+
+@node Automatic notation
+@section Automatic notation
+
+This section describes how to change the way that accidentals and
+beams are automatically displayed.
+
+@menu
+* Automatic accidentals::
+* Setting automatic beam behavior::
+@end menu
+
+@node Automatic accidentals
+@subsection Automatic accidentals
+@cindex Automatic accidentals
+
+Common rules for typesetting accidentals have been placed in a
+function. This function is called as follows
+
+@funindex set-accidental-style
+@example
+#(set-accidental-style 'STYLE #('CONTEXT#))
+@end example
+
+The function can take two arguments: the name of the accidental style,
+and an optional argument that denotes the context that should be
+changed. If no context name is supplied, @code{Staff} is the default,
+but you may wish to apply the accidental style to a single @code{Voice}
+instead.
+
+@c TODO: we should create a very clear example, and show every
+@c accidental style on that example (with the example specially
+@c constructed so that it illustrates all the differences). -gp
+
+The following accidental styles are supported
+@table @code
+@item default
+This is the default typesetting behavior. It corresponds
+to 18th century common practice: Accidentals are
+remembered to the end of the measure in which they occur and
+only on their own octave.
+
+@item voice
+The normal behavior is to remember the accidentals on
+Staff-level. This variable, however, typesets accidentals
+individually for each voice. Apart from that, the rule is similar to
+@code{default}.
+
+As a result, accidentals from one voice do not get canceled in other
+voices, which is often an unwanted result
+
+@lilypond[quote,ragged-right,relative=1,fragment,verbatim]
+\new Staff <<
+ #(set-accidental-style 'voice)
+ <<
+ { es g } \\
+ { c, e }
+>> >>
+@end lilypond
+
+The @code{voice} option should be used if the voices
+are to be read solely by individual musicians. If the staff is to be
+used by one musician (e.g., a conductor) then
+@code{modern} or @code{modern-cautionary}
+should be used instead.
+
+@item modern
+@funindex modern style accidentals
+This rule corresponds to the common practice in the 20th century. This rule
+prints the same accidentals as @code{default}, but temporary
+accidentals also are canceled in other octaves. Furthermore,
+in the same octave, they also get canceled in the following
+measure
+
+@lilypond[quote,ragged-right,fragment,verbatim]
+#(set-accidental-style 'modern)
+cis' c'' cis'2 | c'' c'
+@end lilypond
+
+@item @code{modern-cautionary}
+@funindex modern-cautionary
+This rule is similar to @code{modern}, but the @q{extra} accidentals
+(the ones not typeset by @code{default}) are typeset as cautionary
+accidentals. They are printed in reduced size or with parentheses
+@lilypond[quote,ragged-right,fragment,verbatim]
+#(set-accidental-style 'modern-cautionary)
+cis' c'' cis'2 | c'' c'
+@end lilypond
+
+@funindex modern-voice
+@item modern-voice
+This rule is used for multivoice accidentals to be read both by musicians
+playing one voice and musicians playing all voices. Accidentals are
+typeset for each voice, but they @emph{are} canceled across voices in
+the same @internalsref{Staff}.
+
+@funindex modern-voice-cautionary
+@item modern-voice-cautionary
+This rule is the same as @code{modern-voice}, but with the extra
+accidentals (the ones not typeset by @code{voice}) typeset
+as cautionaries. Even though all accidentals typeset by
+@code{default} @emph{are} typeset by this variable,
+some of them are typeset as cautionaries.
+
+@item piano
+@funindex piano accidentals
+This rule reflects 20th century practice for piano notation. Very similar to
+@code{modern} but accidentals also get canceled
+across the staves in the same @internalsref{GrandStaff} or
+@internalsref{PianoStaff}.
+
+@item piano-cautionary
+@funindex #(set-accidental-style 'piano-cautionary)
+Same as @code{#(set-accidental-style 'piano)} but with the extra
+accidentals typeset as cautionaries.
