = #'(up left down)
  <f-2>4
  <c-1 e-2 g-3 b-5>4
  \set fingeringOrientations = #'(up left)
  <f-2>4
  <c-1 e-2 g-3 b-5>4 |
  \set fingeringOrientations = #'(right)
  <f-2>4
  <c-1 e-2 g-3 b-5>4
}

If the fingering seems a little crowded the font-size could be reduced. The default value can be seen from the Fingering object in the IR to be -5, so let’s try -7:

\relative {
  \override Fingering.font-size = #-7
  \set fingeringOrientations = #'(left)
  <f'-2>4
  <c-1 e-2 g-3 b-5>4
  \set fingeringOrientations = #'(left)
  <f-2>4
  <c-1 e-2 g-3 b-5>4 |
  \set fingeringOrientations = #'(up left down)
  <f-2>4
  <c-1 e-2 g-3 b-5>4
  \set fingeringOrientations = #'(up left)
  <f-2>4
  <c-1 e-2 g-3 b-5>4 |
  \set fingeringOrientations = #'(right)
  <f-2>4
  <c-1 e-2 g-3 b-5>4
}

4.4.3 Outside-staff objects

Outside-staff objects are automatically placed to avoid collisions. There are several ways to override the automatic placement if the positioning is not optimum.

The outside-staff-priority property

Objects with the lower value of the outside-staff-priority property are placed nearer to the staff, and other outside-staff objects are then raised as far as necessary to avoid collisions. The outside-staff-priority is defined in the grob-interface and so is a property of all layout objects. By default it is set to #f for all within-staff objects, and to a numerical value appropriate to each outside-staff object when the object is created. The following table shows the default numerical values for some of the commonest outside-staff objects.

Note the unusual names for some of the objects: spanner objects are automatically created to control the vertical positioning of grobs which (might) start and end at different musical moments, so changing the outside-staff-priority of the underlying grob will have no effect. For example, changing outside-staff-priority of the Hairpin object will have no effect on the vertical positioning of hairpins – you must change outside-staff-priority of the associated DynamicLineSpanner object instead. This override must be placed at the start of the spanner, which might include several linked hairpins and dynamics.

Here is an example showing the default placement of some of these.

% Set details for later Text Spanner
\override TextSpanner.bound-details.left.text
    = \markup { \small \bold Slower }
% Place dynamics above staff
\dynamicUp
% Start Ottava Bracket
\ottava #1
c''4 \startTextSpan
% Add Dynamic Text and hairpin
c''4\pp\<
c''4
% Add Text Script
c''4^Text |
c''4 c''
% Add Dynamic Text and terminate hairpin
c''4\ff c'' \stopTextSpan |
% Stop Ottava Bracket
\ottava #0
c'4 c' c' c' |

This example also shows how to create Text Spanners – text with extender lines above a section of music. The spanner extends from the \startTextSpan command to the \stopTextSpan command, and the format of the text is defined by the \override TextSpanner command. For more details see Text spanners.

It also shows how ottava brackets are created.

If the default values of outside-staff-priority do not give you the placing you want, the priority of any of the objects may be overridden. Suppose we would like the ottava bracket to be placed below the text spanner in the example above. All we need to do is to look up the priority of OttavaBracket in the IR or in the table above, and reduce it to a value lower than that of a TextSpanner, remembering that OttavaBracket is created in the Staff context:

% Set details for later Text Spanner
\override TextSpanner.bound-details.left.text
    = \markup { \small \bold Slower }
% Place dynamics above staff
\dynamicUp
% Place following Ottava Bracket below Text Spanners
\once \override Staff.OttavaBracket.outside-staff-priority = #340
% Start Ottava Bracket
\ottava #1
c''4 \startTextSpan
% Add Dynamic Text
c''4\pp
% Add Dynamic Line Spanner
c''4\<
% Add Text Script
c''4^Text |
c''4 c''
% Add Dynamic Text
c''4\ff c'' \stopTextSpan |
% Stop Ottava Bracket
\ottava #0
c'4 c' c' c' |

Note that some of these objects, in particular bar numbers, metronome marks and rehearsal marks, live by default in the Score context, so be sure to use the correct context when these are being overriden.

