// This is the help file of Bol Processor.
// This version still includes many features from BP2 that haven't been implemented in BP3.
// When editing it, beware that the compiler looks for prefixes. Therefore, if an item is
// the prefix of another one then it should precede it in this file.
⇪ What style of music is BP3 dealing with?
• BP3 is not designed for a particular musical style. It stemmed out of formalizing
music representation and composition tasks in the context of non-western music, notably
North-Indian rhythm. For this reason it focused on text-oriented representations and formal
grammmars. 'Bol Processor' originates from the word 'bol' (Hindi/Urdu 'bolna', to speak)
designating the onomatopeic names of drum strokes in India.
• When MIDI output was designed, elementary musical 'gestures' that produced sounds on drums
were replaced with "sound-objects", i.e. arbitrary sequences of events encoded as MIDI messages.
• Simplified sound-objects named "simple notes" have later been introduced to facilitate work
with western tonal systems in English, French or Indian "note conventions".
• BP3 is now able to deal with polyphony, and does it in a smart way. See "polymetric structures".
• BP3 also deals with incomplete representations of polyrhythmic sequences.
See "period notation".
• BP3 is able to control all MIDI parameters, including continuous parameters such as pitchbend,
polyphonic pressure, panoramic, etc. See "performance controls".
• BP3 has interactive features used in the "improvize mode". It responds to MIDI messages
(see "Interactive mode").
• Thanks to Csound, BP3 bypasses limitations of MIDI, and takes advantage of both environments.
(See "Csound implementation")
⇪ How does the output of BP3 look like?
• There are three representation levels:
1) The symbolic level, at which music is represented as a TEXT score. This score uses either
"simple notes" or "sound-objects" completed with "performance controls".
Polyphonic items use "polymetric expressions".
Sequences may use the "period notation".
2) The graphic level, at which "simple notes" or "sound-objects" are shown with their actual
physical timings.
3) The sound level, a flow of MIDI messages sent in real time to a MIDI device, a MIDI
file or a Csound score.
• Output options are set in the "Settings" window. If "Display items" is checked then
musical items are first displayed as text scores. This is not recommended for long items.
If "Show graphics" is checked then graphic scores are displayed while items are played on the
MIDI output. If none is checked then items are played directly, but for each item the option
is given to display the text score.
• A text score may be displayed in graphic and played on the MIDI output: select the text and do
"Play selection" in the "Action" menu.
⇪ How does the input of BP3 look like?
• A score in text format may be selected and played on the MIDI output: select "Play selection"
in the "Action" menu. Try it for example on "C5 C5 C5 D5 E5_ D5_ C5 E5 D5 D5 C5_ _ _".
• Examples of (less trivial) text format scores are stored in '-da' files that may be loaded to
the "Data" window. There are more examples in the enclosed data-base "TryAppleEvents.fm"
which may be opened under Claris FileMaker Pro.
• A grammar is the formal description of a process producing musical text scores which BP3 is able
to play on its MIDI output. Load for instance '-gr.Mozart' in the "Grammar" window, then
type command-R or select "Produce items" in the "Action" window.
• A script is a sequence of meta-instructions performing all operations automatically in BP2 or BP3.
Scripts are discussed in the initial part ("QuickStart") of the old document:
https://bolprocessor.org/misc/docs/
• MIDI files type 0, 1 or 2 can be imported to create "sound-object prototypes".
• Csound scores can be imported to create "sound-object prototypes".
• BP3 responds to input MIDI messages. See "Interactive mode" and https://bolprocessor.org/real-time-midi/
⇪ Interactive mode
Read https://bolprocessor.org/real-time-midi/
This is the real-time MIDI mode when a MIDI device is connected to an input.
In this mode, BP3 is able to respond in real time to MIDI messages that are assigned certain tasks.
• For instance, instruction (not yet implemented)
Control parameter K1 = #7 channel 16
instructs controller #7 on channel 16 to fix the value of parameter K1.
This parameter may control weights in grammar rules, velocities, etc. (see "Variable arguments")
• A parameter can also be set to the velocity of a NoteOn, for example:
Velocity parameter K1 = C3 channel 16
⇪ Variables
BP3 recognizes strings starting with an uppercase character as "variables" in grammars
or in its glossary. It creates a variable if it is not already there, so be careful
with spelling mistakes.
• You may however start a variable with a lower-case character provided that you write
it between |vertical bars|.
• Variable names may be of any length and may contain any character (standard or
extended), digit, or punctuation symbol in the set: \ - _ # @ % $ " % '
• Examples of well-formed variables:
MyNewTrick Good_enough |behind_the_bars| X67$-J Big@mac The"new"thing
It's_there De_Noël_à_Pâques
Peter-Piper-pick'd-a-pick-of-pickl'd-pepper
• Related topic: "Terminal alphabet"
⇪ Polymetric structures
A structure of "sound-objects" represented as a "polymetric expression".
⇪ Polymetric expressions
• An expression denoting a polyphonic or/and polyrhythmic structure of "sound-objects".
Example:
{C4 D4 E4,G3 E3} (brackets optional) means that "C4 D4 E4" will be played in the same
time as "G3 E3".
• BP3 manages to adjust durations. Here, the duration of each beat is determined by the
first beat "C4 D4 E4", hence three beats. It will be interpreted:
/2 {C4_ D4_ E4_,G3_ _ E3 _ _}
yielding the phase diagram:
C4 _ D4 _ E4 _
G3 _ _ E3 _ _
• BP3 uses the same algorithm to deal with polymetric expressions and with "period notation".
• A polymetric expression can contain another polymetric expression, including expressions in
"period notation".
Try to play: {C4 D4 E4,{G3,C3} E3} for instance [with "English convention" checked
in the 'Misc' menu].
• Many commented examples will be found in "-da.checkPoly".
• Read https://bolprocessor.org/polymetric-structure/
⇪ Undetermined rests
• These are notated '_rest'.
The old notation '…' (be careful: this is a single character, not three periods!)
is still valid, but it is not recommended because of character conversion in HTML docs.
• Undetermined rests are used in fields of "polymetric expressions" or in beats of the
"period notation". The interpreter determines their durations as the ones yielding
the simplest expanded expression.
• For instance, the sequence
a b c d • e _rest f • g h _rest i (also notated a b c d • e … f • g h … i)
will be expanded as:
a b c d • e - _ f • g h - i
• Similarly, the polymetric expression
{3/2 c d e, _rest f g} (also notated {3/2 c d e, … f g})
will be expanded as:
/2 {- _ _ c _ d _ e _,- _ _ _ _ f _ g _}
• Each field of a polymetric expression (or each beat of a sequence) may contain
several undetermined rest. (This is a recent feature). In this case, these rests
share equal durations. For instance,
{C3 D3 B2, _rest C4 D4 _rest B3}
is expanded as:
/8 {C3_ _ _ _ _ _ _ D3_ _ _ _ _ _ _ B2_ _ _ _ _ _ _,
-_ _ C4_ _ _ _ _ D4_ _ _ _ _ -_ _ B3_ _ _ _ _}
in which each rest has a duration of 3/8 beats.
• Read https://bolprocessor.org/polymetric-structure/#undetermined-rests
⇪ Period notation
• Periods are used to indicate 'beats', i.e. sequences of "sound-objects" that are
constrained to equal symbolic durations. For instance,
{C4 D4 E4 • G3 E3} (Brackets {} are optional)
means that "C4 D4 E4" will be played with the same duration as "G3 E3".
• The duration of each beat is determined by the first beat "C4 D4 E4", hence three
time units. It will be interpreted:
/2 C4_ D4_ E4_ • G3_ _ E3_ _
• BP3 uses the same algorithm to deal with period notation and with "polymetric expressions".
Thus, {C4 D4 E4,G3 E3} (the period has been replaced with a comma)
will be interpreted:
/2 {C4_ D4_ E4_,G3_ _ E3_ _}
yielding the phase diagram:
C4 _ D4 _ E4 _
G3 _ _ E3 _ _
• Many commented examples will be found in example file '-da.checkPoly'.
