version that you are working on. See TRANSLATION for details.
@end ignore
-@c \version "2.11.51"
+@c \version "2.11.61"
@node Simultaneous notes
@menu
* Chorded notes::
+* Simultaneous expressions::
* Clusters::
@end menu
@cindex chords
@cindex brackets, angle
+@cindex angle brackets
@cindex relative pitch in chords
+
@funindex <
@funindex >
@funindex <...>
-A chord is formed by a enclosing a set of pitches between @code{<} and
-@code{>}. A chord may be followed by a duration and/or a set of
-articulations, just like simple notes:
+A chord is formed by enclosing a set of pitches between @code{<}
+and @code{>}. A chord may be followed by a duration and/or a set
+of articulations, just like simple notes:
@lilypond[verbatim,quote,relative=1]
<c e g>2 <c f a>4-> <e g c>-.
@end lilypond
-Relative mode can be used for pitches in chords; the preceding pitch
-into the same chord is still used as a reference for relative pitches,
-but when a chord is completed, the reference pitch for relative mode
-is the first note of this chord --not the last note of the chord.
+Relative mode can be used for pitches in chords. The octave of each
+pitch is chosen using the preceding pitch as a reference except in
+the case of the first pitch in a chord: the reference for the first
+pitch is the @emph{first} pitch of the preceding chord.
For more information about chords, see @ref{Chord notation}.
Snippets:
@rlsr{Simultaneous notes}.
-@ignore
-@knownissues
+@node Simultaneous expressions
+@unnumberedsubsubsec Simultaneous expressions
-For some reason, music expressions like @code{<< @{ g8 e8 @} a4 >>}
-that should automatically turn into chords, appear split in two
-staves. To avoid this, use explicit chords instead as in
-@code{<g a>8 <e a>8}.
-@end ignore
+One or more music expressions enclosed in double angle brackets are
+taken to be simultaneous. If the first expression begins with a
+single note or if the whole simultaneous expression appears
+explicitly within a single voice, the whole expression is placed on
+a single staff; otherwise the elements of the simultaneous
+expression are placed on separate staves.
+
+The following examples show simultaneous expressions on one staff:
+
+@lilypond[quote,verbatim,relative=2]
+\new Voice { % explicit single voice
+ << {a4 b g2} {d4 g c,2} >>
+}
+@end lilypond
+
+@lilypond[quote,verbatim,relative=2]
+% single first note
+a << {a4 b g} {d4 g c,} >>
+@end lilypond
+
+This can be useful if the simultaneous sections have identical
+rhythms, but attempts to attach notes with different durations
+to the same stem will cause errors.
+
+The following example shows how simultaneous expressions can
+generate multiple staves implicitly:
+
+@lilypond[quote,verbatim,relative=2]
+% no single first note
+<< {a4 b g2} {d4 g2 c,4} >>
+@end lilypond
+
+Here different rhythms cause no problems.
@node Clusters
@cindex cluster
@cindex note cluster
+
@funindex \makeClusters
@funindex makeClusters
-A cluster indicates a continuous range of pitches to be played. They
-can be denoted as the envelope of a set of notes. They are entered by
-applying the function @code{\makeClusters} to a sequence of chords,
-e.g.,
+A cluster indicates a continuous range of pitches to be played.
+They can be denoted as the envelope of a set of notes. They are
+entered by applying the function @code{\makeClusters} to a sequence
+of chords, e.g.,
@lilypond[quote,relative=2,verbatim]
\makeClusters { <g b>2 <c g'> }
they appear too narrow.
Clusters do not have a stem and cannot indicate durations by
-themselves. Separate clusters would need a separating rest between
-them.
+themselves, but the length of the printed cluster is determined by
+the durations of the defining chords. Separate clusters need a
+separating rest between them.
+Clusters do not produce MIDI output.
@node Multiple voices
@subsection Multiple voices
@cindex polyphony, single-staff
@cindex voice
@cindex lyrics assigned to one voice
+
@funindex \voiceOne
@funindex voiceOne
@funindex \voiceOne ... \voiceFour
@funindex \oneVoice
@funindex oneVoice
-The basic structure of code needed to achieve multiple, independent
+@strong{@i{Explicitly instantiating voices}}
+
+The basic structure needed to achieve multiple independent
voices in a single staff is illustrated in the following example:
@lilypond[quote,relative=3,verbatim]
>>
@end lilypond
-Here, voices are instantiated explicitly and are given a name. The
-@code{\voiceOne} ... @code{\voiceFour} commands set up the voices so
-that first and third voices get stems up, second and fourth voices get
-stems down, third and fourth voice note heads are horizontally
-shifted, and rests in the respective voices are automatically moved to
-avoid collisions. Using the @code{\oneVoice} command, all the voice
-settings are put back to the neutral directions typical of a
-single-voice passage.
