Update from Carl.

[lilypond.git] / Documentation / user / chords.itely

@c -*- coding: utf-8; mode: texinfo; -*-
@ignore
    Translation of GIT committish: FILL-IN-HEAD-COMMITTISH

    When revising a translation, copy the HEAD committish of the
    version that you are working on.  See TRANSLATION for details.
@end ignore

@c \version "2.11.38"


@node Chord notation
@section Chord notation

Chords can be entered in chord mode, which recognizes some
traditional European chord naming conventions.  Chord names can also
be displayed.  In addition, figured bass notation can be displayed.

@menu
* Chord mode::                  
* Displaying chords::           
* Figured bass::                
@end menu


@node Chord mode
@subsection Chord mode

@cindex chord chords

Chord mode is used to enter chords using an indicator of the chord
structure, rather than the chord pitches.

@menu
* Chord mode overview::         
* Common chords::               
* Extended and altered chords::  
@end menu

@node Chord mode overview
@unnumberedsubsubsec Chord mode overview

@cindex chord names
@cindex chord mode

Chords can be entered as simultaneous music, as discussed in
@ref{Chorded notes}.

Chords can also be entered in @qq{chord mode}, which is an input
mode that focuses on the structures of chords in traditional
European music, rather than on specific pitches.  This is
convenient for those who are familiar with using chord names to
describe chords.  More information on different input modes can be
found at @ref{Input modes}.

@lilypond[verbatim,quote,ragged-right,relative=1]
\chordmode { c1 g a g c }
@end lilypond

Chords entered using chord mode are music elements, and can be
transposed just like chords entered using simultaneous music.

Chord mode and note mode can be mixed in sequential music:
@lilypond[verbatim,quote,ragged-right,relative=1]
{ <c e g>2 < g b d >
  \chordmode { c2 f}
  < c e g > < g' b d >
  \chordmode { f g}
}
@end lilypond


@seealso

Music Glossary:
@rglos{chord}.

Notation Reference:
@ref{Chorded notes},
@ref{Input modes}.

Snippets:
@rlsr{Chords}

@knownissues

When chord mode and note mode are mixed in sequential music, and
chord mode comes first, the note mode will create a new @code{Staff}
context.

@lilypond[verbatim,quote,ragged-right,relative=1]
{
  \chordmode { c2 f}
  < c e g > < g' b d >
}
@end lilypond

To avoid this behavior, explicitly create the @code{Staff} context:

@lilypond[verbatim,quote,ragged-right,relative=1]
\new Staff {
  \chordmode { c2 f}
  < c e g > < g' b d >
}
@end lilypond

@node Common chords
@unnumberedsubsubsec Common chords

@cindex triads
@cindex seventh chords
@cindex root of chord
@cindex modifiers, in chords.
@cindex chord quality

Major triads are entered by including the root and an
optional duration:

@lilypond[verbatim,quote,relative=1,ragged-right]
\chordmode { c2 f4 g }
@end lilypond

Minor, augmented, and diminished triads are entered by placing
@code{:} and a quality modifier string after the duration:

@lilypond[verbatim,quote,ragged-right,relative=1]
\chordmode { c2:m f4:aug g:dim }
@end lilypond

Seventh chords may be created:

@lilypond[quote,ragged-right,fragment,verbatim,relative=1]
\chordmode { c1:7 c:m7 c:maj7 c:dim7 c:aug7 }
@end lilypond

@funindex aug
@funindex dim
@funindex maj
@funindex m

The table belows shows the actions of the quality modifiers on
triads and seventh chords.

@table @code

@item m
The minor chord.  This modifier lowers the 3rd and (if present) the
7th step.

@item dim
The diminished chord.  This modifier lowers the 3rd, 5th and (if
present) the 7th step.

@item aug
The augmented chord.  This modifier raises the 5th step.

@item maj
The major 7th chord.  This modifier adds a raised 7th step.  The
@code{7} following @code{maj} is optional.  Do NOT use this modifier
to create a major triad.

@end table

@c TODO -- perhaps add warning about c and c:maj being different, while
@c   c:maj and c:maj7 are the same

@seealso

Snippets:
@rlsr{Chords}

@node Extended and altered chords
@unnumberedsubsubsec Extended and altered chords

@cindex extended chords
@cindex altered chords

Chord structures of arbitrary complexity can be created in chord
mode.  The modifier string can be used to extend a chord, add or
remove chord steps, raise or lower chord steps, and add a bass note
or create an inversion.