Slurs by default are classed as within-staff objects, but they often appear above the staff if the notes to which they are attached are high on the staff. This can push outside-staff objects such as articulations too high, as the slur will be placed first. The avoid-slur property of the articulation can be set to 'inside to bring the articulation inside the slur, but the avoid-slur property is effective only if the outside-staff-priority is also set to #f. Alternatively, the outside-staff-priority of the slur can be set to a numerical value to cause it to be placed along with other outside-staff objects according to that value. Here’s an example showing the effect of the two methods:

\relative c'' {
  c4( c^\markup { \tiny \sharp } d4.) c8 |
  c4(
    \once \override TextScript.avoid-slur = #'inside
    \once \override TextScript.outside-staff-priority = ##f
    c4^\markup { \tiny \sharp } d4.) c8 |
  \once \override Slur.outside-staff-priority = #500
    c4( c^\markup { \tiny \sharp } d4.) c8 |
}

Changing the outside-staff-priority can also be used to control the vertical placement of individual objects, although the results may not always be desirable. Suppose we would like “Text3” to be placed above “Text4” in the example under Automatic behavior, above (see Automatic behavior). All we need to do is to look up the priority of TextScript in the IR or in the tables above, and increase the priority of “Text3” to a higher value:

c''2^"Text1"
c''2^"Text2" |
\once \override TextScript.outside-staff-priority = #500
c''2^"Text3"
c''2^"Text4" |

This certainly lifts “Text3” above “Text4” but it also lifts it above “Text2”, and “Text4” now drops down. Perhaps this is not so good. What we would really like to do is to position all the annotation at the same distance above the staff. To do this, we clearly will need to space the notes out horizontally to make more room for the text. This is done using the textLengthOn command.

The \textLengthOn command

By default, text produced by markup takes up no horizontal space as far as laying out the music is concerned. The \textLengthOn command reverses this behavior, causing the notes to be spaced out as far as is necessary to accommodate the text:

\textLengthOn  % Cause notes to space out to accommodate text
c''2^"Text1"
c''2^"Text2" |
c''2^"Text3"
c''2^"Text4" |

The command to revert to the default behavior is \textLengthOff. Alternatively, \once may be used with \textLengthOn if the effect is to be limited to just a single musical moment. The corresponding spacing behavior for rehearsal marks and tempo indications is independently controlled with the commands \markLengthOn and \markLengthOff.

Markup text will also avoid notes which project above the staff. If this is not desired, the automatic displacement upwards may be turned off by setting the priority to #f. Here’s an example to show how markup text interacts with such notes.

\relative {
  % This markup is short enough to fit without collision
  c''2^"Tex" c'' |
  R1 |

  % This is too long to fit, so it is displaced upwards
  c,,2^"Text" c'' |
  R1 |

  % Turn off collision avoidance
  \once \override TextScript.outside-staff-priority = ##f
  c,,2^"Long Text   " c'' |
  R1 |

  % Turn off collision avoidance
  \once \override TextScript.outside-staff-priority = ##f
  \textLengthOn        % and turn on textLengthOn
  c,,2^"Long Text   "  % Spaces at end are honored
  c''2 |
}

Dynamics placement

Dynamic markings will normally be positioned beneath the staff, but may be positioned above with the \dynamicUp command. They will be positioned vertically relative to the note to which they are attached, and will float below (or above) all within-staff objects such as phrasing slurs and bar numbers. This can give quite acceptable results, as this example shows:

\relative {
  \clef "bass"
  \key aes \major
  \time 9/8
  \dynamicUp
  bes4.~\f\< \( bes4 bes8 des4\ff\> c16 bes\! |
  ees,2.~\)\mf ees4 r8 |
}

However, if the notes and attached dynamics are close together the automatic placement will avoid collisions by displacing later dynamic markings further away, but this may not be the optimum placement, as this rather artificial example shows:

\dynamicUp
\relative { a'4\f b\mf a\mp b\p }

Should a similar situation arise in ‘real’ music, it may be preferable to space out the notes a little further, so the dynamic markings can all fit at the same vertical distance from the staff. We were able to do this for markup text by using the \textLengthOn command, but there is no equivalent command for dynamic marks. So we shall have to work out how to do this using \override commands.