-
-We can make a voice to be in the same @code{Voice} context before
-and after a temporary polyphonic passage. For example, the following
-construct keeps a voice alive throughout the polyphonic section. Said
-voice is the first one inside of the two-voice section, and the extra
-voice is the second one.
+Here, voices are instantiated explicitly and are given names. The
+@code{\voiceOne} ... @code{\voiceFour} commands set up the voices
+so that first and third voices get stems up, second and fourth
+voices get stems down, third and fourth voice note heads are
+horizontally shifted, and rests in the respective voices are
+automatically moved to avoid collisions. The @code{\oneVoice}
+command returns all the voice settings to the neutral default
+directions.
+
+@strong{@i{Temporary polyphonic passages}}
+
+A temporary polyphonic passage can be created with the following
+construct:
@example
-<< @{ \voiceOne ... @} \new Voice @{ \voiceTwo ... @} >> \oneVoice
+<< @{ \voiceOne ... @}
+ \new Voice @{ \voiceTwo ... @}
+>> \oneVoice
@end example
-Using the name given when created, this allows lyrics to be assigned
-to one consistent voice.
+Here, the first expression within a temporary polyphonic passage is
+placed into the @code{Voice} context which was in use immediately
+before the polyphonic passage, and that same @code{Voice} context
+continues after the temporary section. Other expressions within
+the angle brackets are assigned to distinct temporary voices.
+This allows lyrics to be assigned to one continuing voice before,
+during and after a polyphonic section:
@lilypond[quote, verbatim, relative=2]
<<
}
\new Voice {
\voiceTwo
- e d
+ d2
}
>>
\oneVoice
- e
+ e4
}
\new Lyrics \lyricsto "melody" {
This is my song.
>>
@end lilypond
-Here, the @code{\voiceOne} and @code{\voiceTwo} commands help to make clear what
-settings does each voice receive.
+Here, the @code{\voiceOne} and @code{\voiceTwo} commands are
+required to define the settings of each voice.
+
+@strong{@i{The double backslash construct}}
-The @code{<<@{...@} \\ @{...@}>>} construction, where the two (or
-more) voices are separated by double backslashes, can be used as a
-simplified method to print multiple voices in a single staff. Our
-first example could be typeset as follows:
+The @code{<< @{...@} \\ @{...@} >>} construct, where the two (or
+more) expressions are separated by double backslashes, behaves
+differently to the similar construct without the double backslashes:
+@emph{all} the expressions within this contruct are assigned
+to new @code{Voice} contexts. These new @code{Voice} contexts
+are created implicitly and are given the fixed names @code{"1"},
+@code{"2"}, etc.
+
+The first example could be typeset as follows:
@lilypond[quote,relative=3,verbatim]
<<
>>
@end lilypond
-This syntax is simpler and can be used where it does not matter that
-temporary voices are created and then discarded. These implicitly
-created voices are given the settings equivalent to the effect of the
-@code{\voiceOne} ... @code{\voiceFour} commands, in the order in which
-they appear in the code. In the following example, the intermediate
-voice has stems up, therefore we enter it in the third place, so it
-becomes voice three which has the stems up as desired.
+This syntax can be used where it does not matter that temporary
+voices are created and then discarded. These implicitly created
+voices are given the settings equivalent to the effect of the
+@code{\voiceOne} ... @code{\voiceFour} commands, in the order in
+which they appear in the code.
+
+In the following example, the intermediate voice has stems up,
+therefore we enter it in the third place, so it becomes voice
+three, which has the stems up as desired. Spacer rests are
+used to avoid printing doubled rests.
@lilypond[quote,relative=3,verbatim]
<<
- { r8 g g g g f16 es f8 d }
+ { r8 g g g g f16 ees f8 d }
\\
- { es,8 r es r d r d r }
+ { ees,8 r ees r d r d r }
\\
{ d'8 s c s bes s a s }
>>
@end lilypond
-Spacer rests are often used to avoid too many rests, as seen in the
-example above.