The first number following the @code{:} is taken to be the extent
of the chord.  The chord is constructed by sequentially adding
thirds to the root until the specified number has been reached.
If the extent is not a third (e.g., 6), thirds are added up to the
highest third below the extent, and then the step of the extent is
added.  The largest possible value for the extent is 13.  Any
larger value is interpreted as 13.

@lilypond[quote,ragged-right,fragment,verbatim,relative=1]
\chordmode {
  c:2 c:3 c:4 c:5
  c:6 c:7 c:8 c:9
  c:10 c:11 c:12 c:13
}
@end lilypond

Since an unaltered 11 does not sound good when combined with an
unaltered 13, the 11 is removed from a @code{:13} chord (unless it
is added explicitly).

@lilypond[quote,ragged-right,fragment,verbatim,relative=1]
\chordmode { c1:13 c:13.11 c:m13 }
@end lilypond

@cindex additions, in chords

Individual steps can be added to a chord.  Additions follow the
extent and are prefixed by a dot (@code{.}).

@lilypond[quote,verbatim,fragment,relative=1]
\chordmode { c1:5.6 c:3.7.8 c:3.6.13 }
@end lilypond

Added steps can be as high as desired.

@lilypond[quote,verbatim,fragment,relative=1]
\chordmode { c4:5.15 c:5.20 c:5.25 c:5.30 }
@end lilypond

@cindex chord steps, altering

Added chord steps can be altered by suffixing a @code{-} or @code{+}
sign to the number.  To alter a step that is automatically included
as part of the basic chode structure, add it as an altered step.

@lilypond[quote,verbatim,fragment,relative=1]
\chordmode { c1:7+ c:5+.3- c:3-.5-.7- }
@end lilypond

@cindex removals, in chords

@funindex ^

A step to be removed from the chord  must come at the end of a
modifier string and be prefixed by @code{^}.  Only one removal with @code{^}
is allowed in a modifier string.

@lilypond[quote,verbatim,fragment,relative=1]
\chordmode { c1^3 c:7^5 c:9^3.5 }
@end lilypond

@funindex sus

The modifier @code{sus} can be added to the modifier string to
create suspended chords.  This removes the 3rd step from the chord.
Append either @code{2} or @code{4} to add the 2nd or 4th step to the
chord.  @code{sus} is equivalent to @code{^3}; @code{sus4} is
equivalent to @code{.4^3}.

@lilypond[quote,ragged-right,fragment,verbatim]
\chordmode { c1:sus c:sus2 c:sus4 c:5.4^3 }
@end lilypond

It is possible to remove the 3rd step with @code{sus} and remove
another step with @code{^} in one modifier string.

@funindex /
@cindex chord inversions
@cindex bass note, for chords

Inversions (putting a pitch other than the root on the bottom of the
chord) and added bass notes can be specified by appending
@code{/}@var{pitch} to the chord.

@lilypond[quote,ragged-right,fragment,verbatim, relative=2]
\chordmode { c1 c/g c/f }
@end lilypond

@funindex /+

A bass note that is part of the chord can be added, instead of
moved as part of an inversion, by using @code{/+}@var{pitch}.

@lilypond[quote,ragged-right,fragment,verbatim]
\chordmode { c1 c/+g c/+f }
@end lilypond

@seealso

Snippets:
@rlsr{Chords}

@knownissues

Each step can only be present in a chord once.  The following
simply produces the augmented chord, since @code{5+} is
interpreted last.

@lilypond[quote,ragged-right,verbatim,fragment]
\chordmode { c1:5.5-.5+ }
@end lilypond

Only one step can be removed from a chord.  If a chord with multiple
removed steps is desired, it must be built through addition of
multiple steps.


@node Displaying chords
@subsection Displaying chords

Chords can be displayed by name, in addition to the standard display
as notes on a staff.

@menu
* Printing chord names::        
* Customizing chord names::     
@end menu

@node Printing chord names
@unnumberedsubsubsec Printing chord names

@cindex printing chord names
@cindex chord names
@cindex chords

Chord names are printed in the @code{ChordNames} context:

@lilypond[verbatim,quote,relative=1,ragged-right]
\new ChordNames {
  \chordmode { c2 f4. g8 }
}
@end lilypond

Both chord names and the notes can be displayed:

@lilypond[verbatim,quote,ragged-right]
myChords = \relative c'{
  \chordmode { c2 f4. g8 }
}
<<
  \new ChordNames {
    \chordmode { c2 f4. g8 }
  }
  {
    \chordmode { c2 f4. g8 }
  }
>>
@end lilypond

Setting @rinternals{ChordNames}.@code{chordChanges} to true causes
chords names to be displayed only when the chord changes or at
the start of a new line