• Read https://bolprocessor.org/polymetric-structure/
⇪ Terminal symbols
See "Terminal alphabet"
⇪ Terminal alphabet
• A 'vocabulary' of arbitrary words (terminal symbols) designating "sound-objects".
• Each word is defined in the 'alphabet' window saved as '-al.filename'.
• A terminal symbol may also be defined at "compile time" if it appears between
single quotes in the grammar, or if it is used in an out-time "sound-object":
<<iAmAnOutTimeSoundObject>>.
• A terminal symbol must start with a lower-case character (a..z) or any symbol in the
set:
ÄÅÇÉÑÖÜáàâäãåçéèêëíìîïñóòôöõúùûüÆæøÀÃÕŒœÿßص∂∑∏πΩƒ∆¥#
• Other characters in a terminal symbol may be any character (a..z, A..Z) or a
character in the above set, or characters in additional set:
0123456789#%@¢£§◊$®©™\'"†°`´¨≠∞±≤≥ªº¿¡√«»“”‘’÷
• The above restrictions do NOT apply to terminal symbols defined between single quotes
in grammars.
• You may define relations (homomorphisms) in a given alphabet. See: "homomorphism".
• Terminal symbols are mapped to "sound-object prototypes" thanks to the information
contained in "-mi.filename". The name of this file should be inserted on top of the
'alphabet' window.
• BP3 also recognizes predefined terminal symbols called "simple notes".
• Related topics: "Variables", "sound-objects".
⇪ Metavariables
See "Wild cards"
⇪ Wild cards
Symbols '?', '?1', '?2', ... '?n' are used as wild cards in grammar rules. They may
be instantiated as a single "terminal symbol", "simple note", "variable", bracket,
"out-time object", "synchronization tag", "time pattern" or "performance control".
• '?' (an old notation) is equivalent to '?1'.
• If the expression contains several wild cards '?n', values are checked for pattern
matching. For instance,
?1 ?3 ?2 ?2 ?1 ? ?3
may be instantiated as a pattern "xyzzxty" in which occurrences of x, y and z must be
identical.
• The same wildcards may be found in the right argument of a rule. For instance, the
following rule will reverse the order of two (distinct) symbols:
?1 ?2 --> ?2 ?1
⇪ Compile time
The time when a grammar is being compiled, or some data is being "tokenized". This may
be opposed to "performance time".
⇪ Tokenized data
Grammars and musical items are represented with reserved words, "terminal symbols"
and variables. Before using them, BP3 replaces them with tokens, i.e. numeric
codes. These codes are not visible to users.
⇪ Performance time
The time when a musical item is being played on the sound output. This may be opposed
to "compile time".
⇪ Out-time sound-object
• It appears between angle brackets: <<this is an out-time sound-object>>.
• It contains the same sequence of events as an ordinary "sound-object", but its duration
is forced to zero. If its label does not appear in the "Terminal alphabet", a new
terminal symbol will be created at "compile time".
⇪ Null string
A string representing an empty sequence (of "sound-objects"). You may use
"nil", "lambda", "empty" or "null" (without quotes) to designate a null string. You
may also leave the space blank. These are three equivalent notations for the same
rule:
S --> nil
S --> lambda
S --> empty
S --> null
S -->
⇪ Simple notes
These are predefined terminal symbols mapped to predefined "sound-objects"
containing only a NoteOn / NoteOn pair of MIDI messages. These "sound-objects"
are relocatable and have pivots at their beginnings. They can be rescaled at will,
they can be truncated or covered by neighbouring "sound-objects". Their "pre-roll" and
"post-roll" settings are nil.
• The conventional 440Hz tone may be written 'A4', 'la3' or 'dha4', depending on the
note convention set in the 'Misc' menu, and the one in the "Tuning" dialog.
• See: "English convention", "French convention", "Indian convention","Key numbers".
⇪ Tuning dialog
This dialog makes it possible to modify the MIDI keyboard mapping and diapason
reference used by Csound.
• Usually, key 60 is assigned to C4 (do3 in French, sa4 in Indian)
⇪ Relocatable sound-object
A "sound-object" that may be relocated by the "time-setting algorithm".
⇪ Sound objects
See "Sound-objects"
⇪ Sound-objects
See the reference manual and publications.
• In short, a sound-object in BP3 is a sequence of 'elementary' events, such as MIDI
or Csound instructions.
• A typical simple sound-object is a "simple note", i.e. a NoteOn/NoteOff
pair on the same MIDI key and channel.
• Sound-objects are labelled as "terminal symbols". Each object is mapped to
a unique "sound-object prototype" bearing the same name, which defines its metric
and topologic properties.
• Example: https://bolprocessor.org/interactive-improvisation/
⇪ Sound-object prototypes
These contain information about "sound-objects" bearing the same name: the list of
elementary events, and metric and topologic properties used by the "time-setting algorithm".
• Elementary events may be MIDI events, Csound events, or both.
• Read https://bolprocessor.org/check-bp3/#sound-object-prototypes
⇪ Time-setting algorithm
An algorithm used by BP3 to calculate the timings of elementary events (e.g.
MIDI or Csound events) in a musical item. It takes into account the properties of
"sound-objects" (defined by their "sound-object prototypes") and may relocate or
truncate objects in order to satisfy all constraints arising therefrom.
⇪ Homomorphism
This is an optional relation on the "terminal alphabet" used by a grammar. It is
defined over all the terminal symbols and identified by a label. For
instance, let us call TRANS the one-semitone upward transposition in an alphabet of
notes. The alphabet file (saved as "-al.mynotes") would begin like this:
TRANS
do0 --> do#0 --> re0 --> re#0 etc... --> si9
• If a "terminal alphabet" uses no homomorphism then arrows "-->" should of course not
be found.
• You can define several homomorphisms in the same alphabet. Separate them by lines
of hyphens (just like "subgrammars").
• If an homomorphism has been declared, the last terminal of a line is mapped to
itself, unless it is defined cyclically. In the example above it would mean that
si9 --> si9. But we could as well use a cyclic definition:
do0 --> do#0 --> re0 --> re#0 etc... --> si9 --> do0
⇪ Derivation mode
See "Subgrammar type" and "Rule derivation mode"
⇪ Subgrammars
A grammar may be "sliced" in several subgrammars that will be applied successively
to the "work string" for producing derivations. A new subgrammar is applied only
once there is no more candidate rule in the current subgrammar. You may however
bypass this rule by using jumps like _goto() or _failed().
• In analysis (parsing) mode, subgrammars are applied in the reverse order.
⇪ Subgrammar type
The strategy followed by the "inference engine" to produce or analyze an item using
the rules of this "subgrammar". See: "RND", "ORD", "LIN", "SUB", "SUB1".
⇪ Inference engine
The term is borrowed from expert systems. It designates the process by which rules
in a grammar are selected and and applied by the "work string". The inference engine
may perform a "production" (starting from a start string, usually 'S') or a
"membership test" (analysis, parsing) assessing whether a given string belongs to
the language generated by the grammar.
• "Production" is also called "modus ponens", and analysis "modus tollens", but this
terminology is more appropriate for inference engines based on logical inference.
⇪ Production
See "Inference engine".
⇪ Analysis
See "Inference engine".
⇪ Parsing
See "Inference engine".
⇪ Rule derivation mode
In "production", there are three derivation modes for rules in a "subgrammar":
• RND (default mode): the position of the derivation is chosen randomly
in the "work string";
• LEFT: the position of the derivation is the leftmost occurrence of the left argument
of this rule;
• RIGHT: the position of the derivation is the rightmost occurrence of the left argument
of this rule;
• If a "subgrammar" is of "LIN" type then all rules are applied in "LEFT" mode.
⇪ Programmed grammars
See "flags"
⇪ Flags
Flags are integer global variables indicating particular states during production by
a grammar. This is a generalisation of "programmed grammars".
• A rule like: X --> a /myflag/
creates a flag labelled 'myflag' and set its value to 1.
• A rule like: /myflag/ X --> a
will only be candidate if 'myflag' has previously be created and its value is positive.
• Unlike in previous versions of BP2, the flag value is not modified unless specified:
/myflag - 1/ X --> a
• Flags may be positive or negative in range [-32768,32767].