-
-In all but simplest works it is advisable to create explicit
-@code{Voice} contexts using the @code{\new} and @code{\context}
-commands as it is explained in @rlearning{Contexts and engravers} and
+In all but the simplest works it is advisable to create explicit
+@code{Voice} contexts as explained in @rlearning{Contexts and engravers} and
@rlearning{Explicitly instantiating voices}.
+@strong{@i{Identical rhythms}}
+
In the special case that we want to typeset parallel pieces of music
that have the same rhythm, we can combine them into a single
@code{Voice} context, thus forming chords. To achieve this, enclose
-them in a simple simultaneous music construction and make it to be an
-explicit voice:
+them in a simple simultaneous music construct within an explicit voice:
@lilypond[quote,relative=2,verbatim]
\new Voice <<
>>
@end lilypond
-To revert the standard presentation, the @code{\voiceNeutralstyle}
-command is used.
+The @code{\voiceNeutralstyle} command is used to revert to the
+standard presentation.
@predefined
@funindex \mergeDifferentlyHeadedOff
@funindex mergeDifferentlyHeadedOff
-Note heads with equal durations are automatically merged, while
-note heads with unequal durations are not merged. Rests opposite
-a stem are shifted vertically.
+The note heads of notes in different voices with the same pitch,
+same note head and opposite stem direction are automatically
+merged, but notes with different note heads or the same stem
+direction are not. Rests opposite a stem in a different voice
+are shifted vertically.
@lilypond[quote,verbatim,relative=2]
<<
>>
@end lilypond
-Note heads with different note heads may be merged, with the
+Notes with different note heads may be merged, with the
exception of half-note heads and quarter-note heads:
@lilypond[quote,verbatim,relative=2]
@end lilypond
-The collision on the second measure happens because
-@code{\mergeDifferentlyHeadedOn} cannot successfully complete the
-merge when three or more notes line up in the same column -- in
-fact, you will obtain a warning for this reason. To allow the
-merge to work properly, apply a @code{\shift} to the note that
-should not be merged. Here, @code{\shiftOn} is applied to move
-the top @code{g} out of the column, and
-@code{\mergeDifferentlyHeadedOn} works properly.
+The half note and eighth note at the start of the second measure
+are incorrectly merged because @code{\mergeDifferentlyHeadedOn}
+cannot successfully complete the merge when three or more notes
+line up in the same column, and in this case a warning is given.
+To allow the merge to work properly a @code{\shift} must be applied
+to the note that should not be merged. Here, @code{\shiftOn} is
+applied to move the top @notation{g} out of the column, and
+@code{\mergeDifferentlyHeadedOn} then works properly.
@lilypond[quote,relative=2,verbatim]
<<
four) have @code{\shiftOn}. @code{\shiftOnn} and
@code{\shiftOnnn} define further shift levels.
-Notes are only merged if they have opposing stem directions (i.e., in
+Notes are only merged if they have opposing stem directions (e.g. in
@code{Voice} 1 and 2).
gets a slightly wrong offset because of the different width of the
half note head symbol.
-@c investigate! Sometimes it works, sometimes not. --FV
+@ignore
+@c TODO investigate! Sometimes it works, sometimes not. --FV
The requirements for successfully merging different note heads that
are at the same time differently dotted are not clear.
+@end ignore
There is no support for chords where the same note occurs with
different accidentals in the same chord. In this case, it is
@knownissues
+@code{\partcombine} can only accept two voices.
+
When @code{printPartCombineTexts} is set, if the two voices play
the same notes on and off, the part combiner may typeset @code{a2}
more than once in a measure.
@code{\partcombine} cannot be inside @code{\relative}.
Internally, the @code{\partcombine} interprets both arguments as
-@code{Voice}s named @code{one} and @code{two}, and then decides
-when the parts can be combined. Consequently, if the arguments
-switch to differently named @rinternals{Voice} contexts, the
-events in those will be ignored.
-
-@c IIRC in users list someone pointed out more issues. TODO: lookup FV
+@code{Voice}s and decides when the parts can be combined. When they have
+different durations they cannot be combined and are given the names
+@code{one} and @code{two}. Consequently, if the arguments switch to
+differently named @rinternals{Voice} contexts, the events in those will
+be ignored. Likewise, partcombining isn't designed to work with lyrics;
+when one of the voices is explicitly named in order to attach lyrics to
+it, the partcombining stops working.
+
+@code{\partcombine} only observes onset times of notes. It cannot
+determine whether a previously started note is playing or not, leading
+to various problems.
@node Writing music in parallel
projects / lilypond.git / blobdiff