+
+@item no-reset
+@funindex no-reset accidental style
+This is the same as @code{default} but with accidentals lasting
+@q{forever} and not only until the next measure
+@lilypond[quote,ragged-right,fragment,verbatim,relative=1]
+#(set-accidental-style 'no-reset)
+c1 cis cis c
+@end lilypond
+
+@item forget
+This is sort of the opposite of @code{no-reset}: Accidentals
+are not remembered at all -- and hence all accidentals are
+typeset relative to the key signature, regardless of what was
+before in the music
+
+@lilypond[quote,ragged-right,fragment,verbatim,relative=1]
+#(set-accidental-style 'forget)
+\key d\major c4 c cis cis d d dis dis
+@end lilypond
+@end table
+
+
+@seealso
+
+Program reference: @internalsref{Accidental_engraver},
+@internalsref{Accidental}, and @internalsref{AccidentalPlacement}.
+
+
+@refbugs
+
+Simultaneous notes are considered to be entered in sequential
+mode. This means that in a chord the accidentals are typeset as if the
+notes in the chord happen one at a time, in the order in which
+they appear in the input file. This is a problem when accidentals
+in a chord depend on each other,
+which does not happen for the default accidental style. The problem
+can be solved by manually inserting @code{!} and @code{?} for the
+problematic notes.
+
+
+@node Setting automatic beam behavior
+@subsection Setting automatic beam behavior
+
+@funindex autoBeamSettings
+@funindex (end * * * *)
+@funindex (begin * * * *)
+@cindex automatic beams, tuning
+@cindex tuning automatic beaming
+
+@c [TODO: use \applyContext]
+
+In normal time signatures, automatic beams can start on any note but can
+only end in a few positions within the measure: beams can end on a beat,
+or at durations specified by the properties in
+@code{autoBeamSettings}. The properties in @code{autoBeamSettings}
+consist of a list of rules for where beams can begin and end. The
+default @code{autoBeamSettings} rules are defined in
+@file{scm/@/auto@/-beam@/.scm}.
+
+In order to add a rule to the list, use
+@example
+#(override-auto-beam-setting '(be p q n m) a b [context])
+@end example
+
+@itemize @bullet
+
+@item @code{be} is either "begin" or "end".
+
+@item @code{p/q} is the duration of the note for which you want
+to add a rule. A beam is considered to have the duration of its
+shortest note. Set @code{p} and @code{q} to @code{'*'} to
+have this apply to any beam.
+
+@item @code{n/m} is the time signature to which
+this rule should apply. Set @code{n} and @code{m} to @code{'*'}
+to have this apply in any time signature.
+
+@item @code{a/b} is the position in the bar at which the beam should
+begin/end.
+
+@item @code{context} is optional, and it specifies the context at which
+the change should be made. The default is @code{'Voice}.
+@code{#(score-override-auto-beam-setting '(A B C D) E F)} is equivalent to
+@code{#(override-auto-beam-setting '(A B C D) E F 'Score)}.
+
+@end itemize
+
+For example, if automatic beams should always end on the first quarter
+note, use
+
+@example
+#(override-auto-beam-setting '(end * * * *) 1 4)
+@end example
+
+You can force the beam settings to only take effect on beams whose shortest
+note is a certain duration
+
+@lilypond[quote,fragment,ragged-right,verbatim,relative=2]
+\time 2/4
+#(override-auto-beam-setting '(end 1 16 * *) 1 16)
+a16 a a a a a a a |
+a32 a a a a16 a a a a a |
+#(override-auto-beam-setting '(end 1 32 * *) 1 16)
+a32 a a a a16 a a a a a |
+@end lilypond
+
+You can force the beam settings to only take effect in certain time
+signatures
+
+@lilypond[quote,fragment,ragged-right,verbatim,relative=2]
+\time 5/8
+#(override-auto-beam-setting '(end * * 5 8) 2 8)
+c8 c d d d
+\time 4/4
+e8 e f f e e d d
+\time 5/8
+c8 c d d d
+@end lilypond
+
+You can also remove a previously set beam-ending rule by using
+
+@example
+#(revert-auto-beam-setting '(be p q n m) a b [context])
+@end example
+
+@noindent
+be, p, q, n, m, a, b and context are the same as above. Note that the
+default rules are specified in @file{scm/@/auto@/-beam@/.scm},
+so you can revert rules that you did not explicitly create.