• Flag names may contain up to 30 characters. Any character may be used except:
/ + - = < > ≤ ≥ ≠ and tabulations or spaces
• Other flag features:
X --> a /myflag +3/ increments the value of 'myflag' by 3 units.
X --> a /myflag -5/ decrements the value of 'myflag' by 5 units. Negative values
are accepted.
X --> a /myflag = 3/ assigns 3 to 'myflag'.
/myflag +3/ X --> a checks that 'myflag' is positive, and if so, makes the rule
candidate. When the rule is fired, the value of 'myflag' is incremented by 3 units.
/myflag -5/ X --> a checks that 'myflag' is positive, and if so, makes the rule
candidate. When the rule is fired, the value of 'myflag' is incremented by 5 units.
/myflag = 3/ X --> a checks that 'myflag' is equal to 3, and if so, makes the rule
candidate.
/myflag ≠ 3/ X --> a checks that 'myflag' is unequal to 3, and if so, makes the rule
candidate.
/myflag < 3/ X --> a checks that 'myflag' is smaller than 3, and if so, makes the rule
candidate.
/myflag > 3/ X --> a checks that 'myflag' is greater than 3, and if so, makes the rule
candidate.
/myflag ≤ 3/ X --> a checks that 'myflag' is smaller or equal to 3, and if so, makes
the rule candidate.
/myflag ≥ 3/ X --> a checks that 'myflag' is greater or equal to 3, and if so, makes
the rule candidate.
• Be careful that '=' is the assignment operator if found in the right argument of a
rule, and a comparison operator otherwise.
• A rule may contain several flag conditions, e.g.:
/myflag ≥ 3/ /myflag < 20/ /otherflag = 4/ X --> a
• In assignments and comparisons, numbers may be replaced with other flags
or global variables K1, K2, etc., e.g.:
X --> a /flag1 = K1/ /flag2 = flag1/
/flag1 > K19/ X --> b
/flag2 ≠ flag3/ X --> c
• See for example '-gr.tryflag', '-gr.tryflag2', '-gr.tryflag3'
• Note: flag syntax is likely to evolve but it will remain consistent with this one.
⇪ BP grammar
See "true BP grammar"
⇪ RND [Subgrammar type or rule derivation mode]
• As a "subgrammar" type, it means that when producing an item rules may be used in
a random order. When analysing an item, RND works like ORD.
• As a rule derivation mode, it means that the position of the derivation, when
producing items, may be choosen randomly. In parsing mode (analysis), position is
tried from right to left. (See rightmost context-sensitive derivation in publications)
⇪ LEFT [Rule derivation mode]
When producing an item, this rule will be applied to the leftmost occurrence of
the left argument in the "work string". In parsing mode, the rightmost occurrence
of the right argument will be searched.
⇪ Work string
The string representing the musical item being processed by the grammar. In "production"
mode, it starts with the start string 'S'. In analysis (parsing) mode, it starts
with the string under analysis.
⇪ RIGHT [Rule derivation mode]
When producing an item, this rule will be applied to the rightmost occurrence of
the left argument in the "work string". In parsing mode, the leftmost occurrence
of the right argument will be searched.
⇪ ORD [Subgrammar type]
A "subgrammar" the rules of which should be applied in (top-down) order in "production",
and bottom-up order in analysis (parsing).
• Each rule is applied repeatedly until it is no longer candidate. There is no random choice.
⇪ LIN [Subgrammar type]
A "subgrammar" using (context-sensitive) leftmost derivation in "production", and
(context-sensitive) rightmost derivation in analysis. See reference manual and
related publications.
⇪ SUB [Subgrammar type]
A "subgrammar" using (context-sensitive) substitutions.
A substitution is the simultaneous application of all candidate
rules in the "subgrammar" until no rule is candidate.
• This type works in "production" mode only.
⇪ SUB1 [Subgrammar type]
Similar to SUB, but substitutions are performed only once.
• This type works in "production" mode only.
⇪ POSLONG [Subgrammar type]
A "subgrammar" in which the candidate rule is selected for the (1) leftmost and (2) longest occurrence
of its left argument in the "work string".
• This type works in "production" mode only.
• If several rules are candidate the uppermost one is selected. There is no random choice.
⇪ Glossary
• A glossary is a special "subgrammar" that is applied to the "work string" just before
it is played on the MIDI outup or displayed on the graphic window. A convenient
use of glossary is to define instructions that are particular to the sound system.
• For instance, -gl.GeneralMIDI contains the code needed to select sound 'patches' on
any synthesizer in the "General MIDI" standard.
⇪ TEMPLATES: [Subgrammar type]
A list of 'templates' used by a true BP grammar. See reference manual.
⇪ REC
Starts/stops recording actions as a script (in the script window).
⇪ _randomize
A "grammar procedure" or a "tool".
• On top of a "subgrammar", it picks up an arbitrary seed for the sequence of random numbers
so that all subsequent random choices become unpredictable.
This is equivalent to clicking the "New seed" button in the "Random sequence" dialog,
or calling "Randomize" in a script.
• If "_randomize" is found in an item being played, the sequence of random numbers is
shifted to an arbitrary position, causing unpredictable choices to occur in "_rndseq",
"_rndtime", etc.
• The effect of "_randomize" is cancelled by "_srand".
• Related topics: "_srand", "Randomize", "Reset random sequence", "Set random seed",
"New seed".
⇪ _goto(igram,irul) [Grammar procedure]
This procedure is found in the right argument of a rule.
• _goto(igram,irul) will cause BP3 to jump to "subgrammar" igram, rule irul, when the rule
that contains it has been applied. If (igram,irul) does not point at a candidate rule,
BP3 will either execute a "_failed" conditional jump or search a candidate rule in
subgrammar igram. If none is found it will jump to subgrammar igram+1, etc. as usual.
• _goto(igram,0) causes to jump to "subgrammar" igram and go on selecting rules according to the
subgrammar type.
⇪ _failed(igram,irul) [Grammar procedure]
This procedure is found in the right argument of a rule.
• A conditional jump to another "subgrammar" or another specific rule in a
"subgrammar". Its syntax is: _failed(igram,irul) in which igram and irul have the
same meanings as in "_goto".
• The jump will be performed if the rule was selected by a preceding "_goto" or "_failed"
and it is not a candidate rule.
⇪ _repeat(n) [Grammar procedure]
This procedure is found in the right argument of a rule.
• Indicates that the current rule should be tried n times.
• Alternate syntaxes are _repeat(Kx) and _repeat(Kx = n) where Kx is a parameter
that may be assigned a fixed value (Kx = n) and/or controlled in real time by an
external MIDI device.
⇪ _stop [Grammar procedure]
When encountered in "production", forces production to pause
⇪ _printOn [Grammar procedure]
When encountered in "production", starts the display of various stages of the "work string"
in the "Trace" window
⇪ _printOff [Grammar procedure]
Cancels the effect of "_printOn"
⇪ _print [Grammar procedure]
When encountered in "production", displays the "work string" in the "Trace" window
⇪ _stepOn [Grammar procedure]
When encountered in "production", starts the "step-by-step" mode
⇪ _stepOff [Grammar procedure]
Cancels the effect of "_stepOn".
⇪ _traceOn [Grammar procedure]
When encountered in "production", starts displaying various stages of the "work string"
and traces of all applied rules
⇪ _traceOff [Grammar procedure]
Cancels the effect of "_traceOn".
⇪ _destru [Grammar procedure]
When encountered in "production", destroys the structure of the "work string", notably
removing parentheses indicating repetitions
⇪ _mm(x) [Grammar procedure]
Sets up the metronome to the 'x' value (in beats per minute)
• This is also a "performance control"
• _mm() should not be used more than once in a selected item or in a grammar, failing to
which the latest value will be used.
⇪ _srand(x) [Grammar procedure or performance control]
Sets the random generator's seed to 'x' and resets the random sequence.
• On top of a grammar, resetting will take place during computation, before any rule of
the grammar is applied.
• If placed just before "_rndseq", _srand will force the order of the sequence to a preset
one that depends on the value of 'x'.