@lilypond[quote,verbatim,ragged-right]
harmonies = \chordmode {
  c1:m c:m \break c:m c:m d
}
<<
  \new ChordNames {
    \set chordChanges = ##t
    \harmonies
  }
  \new Staff {
    \relative c' { \harmonies }
  }
>>
@end lilypond

Chords can be entered as simultaneous notes or through the use of
chord mode.  The displayed chord name will be the same, regardless
of the mode of entry, unless there are inversions or added bass notes:

@lilypond[quote,ragged-right,verbatim]
<<
  \new ChordNames {
    <c e g>2  <f bes c>
    <f c' e g>1
    \chordmode {
      c2 f:sus4 c1:/f
    }
  }
  {
    <c e g>2  <f bes c>
    <f, c' e g>1
    \chordmode {
      c2 f:sus4 c1:/f
    }
  }
>>
@end lilypond

@funindex{\chords}

@code{\chords} is a shortcut method used to change the input mode to
@code{\chordmode} and create a @code{ChordNames} context, with the
following result:

@lilypond[verbatim,quote,ragged-right, relative=1]
\chords { c2 f4.:m g8:maj7 }
@end lilypond

@cindex lead sheet

When put together, chord names, a melody, and lyrics form a lead
sheet:

@lilypond[verbatim,quote,ragged-right]
<<
  \chords { c2 g:sus4 f e }
  \relative c'' {
    a4 e c8 e r4
    b2 c4( d)
  }
  \addlyrics { One day this shall be free __ }
>>
@end lilypond

@snippets

@c TODO -- replace this with a snippets
To add bar indications in the @code{ChordNames}
context, add @rinternals{Bar_engraver}.

@lilypond[ragged-right,verbatim]
\new ChordNames \with {
  \override BarLine #'bar-size = #4
  \consists "Bar_engraver"
}
\chordmode {
  f1:maj7 f:7 bes:7 c:maj7 ees e
}
@end lilypond

@seealso

Music Glossary:
@rglos{chord}.


Notation Reference:
@ref{Writing music in parallel}.


Snippets:
@rlsr{Chords}.

Internals Reference:
@rinternals{ChordNames},
@rinternals{Volta_engraver},
@rinternals{Bar_engraver}.

@knownissues

Chords containing inversions or altered bass notes are not named
properly if entered using simultaneous music.


@node Customizing chord names
@unnumberedsubsubsec Customizing chord names

@cindex customizing chord names

There is no unique system for naming chords.  Different musical
traditions use different names for the same set of chords.  There
are also different symbols displayed for a given chord name.   The
names and symbols displayed for chord names are customizable.

@cindex Banter
@cindex jazz chords
@cindex chords, jazz

The default chord name layout is a system for Jazz music, proposed
by Klaus Ignatzek (see @ref{Literature list}).  There are also two
other chord name schemes implemented: an alternate Jazz chord
notation, and a systematic scheme called Banter chords.  The
alternate Jazz notation is also shown on the chart in @ref{Chord
name chart}.

In addition to the different naming systems, different note names
are used for the root in different languages.  The predefined
variables @code{\germanChords}, @code{\semiGermanChords},
@code{\italianChords} and @code{\frenchChords} set these variables.
The effect is demonstrated here:

@lilypondfile[ragged-right]{chord-names-languages.ly}

If none of the default settings give the desired output, the chord
name display can be tuned through the following properties.

@table @code

@funindex chordRootNamer

@item chordRootNamer

The chord name is usually printed as a letter for the root with an
optional alteration.  The transformation from pitch to letter is
done by this function.  Special note names (for example, the German
@q{H} for a B-chord) can be produced by storing a new function in
this property.

@funindex majorSevenSymbol

@item majorSevenSymbol

This property contains the markup object used to follow the output
of @code{chordRootNamer} to dentify a major 7 chord. Predefined
options are @code{whiteTriangleMarkup} and
@code{blackTriangleMarkup}.

@funindex chordNoteNamer

@item chordNoteNamer

When the chord name contains additional pitches other than the root
(e.g., an added bass note), this function is used to print the
additional pitch.  By default the pitch is printed using
@code{chordRootNamer}. The @code{chordNoteNamer} property can be set
to a specialized function to change this behavior.  For example, the
bass note can be printed in lower case.

@funindex chordNameSeparator

@item chordNameSeparator

Different parts of a chord name are normally separated by a slash.
By setting @code{chordNameSeparator}, you can use any desired markup
for a separator, e.g.,

@lilypond[quote,ragged-right,fragment,verbatim]
\chords {
  c:7sus4
  \set chordNameSeparator
    = \markup { \typewriter "|" }
  c:7sus4
}
@end lilypond

@funindex chordNameExceptions

@item chordNameExceptions

This property is a list of pairs.  The first item in each pair
is a set of pitches used to identify the steps present in the chord.
The second item is a markups that will follow the @code{chordRootNamer}
output to create the chord name.  See @code{FIXME -- future ref to snippet}
for information on creating this list.