+
+@lilypond[quote,fragment,ragged-right,verbatim,relative=2]
+\time 4/4
+a16 a a a a a a a a a a a a a a a
+#(revert-auto-beam-setting '(end 1 16 4 4) 1 4)
+a16 a a a a a a a a a a a a a a a
+@end lilypond
+
+The rule in a revert-auto-beam-setting statement must exactly match the
+original rule. That is, no wildcard expansion is taken into account.
+
+@lilypond[quote,fragment,ragged-right,verbatim,relative=2]
+\time 1/4
+#(override-auto-beam-setting '(end 1 16 1 4) 1 8)
+a16 a a a
+#(revert-auto-beam-setting '(end 1 16 * *) 1 8) % this won't revert it!
+a a a a
+#(revert-auto-beam-setting '(end 1 16 1 4) 1 8) % this will
+a a a a
+@end lilypond
+
+
+
+@c TODO: old material -- not covered by above stuff, I think.
+If automatic beams should end on every quarter in 5/4 time, specify
+all endings
+@example
+#(override-auto-beam-setting '(end * * * *) 1 4 'Staff)
+#(override-auto-beam-setting '(end * * * *) 1 2 'Staff)
+#(override-auto-beam-setting '(end * * * *) 3 4 'Staff)
+#(override-auto-beam-setting '(end * * * *) 5 4 'Staff)
+@dots{}
+@end example
+
+The same syntax can be used to specify beam starting points. In this
+example, automatic beams can only end on a dotted quarter note
+@example
+#(override-auto-beam-setting '(end * * * *) 3 8)
+#(override-auto-beam-setting '(end * * * *) 1 2)
+#(override-auto-beam-setting '(end * * * *) 7 8)
+@end example
+In 4/4 time signature, this means that automatic beams could end only on
+3/8 and on the fourth beat of the measure (after 3/4, that is 2 times
+3/8, has passed within the measure).
+
+If any unexpected beam behaviour occurs, check the default automatic beam
+settings in @file{scm/@/auto@/-beam@/.scm}
+for possible interference, because the beam
+endings defined there will still apply on top of your own overrides. Any
+unwanted endings in the default vales must be reverted for your time
+signature(s).
+
+For example, to typeset @code{(3 4 3 2)}-beam endings in 12/8, begin
+with
+
+@example
+%%% revert default values in scm/auto-beam.scm regarding 12/8 time
+#(revert-auto-beam-setting '(end * * 12 8) 3 8)
+#(revert-auto-beam-setting '(end * * 12 8) 3 4)
+#(revert-auto-beam-setting '(end * * 12 8) 9 8)
+
+%%% your new values
+#(override-auto-beam-setting '(end 1 8 12 8) 3 8)
+#(override-auto-beam-setting '(end 1 8 12 8) 7 8)
+#(override-auto-beam-setting '(end 1 8 12 8) 10 8)
+@end example
+
+@cindex automatic beam generation
+@cindex autobeam
+@funindex autoBeaming
+@cindex lyrics
+
+If beams are used to indicate melismata in songs, then automatic
+beaming should be switched off with @code{\autoBeamOff}.
+
+
+@refcommands
+
+@funindex \autoBeamOff
+@code{\autoBeamOff},
+@funindex \autoBeamOn
+@code{\autoBeamOn}.
+
+@commonprop
+
+Beaming patterns may be altered with the @code{beatGrouping} property,
+
+@lilypond[quote,verbatim,relative=2,fragment,ragged-right]
+\time 5/16
+\set beatGrouping = #'(2 3)
+c8[^"(2+3)" c16 c8]
+\set beatGrouping = #'(3 2)
+c8[^"(3+2)" c16 c8]
+@end lilypond
+
+
+@refbugs
+
+If a score ends while an automatic beam has not been ended and is
+still accepting notes, this last beam will not be typeset at all. The
+same holds polyphonic voices, entered with @code{<< @dots{} \\ @dots{}
+>>}. If a polyphonic voice ends while an automatic beam is still
+accepting notes, it is not typeset.
+
+