• Values of 'x' are arbitrary, use them only to mark identical sequences or derivations in
grammars. The range is 0..32767.
• The effect of _srand(x) is cancelled by "_randomize".
• Using _srand(x) is a proper way of repeating random patterns. However, it is not
certain that these patterns will remain the same ones each time BP3 is run.
Sequences of random choices depend on machines, system versions, BP3 versions,
and the grammar itself.
• Related topics: "_randomize", "Randomize", "Reset random sequence", "Set random seed",
"New seed".
⇪ OFF (quantization)
Cancels the effect of ON (quantization).
⇪ ON (quantization)
When checked, BP3 will use the quantization setting (in milliseconds) to simplify
tables containing "sound-object" structures (the phase diagram, see manual).
• The result is a saving of memory space and "computation" time making it possible to
compute very complex items.
⇪ _capture(x) [Performance control]
In real-time MIDI, if Interactive mode is on, _capture(x) sets the machine to record incoming MIDI events and store them in a "capture" file. Parameter 'x' (range 1 to 127) is an arbitrary flag indicating the source. The command _capture(0) ends the capture.
Read explanations: https://bolprocessor.org/capture-midi-input/
⇪ _script(scriptline) [Performance control]
The script line will be executed at "performance time".
⇪ _scale(name,blockkey) [Performance control]
Read https://bolprocessor.org/check-midi-microtonality/
If microtonal scales have been defined in the ‘-to’ Tonality resource file, they can be selected as follows:
• By default, a 12-tone equal-tempered scale is used.
• "name" is the label of the scale, by default "scale_1", "scale_2" etc. (no space)
• "blockkey" specifies the key of the note whose frequency should always match equal-temperament. For instance, if blockkey = 69 then 'A4' will stick to diapason (A4 frequency). Default value of 'blockkey' is stored in the settings.
• If blockkey is 0 in a _scale() statement, it is set to its value found in the settings, or by default 60.
• In a _scale() statement, blockkey may be specified as a note, e.g. 'G4', instead of a key number. Beware of using the same note convention as in the grammar...
• _scale(0,blockkey) will reset the scale to equal-tempered, in which case 'blockkey' is irrelevant.
• Values of 'scale' and 'blockkey' are carried through fields of polymetric expressions and not influenced by _chan()
⇪ MIDI format
Musical Instrument Digital Interface: a standard for communications between between
computers and electronic musical instruments.
⇪ Csound format
• Csound uses two text files as an input: an 'orchestra' file describing sound production
procedures (a set of virtual instruments), and a 'score' file describing sound events.
• The Bol Processor produces Csound score files using its own representation
of musical items, grammars and scripts, and a minimum amount of information about
the arguments expected by instruments in the Csound orchestra file.
• Related topic: "Csound implementation"
⇪ Expand selection window «windowname»
Displays selected "polymetric structure" as interpreted by BP3.
• Two equivalent interprations are displayed. The first one is the most compact
representation (the one used internally by BP3). The second one is the complete
expression, containing no explicit "tempo marker". The first expression may
imply a rescaling.
• For instance,
{a b,c d e}
is interpreted:
[Rescaled, "dilation ratio" = 2] /2 {a b, /3 c d e}
/3 {a_ _ b_ _,c_ d _ e_}
• This is also a script command.
⇪ Show periods
Rewrites the selection taking into account the "section header".
⇪ Section headers
If a, b, c are sound objects, a sequence may be notated:
3+4+2/4 abbabccabcca /3 abcccbaab /1 bbb
• Expression "3+4+2", called the "section header", means that sections of the meter
contain 3, 4 and 2 beats.
• The musical example starts at speed 4, goes on at speed 3 and ends up at speed 1.
• If "Show periods" is applied to this item, the new display will be:
abba.bcca.bcca.¬
abc.ccb.aab.b.¬
b.b
• Thus, periods indicate beat delimitations and line breaks '¬' sections.
• Note that there must be a period before a line break, otherwise the last beat would be
merged with the first one of the next line.
• The old notation "3/4/2/4 abbabccabcca /3 abcccbaab /1 bbb" is no more valid.
⇪ Italian/Spanish/French convention
Use Italian/Spanish/French names of notes: dob, do, do#, reb, re, re#, mib, mi, mi#, fab, fa, fa#, solb,
sol, sol#, lab, la, la#, sib, si, si# and octave numbers such that la3 = 440 Hz.
• Related topic: "Tuning"
⇪ English convention
Use English names of notes: Cb, C, C#, Db, D, D#, Eb, E, E#, Fb, F, F#, Gb, G,
G#, Ab, A, A#, Bb, B, B# and octave numbers such that A4 = 440 Hz
• Related topic: "Tuning"
⇪ Indian convention
Use (modified) Indian names of notes: sab, sa, sa#, reb, re, re#, gab, ga, ga#, mab, ma, ma#, pab,
pa, pa#, dhab, dha, dha#, nib, ni, ni# and octave numbers such that dha4 = 440 Hz.
• Related topic: "Tuning"
⇪ Key numbers
Use MIDI key numbers to represent notes, for example 'key#60' is middle C.
• Related topic: "Tuning"
⇪ Note conventions
Conventions used for writing "simple notes".
• Related topics:
"Note convention = English"
"Note convention = Italian/Spanish/French"
"Note convention = Indian"
"Note convention = key numbers"
"Tuning"
⇪ Quantization «long» milliseconds
The minimum significant duration. It is convenient to set quantization to the largest
acceptable value in order to save "computation" time and space.
• Note that quantization in BP3 has no effect on long-term accuracy.
⇪ Quantize OFF
Cancels the effect of "Quantize ON".
⇪ Quantize ON
See "Quantization".
⇪ Reset random sequence
Reseeds the random number generator with the value specified by "Set random seed"
• Related topics: "_srand", "_randomize", "Randomize", "Set random seed", "New seed".
⇪ _smooth
• Related topic: "Smooth time"
⇪ Smooth time
Sets time to smooth.
• This means that time streaks will not be generated by the metronome, but by the
first sequence of objects. This is often associated with "time patterns".
• Related topic: "Striated time"
⇪ _striated
• Related topic: "Striated time"
⇪ Striated time
Sets time to striated.
• This means that the metronome will generate time streaks on which the pivots of
"sound-objects" may be placed.
• Related topic: "Smooth time"
⇪ Wait for «key stroke or MIDI event»
To define the wait event, the easiest is to check 'REC' in the script window,
then click 'WAIT FOR:'.
• Examples of correct syntax:
Wait for Eb4 channel 1 -- waiting for a NoteOn on the MIDI input, key E flat,
octave 4, channel 1
Wait for mib3 channel 1 -- identical to the third one, in Italian/Spanish/French convention
Wait for space -- waiting for the space bar to be depressed (not with BP3)
Wait for Start -- waiting for a 'Start' MIDI message
Wait for Continue -- waiting for a 'Continue' MIDI message
Wait for Stop -- waiting for a 'Stop' MIDI message
• Clicking the mouse exits any the wait loop.
⇪ Split terminal symbols
When checked, inserts spaces between terminal symbols in items produced by the grammar.
⇪ Split |variables|
When checked, marks variables with vertical lines in items produced by the grammar.
• This is only useful with black and white display.
⇪ Time patterns
Sequences of time intervals characterized by precise ratios, to be used in "smooth time".
• These are processed like (codeless) "sound-objects". They are usually put together in
the first field of a "polymetric expression".
• Type them at the bottom of a grammar or alphabet.
• Example:
TIMEPATTERNS:
t1= 1/1 t2 = 3/2 t3 = 4/3
t4 = 1/2
-----------------------
• Time patterns always start with 't' followed with digits. Expressions may contain an
integer or an integer ratio. An example of polymetric expression using these time
patterns is: {t1 t3 t4, do5 re5 mi5 fa5 - la5} (See project '-gr.tryTimePatterns')
⇪ _chan(x) [Performance control]
Sets current channel to x.
• Range of x is 1..16
• The argument may also be Kx. See "variable arguments". In this case it may be
controlled by a MIDI device during the performance.