Grob sizing

First we must learn how grobs are sized. All grobs have a reference point defined within them which is used to position them relative to their parent object. This point in the grob is then positioned at a horizontal distance, X-offset, and at a vertical distance, Y-offset, from its parent. The horizontal extent of the object is given by a pair of numbers, X-extent, which say where the left and right edges are relative to the reference point. The vertical extent is similarly defined by a pair of numbers, Y-extent. These are properties of all grobs which support the grob-interface.

By default, outside-staff objects are given a width of zero so that they may overlap in the horizontal direction. This is done by the trick of making the leftmost extent infinity and the rightmost extent minus infinity by setting the extra-spacing-width to '(+inf.0 . -inf.0). To ensure they do not overlap in the horizontal direction we must override this value of extra-spacing-width to give them a little extra spacing. The units are the space between two staff lines, so moving the left edge half a unit to the left and the right edge half a unit to the right should do it:

\override DynamicText.extra-spacing-width = #'(-0.5 . 0.5)

Let’s see if this works in our previous example:

\dynamicUp
% Extend width by 1 staff space
\override DynamicText.extra-spacing-width = #'(-0.5 . 0.5)
\relative { a'4\f b\mf a\mp b\p }

This looks better, but maybe we would prefer the dynamic marks to be aligned along the same baseline rather than going up and down with the notes. The property to do this is staff-padding which is covered in the section on collisions (see Collisions of objects).

4.5 Vertical spacing

As a rule, LilyPond’s vertical spacing of musical objects is pretty good. Let’s see how it does with a simple song, with 2 voices and piano accompaniment:

There’s nothing wrong with the default vertical spacing. However, let’s assume that you’re working with a publisher with some specific requirements for vertical spacing of staves and lyrics: they want the lyrics spaced away from any notes, they want the piano accompaniment spaced away from the vocal line and they want the two piano staves pushed together tightly. Let’s start with the lyrics.

Lyrics sit within a system, and therefore the commands to space them are found in Flexible vertical spacing within systems. It tells us that lyrics are non-staff lines and therefore the command to change their spacing will refer to the nonstaff property. Spacing them away from the staff to which they relate (the top line) will use the relatedstaff property. Spacing them from the lower line will use the unrelatedstaff property. The vocal parts are part of a VerticalAxisGroup, so we need to adjust its properties. Let’s try it and see if it works.

<<
  \new ChoirStaff
  <<
    \new Staff {
      \new Voice = "music" {
        b'2 c' c' c'
      }
    }
    \new Lyrics \with {
      \override VerticalAxisGroup.
        nonstaff-relatedstaff-spacing.padding = #5
      \override VerticalAxisGroup.
        nonstaff-unrelatedstaff-spacing.padding = #5
    }
    \lyricsto "music" {
      Here are some lyrics
    }
    \new Staff {
      \clef bass e'2 f e c
    }
  >>
  \new PianoStaff
  <<
    \new Staff {
      g''2 c'' c'' a''
    }
    \new Staff {
      \clef bass e2 f c e
    }
  >>
>>

Well - yes it does, but perhaps too well. When we set the padding to 5, LilyPond adds 5 staff spaces to the distance between objects, which is too much for us here. We’ll use 2.

Next, let’s move the piano music away from the vocal parts. The vocal music is a ChoirStaff, so we need to increase the spacing between that group of staves and the piano staff below. We’ll do this by changing the basic-distance of the StaffGrouper’s staffgroup-staff-spacing.

<<
  \new ChoirStaff \with {
    \override StaffGrouper.
      staffgroup-staff-spacing.basic-distance = #15
  }
  <<
    \new Staff {
      \new Voice = "music" {
        b'2 c' c' c'
      }
    }
    \new Lyrics \with {
      \override VerticalAxisGroup.
        nonstaff-relatedstaff-spacing.padding = #2
      \override VerticalAxisGroup.
        nonstaff-unrelatedstaff-spacing.padding = #2
    }
    \lyricsto "music" {
      Here are some lyrics
    }
    \new Staff {
      \clef bass e'2 f e c
    }
  >>
  \new PianoStaff
  <<
    \new Staff {
      g''2 c'' c'' a''
    }
    \new Staff {
      \clef bass e2 f c e
    }
  >>
>>

Excellent. Now just for the last requirement to make the piano staves closer together. To do this, we again alter the properties of the StaffGrouper, but this time we’re going to reduce both the basic-distance and the padding. We can do this as shown below.