@funindex chordPrefixSpacer
@item chordPrefixSpacer

The @q{m} for minor chords is usually printed immediately to the
right of the root of the chord.  By setting
@code{chordPrefixSpacer}, you can fix a spacer between the root
and @q{m}.  The spacer is not used when the root is altered.

@end table

@predefined

@funindex major seven symbols
@code{\whiteTriangleMarkup}
@code{\blackTriangleMarkup}
@funindex \germanChords
@code{\germanChords},
@funindex \semiGermanChords
@code{\semiGermanChords},
@funindex \italianChords
@code{\italianChords},
@funindex \frenchChords
@code{\frenchChords}.


@snippets
@lilypondfile[verbatim,lilyquote,texidoc,doctitle]
{chord-names-jazz.ly}

@lilypondfile[verbatim,lilyquote,texidoc,doctitle]
{chord-name-exceptions.ly}
@cindex exceptions, chord names.

@lilypondfile[verbatim,lilyquote,texidoc,doctitle]
{chord-name-major7.ly}

@c  This has yet to be approved
@ignore
@lilypondfile[verbatim,lilyquote,texidoc,doctitle]
{adding-bars-to-chordnames.ly)
@end ignore

@c This has yet to be made a docs snippet
@ignore
@lilypondfile[verbatim,lilyquote,texidoc,doctitle]
(volta-brackets-over-chord-names.ly)
@end ignore


@seealso

Installed Files:
@file{scm/@/chords@/-ignatzek@/.scm},
@file{scm/@/chord@/-entry@/.scm},
@file{ly/@/chord@/-modifier@/-init@/.ly}.

Snippets:
@rlsr{Chords}.

Internals Reference:
@c @rinternals{}.

@knownissues

Chord names are determined from both the pitches that are present
in the chord and the information on the chord structure that may
have been entered in @code{\chordmode}.  If the simultaneous pitches
method of entering chords is used, undesired names result from
inversions or bass notes.

@lilypond[quote,ragged-right,verbatim]
myChords = \relative c' {
  \chordmode{ c1 c/g c/f }
  <c e g> <g c e> <f c' e g>
}
<<
  \new ChordNames { \myChords }
  \new Staff { \myChords }
>>
@end lilypond


@node Figured bass
@subsection Figured bass

@menu
* Introduction to figured bass::  
* Entering figured bass::       
* Displaying figured bass::     
@end menu

@node Introduction to figured bass
@subsubsection Introduction to figured bass

@cindex Basso continuo

@c TODO: musicological blurb about FB

LilyPond has support for figured bass

@lilypond[quote,ragged-right,verbatim,fragment]
<<
  \new Voice { \clef bass dis4 c d ais g fis}
  \new FiguredBass \figuremode {
    < 6 >4 < 7\+ >8 < 6+ [_!] >
    < 6 >4 <6 5 [3+] >
    < _ >4 < 6 5/>4
  }
>>
@end lilypond

The support for figured bass consists of two parts: there is an
input mode, introduced by @code{\figuremode}, where you can enter
bass figures as numbers, and there is a context named
@rinternals{FiguredBass} that takes care of making
@rinternals{BassFigure} objects.

Although the support for figured bass may superficially resemble chord
support, it is much simpler.  The @code{\figuremode} mode simply
stores the numbers and @rinternals{FiguredBass} context prints them
as entered.  There is no conversion to pitches and no realizations of
the bass are played in the MIDI file.

Internally, the code produces markup texts.  You can use any of the
markup text properties to override formatting.  For example, the
vertical spacing of the figures may be set with @code{baseline-skip}.


@menu
* Entering figured bass::
* Displaying figured bass::
@end menu

@node Entering figured bass
@unnumberedsubsubsec Entering figured bass


In figures input mode, a group of bass figures is delimited by
@code{<} and @code{>}.  The duration is entered after the @code{>}
@example
<4 6>2
@end example
@lilypond[quote,ragged-right,fragment]
\new FiguredBass
\figuremode { <4 6>2 }
@end lilypond

Accidentals are added when you append @code{-}, @code{!}, and @code{+}
to the numbers.  A plus sign is added when you append @code{\+}, and
diminished fifths and sevenths can be obtained with @code{5/} and @code{7/}.