⇪ _ins(x)
Sets current Csound instrument to x.
• Range of x is 0..127
• x may also be the name of the instrument as defined in the "Csound instrument file".
• The argument may also be Kx. See "variable arguments".
⇪ _part(x)
Sets current part of code to x.
• A part is generally sent to specific MIDI instrument(s), as instructed by the MIDI output filters on the interface.
• Range of x is 1..12
• Read https://bolprocessor.org/real-time-midi/#the-_part-command
⇪ _vel(x) [Performance control]
Sets velocity of following "sound-object" to x.
• Range of x is 0..127
• The argument may also be Kx. See "variable arguments". In this case it may be
controlled by a MIDI device during the performance.
⇪ _rndvel(x) [Performance control]
Assigns random fluctuations in range +/- x to the velocities of following "sound-objects"
or "simple notes".
• Range of x is 0..64
• The argument may also be Kx. See "variable arguments". In this case it may be
controlled by a MIDI device during the performance.
• Related topics: "_rndtime", "_srand".
⇪ _rndtime(x) [Performance control]
Assigns random fluctuations in range +/- x to the timings of following "sound-objects"
or "simple notes".
• 'x' is the fluctuation in milliseconds.
• Range of x is 0..32767. Values less than the "quantization" will produce no effect.
• Related topics: "_rndvel", "_srand".
⇪ _velcont [Performance control]
Indicates that velocity should change continuously. [Equivalent to "_velstep" in
current version]
⇪ _velstep [Performance control]
Indicates that velocity should change stepwise between two specified values.
⇪ _script(x) [Performance control]
Indicates that script line 'x' should be executed just before the next "sound-object"
or "simple note" is played.
⇪ _mod(x) [Performance control]
Indicates that modulation should be set to x.
⇪ _modstep [Performance control]
Indicates that modulation should change stepwise between two specified values.
⇪ _modcont [Performance control]
Indicates that modulation should change continuously.
• See "Continuous performance control"
⇪ _pitchbend(x) [Performance control]
Controls pitchbend in two possible ways. If _pitchrange(r) is not specified or is null
for the current MIDI channel, then x is the actual MIDI value (range 0..16383).
• If _pitchrange(r) is specified, then x is the correction in cents.
(Also see "_pitchrange")
⇪ _fixed [Performance control]
_fixed(param) indicates that "Performance parameter" 'param' does not vary.
• This is the default setting for any performance parameter.
• Related topics: "_step", "_cont", "_value", "Performance parameter".
⇪ _step [Performance control]
_step(param) indicates that "Performance parameter" 'param' varies stepwise.
• Related topics: "_fixed", "_cont", "_value", "Performance parameter".
⇪ _cont [Performance control]
_cont(param) indicates that "Performance parameter" 'param' varies continuously.
• The default setting for any performance parameter is stepwise.
• Related topics: "_fixed", "_step", "_value", "Performance parameter".
⇪ _value [Performance control]
_value(param,x) assigns numeric value 'x' to "Performance parameter" 'param'.
• The value may be an integer or floating-point relative number.
• In the present version only 256 '_value(…,x)' statements can be handled with
different 'x' values.
• Related topics: "_fixed", "_step", "_cont", "Performance parameter".
⇪ Performance parameter
Up to 256 parameters with arbitrary names may be handled by BP3 apart from the
predefined ones: pitchbend, pressure, modulation, etc. which generate
MIDI messages and Csound events.
• An arbitrary parameter is automatically created when refered to in a "_value", "_fixed",
"_cont" or "_step" statement.
• These parameters have no effect on the MIDI output. A parameter is used by a Csound
instrument if its name is found as a "Parameter name" in the Csound instrument
description.
(See "Csound instruments" in the "Ouput" menu and click the "MORE…" button)
• If a sequence of sound-objects or simple notes is preceded with '_cont(param)',
the parameter 'param' will be interpolated as explained in
"Continuous performance control". In this case, it advisable to use two
indexes for passing the start and end values over to the instrument.
(See "Start index" and "End index")
• A typical expression containing a variable parameter named 'blurb':
_cont(blurb) _value(blurb, 154.2) A4 B4 C4 _value(blurb, -21) D4
• Related topics: "_fixed", "_step", "_cont", "_value", "Parameter name".
⇪ _pitchstep [Performance control]
Indicates that pich should change stepwise between two specified values.
⇪ _pitchcont [Performance control]
Indicates that pich should change continuously between two specified values.
• See "Continuous performance control"
⇪ _press(x) [Performance control]
Controls channel pressure on current channel.
• Range of x is 0..127
• The argument may also be Kx. See "variable arguments".
⇪ _presstep [Performance control]
Indicates that channel pressure should change stepwise between two specified values.
⇪ _presscont [Performance control]
Indicates that channel pressure should change continuously between two specified values.
• See "Continuous performance control"
⇪ _switchon(i,c) [Performance control]
Sets controller i to 127 on channel c. For instance, if controller 64 is the hold
pedal, this command will have the same effect as pushing the pedal.
• The range for 'i' is 64 to 95.
⇪ _switchoff(i,c) [Performance control]
Sets controller i to 0 on channel c. For instance, if controller 64 is the hold pedal,
this command will have the same effect as releasing the pedal.
• The range for 'i' is 64 to 95.
⇪ _volumestep [Performance control]
Indicates that volume should change stepwise between two specified values.
⇪ _legato(x) [Performance control]
Indicates that durations of notes in the following sequence will be increased by x% to produce legato effect.
⇪ _staccato(x) [Performance control]
Indicates that durations of notes in the following sequence will be decreased by x% to produce staccato effect.
⇪ _articulstep [Performance control]
Indicates that articulation (legato-staccato) of notes in the following sequence should change stepwise between two
specified values.
⇪ _articulcont [Performance control]
Indicates that articulation (legato-staccato) of notes in the following sequence should change continuously between two
specified values.
⇪ _velfixed [Performance control]
Cancels the effect of _velcont or _velstep.
⇪ _modfixed [Performance control]
Cancels the effect of _modcont or _modstep.
⇪ _pitchfixed [Performance control]
Cancels the effect of _pitchcont or _pitchstep.
⇪ _pressfixed [Performance control]
Cancels the effect of _presscont or _presstep.
⇪ _volumefixed [Performance control]
Cancels the effect of _volumecont or _volumestep.
⇪ _articulfixed [Performance control]
Cancels the effect of _articulcont or _articulstep.
⇪ _panfixed [Performance control]
Cancels the effect of _pancont or _panstep.
⇪ _pitchrange(x) [Current channel] [Performance control]
Sets the range of pitchbend control to ± x cents on the current channel. This value
should reflect the range on the current 'patch' of the MIDI expander.
• For instance, _pitchrange(300) means that pitch modifications will be in the range of
three semitones above and below the average value.
• Once _pitchrange(x) has been specified on a MIDI channel, subsequent _pitchbend(y)
messages indicate pitch corrections in cents, with y varying between -x and +x.
"_pitchrange(0)" [default value] indicates that subsequent _pitchbend(y) messages
on the current MIDI channels take the actual MIDI value for y (range 0..16383).
⇪ _transpose(x) [Tool]
Transposes notes 'x' semitones higher in the remaining part of the sequence.
• 'x' may also be negative or decimal (down to +/- 0.01).
• Transposition is clipped to the MIDI octave range.
• Transposition is also effective on "sound-objects" whose property "Accept transposition"
is set to TRUE.
• Transpositions are cumulated over polymetric expressions.
For instance,
_transpose(-12) {_transpose(2) A3 _transpose(4) D4}
will produce the same output as:
_transpose(-10) A3 _transpose(-8) D4
• _transpose(Kx) is no longer licit.
⇪ _transposecont [Tool]
Following "_transposecont", "_transpose(x)" values are interpolated.
• Try for instance:
_transposecont _transpose(0) C4 C4 C4 C4 C4 C4 C4 C4 C4 C4 C4 _transpose(12) C4
• "_transposecont" is cancelled by "_transposefixed".
• In the current version, "_transposecont" and "_transposestep" are equivalent.
⇪ _transposestep [Tool]
See "_transposecont".