<<
  \new ChoirStaff \with {
    \override StaffGrouper.
      staffgroup-staff-spacing.basic-distance = #15
  }
  <<
    \new Staff {
      \new Voice = "music" {
        b'2 c' c' c'
      }
    }
    \new Lyrics \with {
      \override VerticalAxisGroup.
        nonstaff-relatedstaff-spacing.padding = #2
      \override VerticalAxisGroup.
        nonstaff-unrelatedstaff-spacing.padding = #2
    }
    \lyricsto "music" {
      Here are some lyrics
    }
    \new Staff {
      \clef bass e'2 f e c
    }
  >>
  \new PianoStaff \with {
    \override StaffGrouper.staff-staff-spacing = #'(
                            (basic-distance . 0)
                            (padding . 0))
  }
  <<
    \new Staff {
      g''2 c'' c'' a''
    }
    \new Staff {
      \clef bass e2 f c e
    }
  >>
>>

That’s put them really close together – but it’s what the publisher wanted. They could be moved further apart by altering the padding or basic-distance if wanted.

There are many ways of altering vertical spacing. A key point to remember is that the spacing between objects in a StaffGroup (like GrandStaff or PianoStaff groups) is controlled by the spacing variables of the StaffGrouper. Spacing from ungrouped staves (like Lyrics and Staff) is controlled by the variables of the VerticalAxisGroup. See the Flexible vertical spacing paper variables and Flexible vertical spacing within systems for more details.

4.6 Collisions of objects

4.6.1 Moving objects

This may come as a surprise, but LilyPond is not perfect. Some notation elements can overlap. This is unfortunate, but in fact rather rare. Usually the need to move objects is for clarity or aesthetic reasons – they would look better with a little more or a little less space around them.

There are three main approaches to resolving overlapping notation. They should be considered in the following order:

1. The direction of one of the overlapping objects may be changed using the predefined commands listed above for within-staff objects (see Within-staff objects). Stems, slurs, beams, ties, dynamics, text and tuplets may be repositioned easily in this way. The limitation is that you have a choice of only two positions, and neither may be suitable.
2. The object properties, which LilyPond uses when positioning layout objects, may be modified using \override. The advantages of making changes to this type of property are (a) that some other objects will be moved automatically if necessary to make room and (b) the single override can apply to all instances of the same type of object. Such properties include:
   • direction

     This has already been covered in some detail – see Within-staff objects.

   • padding, right-padding, staff-padding

     As an object is being positioned the value of its padding property specifies the gap that must be left between itself and the nearest edge of the object against which it is being positioned. Note that it is the padding value of the object being placed that is used; the padding value of the object which is already placed is ignored. Gaps specified by padding can be applied to all objects which support the side-position-interface.

     Instead of padding, the placement of groups of accidentals is controlled by right-padding. This property is to be found in the AccidentalPlacement object which, note, lives in the Staff context. In the typesetting process the note heads are typeset first and then the accidentals, if any, are added to the left of the note heads using the right-padding property to determine the separation from the note heads and between individual accidentals. So only the right-padding property of the AccidentalPlacement object has any effect on the placement of the accidentals.

     The staff-padding property is closely related to the padding property: padding controls the minimum amount of space between any object which supports the side-position-interface and the nearest other object (generally the note or the staff lines); staff-padding applies only to those objects which are always set outside the staff – it controls the minimum distance from the staff to the outside-staff object. Note that staff-padding has no effect on objects that are positioned relative to the note rather than the staff, even though it may be overridden without error for such objects – it is simply ignored.

     To discover which padding property is required for the object you wish to reposition, you need to return to the IR and look up the object’s properties. Be aware that the padding properties might not be located in the obvious object, so look in objects that appear to be related.