@example
<4- 6+ 7!>3 <5++> <3--> <7/> r <6\+ 5/>
@end example
@lilypond[quote,ragged-right,fragment]
\figures { <4- 6+ 7!>4 <5++> <3--> <7/> r <6\+ 5/> }
@end lilypond

Spaces may be inserted by using @code{_}.  Brackets are
introduced with @code{[} and @code{]}.  You can also include text
strings and text markups, see @ref{Text markup commands}.

@example
< [4 6] 8 [_! 12] >4 < 5 \markup @{ \number 6 \super (1) @} >
@end example
@lilypond[quote,ragged-right,fragment]
\new FiguredBass
\figuremode { < [4 6] 8 [_! 12] >4 < 5 \markup{ \tiny \number 6 \super (1)} > }
@end lilypond


It is also possible to use continuation lines for repeated figures,

@lilypond[verbatim,relative=1]
<<
  \new Staff {
    \clef bass
    c4 c c
  }
  \figures {
    \set useBassFigureExtenders = ##t
    <4 6>4 <3 6> <3 7>
  }
>>
@end lilypond

@noindent
In this case, the extender lines always replace existing figures.

The @code{FiguredBass} context doesn't pay attention to the actual
bass line.  As a consequence, you may have to insert extra figures to
get extender lines below all notes, and you may have to add @code{\!}
to avoid getting an extender line, e.g.

@lilypond[relative=1]
<<
  \new Voice
  \figures {
    \set useBassFigureExtenders = ##t
    <6 4->4. <6 4->16. <6 4->32 <5>8. r16 <6>8 <6\! 5->
  }
  {
    \clef bass
    f16. g32 f16. g32 f16. g32 f16. g32 f8. es16 d8 es
  }
>>
@end lilypond

When using continuation lines, common figures are always put in the
same vertical position.  When this is unwanted, you can insert a rest
with @code{r}.  The rest will clear any previous alignment.  For
example, you can write

@example
<4 6>8 r8
@end example

@noindent
instead of
@example
<4 6>4
@end example

Accidentals and plus signs can appear before or after the numbers,
depending on the @code{figuredBassAlterationDirection} and
@code{figuredBassPlusDirection}
properties

@lilypond
  \figures {
    <6\+> <5+> <6 4-> r
    \set figuredBassAlterationDirection = #1
    <6\+> <5+> <6 4-> r
    \set figuredBassPlusDirection = #1
    <6\+> <5+> <6 4-> r
    \set figuredBassAlterationDirection = #-1
    <6\+> <5+> <6 4-> r
  }
@end lilypond


Figured bass can also be added to @code{Staff} contexts
directly.  In this case, their vertical position is adjusted
automatically.

@lilypond[ragged-right,fragment,quote]
<<
  \new Staff = someUniqueName
  \relative c'' {
    c4 c'8 r8 c,4 c'
  }

  %% send to existing Staff.
  \context Staff = someUniqueName
  \figuremode {
    <4>4 <6 10>8 s8

    \set Staff.useBassFigureExtenders = ##t
    <4 6>4 <4 6>
  }
>>
@end lilypond

@c @predefined

@c @snippets

@seealso
@c Music Glossary:
@c @rglos{}.

@c Learning Manual:
@c @rlearning{}.

@c Notation Reference:
@c @ruser{}.

@c Application Usage:
@c @rprogram{}.

@c Installed Files:
@c @file{}.

@c Snippets:
@c @rlsr{}.

@c Internals Reference:
@c @rinternals{}.

@c @knownissues

@node Displaying figured bass
@unnumberedsubsubsec Displaying figured bass

Figured bass is displayed using the @code{FiguredBass} context.

@c @predefined

@c @snippets

@seealso
@c Music Glossary:
@c @rglos{}.

@c Learning Manual:
@c @rlearning{}.

@c Notation Reference:
@c @ruser{}.

@c Application Usage:
@c @rprogram{}.

@c Installed Files:
@c @file{}.

@c Snippets:
@c @rlsr{}.

Internals Reference:
@rinternals{NewBassFigure},
@rinternals{BassFigureAlignment},
@rinternals{BassFigureLine},
@rinternals{BassFigureBracket},
@rinternals{BassFigureContinuation},
@rinternals{FiguredBass}.

@knownissues

By default, this method produces figures above the notes.  To get
figures below the notes, use

@example
\override Staff.BassFigureAlignmentPositioning #'direction = #DOWN
@end example

When using figured bass above the staff with extender lines and
@code{implicitBassFigures} the lines may become swapped around.
Maintaining order consistently will be impossible when multiple figures
have overlapping extender lines.  To avoid this problem, please
use @code{stacking-dir} on @code{BassFigureAlignment}.


@seealso