⇪ _transposefixed [Tool]
Cancels the effect of "_transposecont" or "_transposestep".
⇪ _pitchrate(x) [Current channel] [Performance control]
Sets the rate of continuous change of pitchbend to x samples per second.
⇪ _modrate(x) [Current channel] [Performance control]
Sets the rate of continuous change of modulation to x samples per second.
⇪ _pressrate(x) [Current channel] [Performance control]
Sets the rate of continuous change of channel pressure to x samples per second.
⇪ _volumerate(x) [Current channel] [Performance control]
Sets the rate of continuous change of volume to x samples per second.
⇪ _panrate(x) [Current channel] [Performance control]
Sets the rate of continuous change of panoramic controller to x samples per second.
⇪ _volume(x) [Performance control]
Controls volume on the current channel (range 0 to 127). The default controller is MIDI
controller #7 and may be changed by _volumecontrol(). Default value is 90 (as per General
MIDI specs).
• If button "Reset controllers" is checked on the "Settings" dialog, volumes on
all channels are reset to default value once an item has been played.
• Range of x is 0..127
• The argument may also be Kx. See "variable arguments". In this case it may be
controlled by a MIDI device during the performance.
⇪ _pan(x) [Performance control]
Controls panoramic on the current channel (range 0 to 127). The default controller is
MIDI controller #10 and may be changed by _pancontrol(). Default value is 64.
• If button "Reset controllers" is checked on the "Settings" dialog, panoramics on
all channels are reset to default value once an item has been played.
• Range of x is 0..127
• The argument may also be Kx. See "variable arguments". In this case it may be
controlled by a MIDI device during the performance.
⇪ _volumecont [Performance control]
Indicates that volume should change continuously between two specified values.
• See "Continuous performance control"
⇪ _panstep [Performance control]
Indicates that panoramic should change stepwise between two specified values.
⇪ _pancont [Performance control]
Indicates that panoramic should change continuously between two specified values.
• See "Continuous performance control"
⇪ _volumecontrol(x) [Current channel] [Performance control]
Informs BP3 that MIDI controller x controls the volume (on the current channel).
• Default value is 7, in agreement with "General MIDI" specs.
⇪ _pancontrol(x) [Current channel] [Performance control]
informs BP3 that MIDI controller x controls the panoramic (on the current channel).
• Default value is 10, in agreement with "General MIDI" specs.
⇪ Wait for:
When in RECording script mode, this allows you to enter a script line
"Wait for «key stroke or MIDI event»" interactively.
⇪ Execute
Execute the script displayed in the script window, if any.
⇪ Reset controllers [Settings dialog]
Resets switches, pitch benders, modulation, channel pressure, panoramic and volume
on all channels once an item has been played. This option is recommended although it may
be time consuming.
• Note that BP3 keeps track of the channels on which controllers
have been changed, so normal reset will only occur on those channels. (Consequently,
if a controller has been changed by another device than BP3, it may not be reset
properly.) However, general reset is forced when invoking "Produce items" if this
option is checked.
• From version 2.7.4 onward, only those switches that have explicitly be changed by "_switchon"
are reset.
⇪ Reset rule weights
Resets weights in grammar to original values before producing a new item.
⇪ Reset rule flags
Resets "flags" in grammar to 'zero' before producing a new item.
⇪ Non-stop improvize
Allows BP3 to produce unlimited number of items with the same grammar.
⇪ Cyclic play
Allows the same item to be repeated forever.
⇪ Use each substitution
When SUB "subgrammars" are used, allows BP3 to play items produced after each substitution.
(See "-gr.koto3" for instance)
⇪ Produce all items
Produces all items generated by grammar.
⇪ Display production
Displays all steps of the "production" in the "Trace" window.
⇪ Step-by-step produce
Displays all steps of the "production" in the "Trace" window, and allows BP3 to pause.
⇪ Step subgrammars
Allows BP3 to pause each time a "subgrammar" has been used entirely in "production".
⇪ Trace production
Displays all steps of the "production" in the "Trace" window along with decisions
taken while producing an item.
⇪ Choose candidate rule
Allows user to produce items by choosing candidate rules manually.
⇪ Display items
Allows the display of item(s) produced by the grammar. This option should be OFF if
items are very complex.
⇪ Show graphics
Displays items on the graphics window before playing them on the MIDI output.
• This option should be OFF if items are very complex.
⇪ Use time limit
Uses specified time limit, if any, to perform "computations".
⇪ Computations
Computation comprizes:
• the "production" of an item by a grammar, or the interpretation
of text selection as a musical item;
• the expansion of the item as a "polymetric expression"
• the "time-setting" of the expanded expression.
⇪ New seed (Random sequence)
Creates an arbitrary new seed that will be used for random generation. This is the
'randomize' procedure used by programmers. The new seed will be displayed and may
be reused to produce exactly the same sequence (with exactly the same grammar).
• This reseeding can be automated if the "_randomize" procedure is placed on top of
a grammar.
• Related topics: "_srand", "_randomize", "Randomize", "Reset random sequence",
"Set random seed".
⇪ Rule arrows
<-> --> and <-- are the three derive modes in grammars.
--> means that the rule may be used in "production" only
<-- means that it is to be used in analysis (parsing) only
<-> means that the rule may be used in both modes.
(This is the usual format for "true BP grammars")
⇪ true BP grammars
These grammars can be used both in "production" and in analysis (parsing).
See the reference manual. When compiling a grammar, BP3 checks whether it may be taken
as a true BP grammar.
⇪ GEN type of a Csound parameter
Indicates the Csound generator used with function tables describing variations of this
parameter. GEN07 (linear interpolation) is assumed by default. GEN08 (cubic spline)
is another option.
⇪ Reset this object
Deletes the displayed "sound-object prototype" and resets its properties to default.
• To delete a sound-object prototype permanently, first reset it and save the '-mi'
file of "sound-object prototypes". Then delete it from the "alphabet window".
⇪ Play object alone
Play the current "sound-object prototype" at the specified tempo.
⇪ Play sound-object
Play the "sound-object prototype" currently displayed in the prototypes window at the
tempo specified in that window.
⇪ Play expression:
Play item typed in the <any expression> field.
⇪ MIDI sequence
When checked, indicates that this "sound-object prototype" contains a sequence of MIDI
events that is 'active'. If unchecked, it can mean either that there is no MIDI
sequence in this "sound-object prototype" or that there is a sequence and it is
'inactive' (i.e. the prototype's MIDI events will not be played). A warning is shown
in the diagram of the prototype when it is inactive.
⇪ Sampled sound
When checked, indicates that this "sound-object prototype" contains a sound file,
or part thereof. (This feature is not yet implemented).
⇪ Csound score
When checked, indicates that this "sound-object prototype" contains a Csound score.
To create or edit a Csound score for this object, click the "Csound" button.
• Related topics: "Csound format", "Csound implementation", "Csound"
⇪ Csound scores / CSOUND file
When checked, musical items that BP3 produces
are written as Csound scores.
• Related topics: "Csound format", "Csound implementation"
⇪ (striated time)
Decide to play expression in striated or smooth time. (See "Striated time")
⇪ Striated object: Tref =...
This "sound-object prototype" is declared as 'striated', i.e. based on a
metronome setting the period of which is Tref, and may be rescaled accordingly when
performed on a different tempo. For instance, if Tref = 1000ms and metronome value
is mm = 120, this object will be rescaled at 50% its nominal duration.
⇪ Adjust duration to...
Adjust the duration of current "sound-object prototype" to the value specified
in milliseconds.
• Beware of the effects of "pre-roll" and "post-roll". Remember the formula:
Sound-object duration
= date of last event - date of first event - pre-roll + post-roll
• Both MIDI and Csound events are modified.
• Related topic: Adjust beats to...
⇪ Adjust beats to...
Adjust the duration of current "sound-object prototype" to the duration specified
in number of beats (using Tref as period).
• Beware of the effects of "pre-roll" and "post-roll". Remember the formula:
Sound-object duration
= date of last event - date of first event - pre-roll + post-roll
• Both MIDI and Csound events are modified.
• Related topic: Adjust duration to...