     All padding values are measured in staff spaces. For most objects, this value is set by default to be around 1.0 or less (it varies with each object). It may be overridden if a larger (or smaller) gap is required.

   • self-alignment-X

     This property can be used to align the object to the left, to the right, or to center it with respect to the parent object’s reference point. It may be used with all objects which support the self-alignment-interface. In general these are objects that contain text. The values are LEFT, RIGHT or CENTER. Alternatively, a numerical value between -1 and +1 may be specified, where -1 is left-aligned, +1 is right-aligned, and numbers in between move the text progressively from left-aligned to right-aligned. Numerical values greater than 1 may be specified to move the text even further to the left, or less than -1 to move the text even further to the right. A change of 1 in the value corresponds to a movement of half the text’s length.

   • extra-spacing-width

     This property is available for all objects which support the item-interface. It takes two numbers, the first is added to the leftmost extent and the second is added to the rightmost extent. Negative numbers move the edge to the left, positive to the right, so to widen an object the first number must be negative, the second positive. Note that not all objects honor both numbers. For example, the Accidental object only takes notice of the first (left edge) number.

   • staff-position

     staff-position is a property of the staff-symbol-referencer-interface, which is supported by objects which are positioned relative to the staff. It specifies the vertical position of the object relative to the center line of the staff in half staff-spaces. It is useful in resolving collisions between layout objects like multi-measure rests, ties and notes in different voices.

   • horizontal-shift

     Within a voice, all the notes occuring at the same musical moment are grouped into a note column, and a NoteColumn object is created to control the horizontal positioning of that group of notes (see “Note columns” in Explicitly instantiating voices). If and only if two or more note columns within a single Staff context, both with stems in the same direction, occur at the same musical moment, the values of their horizontal-shift properties are used to rank them and the columns in the higher ranks are progessively offset to avoid collisions of the noteheads. This property is set by the \voiceXXX commands and may be overridden directly with an \override command or, more usually, by the \shiftOn commands. Note that this property is used to rank the note columns for off-setting - it does not specify the magnitude of the offset, which is progressively increased in steps based on the note head’s width for each rank. The steps are usually of half a note head’s width, but may be a full note head’s width when a closely spaced group of notes is involved.

   • force-hshift

     The force-hshift property is a property of a NoteColumn (actually of the note-column-interface). Changing it permits a note column to be moved in situations where the note columns overlap. Note that it has no effect on note columns that do not overlap. It is specified in units appropriate to a note column, viz. the note head width of the first voice note. It should be used in complex situations where the normal \shiftOn commands (see Explicitly instantiating voices) do not resolve the note conflict satisfactorily. It is preferable to the extra-offset property for this purpose as there is no need to work out the distance in staff-spaces, and moving the notes into or out of a NoteColumn affects other actions such as merging note heads.

3. Finally, when all else fails, objects may be manually repositioned relative to the staff center line vertically, or by displacing them by any distance to a new position. The disadvantages are that the correct values for the repositioning have to be worked out, often by trial and error, for every object individually, and, because the movement is done after LilyPond has placed all other objects, the user is responsible for avoiding any collisions that might ensue. But the main difficulty with this approach is that the repositioning values may need to be reworked if the music is later modified. The properties that can be used for this type of manual repositioning are:

   extra-offset

   This property applies to any layout object supporting the grob-interface. It takes a pair of numbers which specify the extra displacement in the horizontal and vertical directions. Negative numbers move the object to the left or down. The units are staff-spaces. The extra displacement is made after the typesetting of objects is finished, so an object may be repositioned anywhere without affecting anything else.

   positions

   This is most useful for manually adjusting the slope and height of beams, slurs, and tuplets. It takes a pair of numbers giving the position of the left and right ends of the beam, slur, etc. relative to the center line of the staff. Units are staff-spaces. Note, though, that slurs and phrasing slurs cannot be repositioned by arbitrarily large amounts. LilyPond first generates a list of possible positions for the slur and by default finds the slur that “looks best”. If the positions property has been overridden the slur that is closest to the requested positions is selected from the list.