⇪ Adjust velocities...
Adjust velocities within specified range. Velocities 0 or velocities of NoteOff
messages are unchanged.
⇪ Append AllNotesOff
Append AllNotesOff message after the end of current "sound-object prototype".
• This is done automatically by many MIDI keyboards.
⇪ Suppress AllNotesOff
Suppress all AllNotesOff messages from the insertion point or the beginning.
⇪ Quantize NoteOn's...
Adjust dates of NoteOn messages to match specified fraction of a beat. This does not
modify NoteOff's. (Use "Expand min. durations" for that)
⇪ Expand min. durations...
Set minimum note durations to specified fraction of beat
⇪ Suppress channel pressure
Suppress all channel pressure (monophonic aftertouch) messages from the insertion point
or the beginning.
⇪ Make monodic
If two notes are overlapping, shorten the first one, and so on until object may be
performed on a single-voice patch.
⇪ Suppress pitchbend
Suppress all pitchbend messages from the insertion point or the beginning.
⇪ Suppress key pressure
Suppress all key pressure (polyphonic aftertouch) messages from the insertion
point or the beginning.
⇪ Insert silence
Create silence of specified duration and insert it at the beginning of the sound-object
prototype or at the insertion point.
• May be you actually want to set-up a positive "pre-roll"?
• Related topic: "Append silence"
⇪ Append silence
Create silence of specified duration and append it to the "sound-object prototype".
• May be you actually want to set-up a negative "post-roll"?
• Related topic: "Insert silence"
⇪ OK Rescale
This object may be compressed or dilated at will.
• Related topics: "OK Rescale", "Expand at will", "Compress at will", "Dilation ratio range"
⇪ Never rescale
This object should never be compressed nor dilated.
• Related topics: "Never rescale", "Expand at will", "Compress at will", "Dilation ratio range"
⇪ Dilation ratio
The ratio by which the duration of a "sound-object prototype" is multiplied at the
moment it is played.
• Related topics: "OK Rescale", "Never rescale", "Dilation ratio range", "Expand at will",
"Compress at will", "Send dilation ratio to controller"
⇪ Dilation ratio range:
Specify range of "dilation ratio" in which object may be rescaled.
• Related topics: "OK Rescale", "Never rescale", "Expand at will", "Compress at will"
⇪ Expand at will
This object may be dilated at will, i.e. its "dilation ratio" may become infinite.
• Related topics: "OK Rescale", "Never rescale", "Dilation ratio range", "Compress at will"
⇪ Compress at will
This object may be compressed at will, i.e. its "dilation ratio" may go down to 0.
• Related topics: "OK Rescale", "Never rescale", "Dilation ratio range", "Expand at will"
⇪ Send dilation ratio to controller:
Create a MIDI message containing "dilation ratio" and send it to the specified
controller before the first message of the object is sent. Some MIDI devices may
use this information to modify the sound generation process accordingly.
• If 'alpha' is the dilation ratio (alpha = 1 means no change in the timing), then
the value sent in this MIDI message is: 32 * log(alpha) + 64
where 'log' is a decimal logarithm.
• This controller value is clipped to the range 0..127.
⇪ Beginning
Pivot should be at the beginning of the "sound-object"'s time-span interval.
⇪ Middle
Pivot should be at the end of the "sound-object"'s time-span interval.
⇪ Set pivot
Pivot should be at specified distance from the beginning of the "sound-object"'s
time-span interval.
⇪ First NoteOn
Pivot should be on first NoteOn message.
⇪ Middle NoteOn/Off
Pivot should be in the middle of time-span interval delimited by first NoteOn and
last NoteOff messages.
⇪ Last NoteOff
Pivot should be on last NoteOff message.
⇪ Never relocate
Never relocate this "sound-object".
• Related topic: "Relocate at will"
⇪ Relocate at will
Relocate this "sound-object" at will.
• Related topic: "Never relocate"
⇪ Allow delay
Relocate this "sound-object" with delay less than specified value (in ms or fraction
of duration).
⇪ Allow forward
Relocate this "sound-object" with forward displacement less than specified value
(in milliseconds or fraction of duration).
⇪ Never cover
Never cover beginning (resp. end) of "sound-object".
• Related topic: "Cover at will"
⇪ Cover at will
Beginning (resp. end) of "sound-object" may be covered by other objects.
• Related topic: "Never cover"
⇪ Not more than
Beginning (resp. end) of object may be covered by other objects within specified
limit (in milliseconds or fraction of duration).
⇪ Never truncate
Never truncate beginning (resp. end) of object.
• Related topic: "Truncate at will"
⇪ Truncate at will
Beginning (resp. end) of object may be truncated at will.
• Related topic: "Never truncate"
⇪ Never break after this object
If checked, does not allow 'organum' on this object.
• Related topic: "Break at will"
⇪ Break at will
If checked, allows 'organum' on this object.
• Related topic: "Never break after this object"
⇪ Don't force
Do not force continuity in the beginning (resp. the end) with a neighbouring object.
• Related topics: "Force", "Allow gap"
⇪ Force
Force continuity in the beginning (resp. the end) with a neighbouring object.
• Related topics: "Don't force", "Allow gap"
⇪ Allow gap
Allow break of continuity in the beginning (resp. the end) with a neighbouring object
up to specified value (in milliseconds or fraction of duration).
• Related topics: "Don't force", "Force"
⇪ Force to current channel
Force all channel messages of this object to the channel set by context [ _chan(x) ].
⇪ Do not change channels
Never change channels of this object even if context [ _chan(x) ] demands it.
⇪ Force to channel:
Force all channel messages of this object to specified channel.
⇪ Accept transposition
If unchecked, object will ignore all "_transpose" controls.
⇪ Accept articulation changes
If unchecked, object will ignore all "_legato" and "_staccato" controls.
⇪ Accept volume changes
If unchecked, object will ignore all "_volume" controls.
⇪ Accept panoramic changes
If unchecked, object will ignore all "_pan" controls.
⇪ Accept key changes
If unchecked, object will ignore all "_keymap" and "_keyxpand" controls.
⇪ Accept velocity changes
If unchecked, velocity in this sound-object cannot be modified.
⇪ Enter and find
Enters text selection and looks for it in current window.
⇪ Tempo markers
These are numbers preceded with slashes explicitly indicating the 'speed' of a sequence
of sound-objects, i.e. the number of sound objects performed in one tick of
the metronome. In the beginning of a musical item, other numbers may indicate meter
sections. See "Section headers".
• Tempo markers are obsolete. Use "_tempo(x)" in replacement of "/x".
⇪ mm = <metronome value>
This indicates the number of ticks per minute in the "Time base".
⇪ Transpose input notes:
If checked, and if non zero value is specified, then all notes entered from the MIDI
keyboard are transposed accordingly. For instance, if the transposition value is
-3 semitones, the C5 key will be transcribed as A4.
⇪ Performance controls
To display the list of currently implemented performance controls, select
"Pick tool or performance control" in the "Edit" menu.
• Each control is documented on-line. These controls are used for
adding expressiveness to the performance (e.g. _legato, _volume, etc.) or changing
MIDI parameters (e.g. _pitchbend) that are not mapped to specific "sound-objects".
• Related topic: "Continuous performance control"
⇪ Time resolution:
The accuracy of the MIDI driver. Typically 10 ms.
⇪ Quantization:
Expected accuracy of the positions of "sound-objects". This may be set to the maximum
auditive tolerance on the perception of durations. 50ms is a good idea.
• A large quantization requires less memory space and computation time.
⇪ vel
Abbreviation for velocity.
⇪ ms
Abbreviation for milliseconds.
⇪ Speed ratio:
Each cycle of ticks may run at a speed different from the time base.
⇪ MUTE
When checked, prevents tick cycle from being heard.
⇪ _rest
See "Undetermined rests"
⇪ Set weights
Sets all rule weights in the grammar to a specified value.
⇪ Learn weights (BP2 only)
If the grammar is a "true BP grammar", it is possible to derive rule weights from a set of
examples, i.e. a set of musical items that could have been produced by the grammar.
• The result is a grammar that produces musical items very close to the ones used for the
learning process.
• Before learning weights it is advised to save the current ones. See "Save weights".
• Load the examples to the "Data" window and select them, then click "Learn weights".
• The weight of each rule will be incremented by the number of times it has been used during the
parsing of the sample set.
• At the end of parsing the option is given to add infered weights to current weights, or replace
current weights with infered weights. The first option is used when several sample sets are
needed for learning weights. The second option prompts confirmations: "Keep infered weights
in current grammar?" and "Update grammar with new weights?".
• Related topics:
"Load weights"
"Set weights"
"Save weights"
⇪ Show weights (BP2 only)
Displays the grammar with the current values of its rule weights. This is useful when the production
of items changes rule weights.
⇪ Load weights (BP2 only)
Changes weights in a grammar according to values previously saved in a '-wg' file. In many cases
a warning is issued saying that the grammar has been modified since its weights were saved,
because the weight file keeps a record of compilation time. Be careful not to load weights
obtained in a grammar with a different arrangement of rules, otherwise BP2 may crash…
• Related topics:
"Save weights"
"Set weights"
"Learn weights"
⇪ Save weights (BP2 only)
Saves the weights of rules in the current grammar to a '-wg' weight file.
• Related topics:
"Load weights"
"Set weights"
"Learn weights"
⇪ Load decisions (BP2 only)
When producing items step by step in the "Choose candidate rule" mode, it is possible to load
decisions taken previously from a decision file.
• Related topic: "Save decisions"
⇪ Save decisions (BP2 only)
When producing items step by step in the "Choose candidate rule" mode, it is possible to save
the decisions taken so far to a decision file.
• Related topic: "Load decisions"
⇪ Check variables
If a grammar is loaded and compiled, it lists the variables found by the compiler and
indicates:
• unreachable variables (that can't be generated by the grammar)
• undefined variables (that can't be rewritten by any rule in the grammar)
⇪ Pre-roll
Delay between the first event (MIDI message or Csound event) of a "sound-object" and the
beginning of its time-span interval.
• Pre-roll is null by default.
• A negative pre-roll amounts to a silence inserted before the first event of the
sound-object. This silence may for instance be 'protected' thanks to property "Never cover".
• A positive pre-roll allows some events to fall before the on-setting time
(beginning) of the sound-object. This may be useful if the sound-object contains an
initialisation sequence that should not be part of its time-span interval.
• A positive pre-roll is also the proper way of compensating a mechanical delay in the
device producing the sound-object. If for instance the event sequence in the sound-object
starts with a NoteOn and the device takes 100ms to react, then setting the pre-roll
to 100ms will displace all MIDI messages by 100ms to the past, so that their effects
coincide with the desired timings. Generally you will also set up a positive "post-roll"
to compensate the delay in setting off events.
• Remember the formula:
Sound-object duration
= date of last event - date of first event - pre-roll + post-roll
• Related topics: "Post-roll", "Insert silence"
⇪ Post-roll
Delay between the last event of a "sound-object" and the end of its time-span interval.
• Post-roll is null by default.
• A negative post-roll allows some events to fall beyond the off-setting time (end) of a
sound-object. This may be useful if the sound-object contains a final sequence of events
that should not be part of its time-span interval.
• A positive post-roll amounts to a silence appended after the last event of the
sound-object. This silence may for instance be 'protected' thanks to property "Never cover".
• A positive post-roll is also the proper way of compensating a mechanical delay in setting-off
the device producing the sound-object. If for instance the event sequence in the sound-object
ends with a NoteOff and the device takes 50ms to react, then setting the post-roll
to 50ms will append a 50ms silence after the sound-object to allow the device to finish its
job. This is generally combined with a positive "pre-roll" compensating on-setting delays.
• Remember the formula:
Sound-object duration
= date of last event - date of first event - pre-roll + post-roll
• Related topics: "Pre-roll", "Append silence"
⇪ Cyclic sound-objects
Any sound-object may contain a periodical part starting at an arbitrary point of its
time-span interval (see "Periodical after").
• BP3 handles two typical cases:
1) The sequence of events in the periodical part must be sent again
to the sound device when that part is repeated. This happens for instance
with sound-objects produced by a MIDI synthesizer.
2) Cyclic properties are defined but there is no need to repeat the sequence in
the periodical part. This happens for instance with sound-objects produced
by a MIDI sampler: the sampler expects BP3 to trigger the sample with a
NoteOn and it takes care of repetitions until a NoteOff is received.
In '-so.abc1', for instance, 'cycle1' illustrates case 1 and 'cycle2' case 2.
• Property "Discard NoteOff's except in last period" is useful with objects in case 2.
It prevents the sample from setting off as soon as the first cycle is completed.
This property is generally combined with "Don't strike again NoteOn's".
• Property "Force integer number of periods" modifies durations making sure that the
last repetition of the cyclic part is complete.
• It is a good idea to place the object's pivot at the beginning of the periodical
part. See "Set pivot".
• If a cyclic sound-object has a negative "post-roll", events falling beyond its off-setting
time are ignored.
• Beware when setting the startpoint of the periodical part: the balance between
NoteOn's and NoteOff's should be equal in the periodical part.
BP3 compensates some balance problems by avoiding two successive NoteOn's on the
same key and channel (see "Strike NoteOn's according to default") and appending
extra NoteOff's after the item when necessary, but an improper balance may result
in unwanted auditive results.
• Related topics: "OK Rescale", "Never rescale", "Dilation ratio range",
"Expand at will", "Compress at will", "Periodical after"
⇪ Periodical after
If this option is checked then the sound-object contains a periodical part starting
at a defined point of its time-span interval. The value (in milliseconds or
as a percentage of the duration) is the duration of the initial non-cyclic part.
• If the sound-object does not have the "Expand at will" property it makes no difference
to specify the initial non-cyclic part in milliseconds or as a percentage of the duration.
• The last events of a cyclic object may be discarded if its "post-roll" is set to a
negative value.
• Related topic: "Cyclic sound-objects".
⇪ No period
This sound-object has no periodical part. This is a default setting.
• Related topic: "Cyclic sound-objects".
⇪ Force integer number of periods
This property fixes acceptable durations so that the last repetition of the periodical
part is complete.
• The property is only needed for sound-objects that do not have the "Expand at will"
property, or that have specified limits for the "Dilation ratio range". However, it
does not harm to set it with resizable sound-objects.
• Related topic: "Cyclic sound-objects".
⇪ Discard NoteOff's except in last period
This property is used with cyclic sound-objects, notably the ones representing samples
on a MIDI sampler. When the object (or part of it) is repeated, then the NoteOff
encountered at the end of the first cycle may set off the sample, so that the sample
won't be heard during the following cycles.
• If the property is checked, any NoteOff will be discarded unless it appears in the
last cycle.
• With this property it is recommended to check "Don't strike again NoteOn's", so that
no unwanted NoteOff's are produced when NoteOn's are found in the repeated cycle.
• Related topic: "Cyclic sound-objects".
⇪ Strike again NoteOn's
If a NoteOn must be sent while the same key of the same channel is already active
(because a NoteOn has already been sent) then BP3 will first send a NoteOff to
deactivate the key.
This is the default mode in BP3 (see "Strike NoteOn's according to default").
• Some MIDI sound devices may hang if two successive NoteOn's are sent to the same
key and the same channel. BP3 keeps track of key on/off status to make sure this
never happens.
• Related topic: "Don't strike again NoteOn's"
⇪ Don't strike again NoteOn's
If a NoteOn must be sent while the same key of the same channel is already active
(because a NoteOn has already been sent) then BP3 will ignore it.
• This is not BP3's default mode: see "Strike NoteOn's according to default"
• Related topics: "Strike again NoteOn's", "Discard NoteOff's except in last period"
⇪ Strike NoteOn's according to default
If a NoteOn must be sent while the same key of the same channel is already active
(because a NoteOn has already been sent) then BP3 will behave as per its default
setting.
• BP3's default setting is the behaviour defined as "Strike again NoteOn's".
• Related topic: "Don't strike again NoteOn's"
⇪ % of duration
The specified value is a percentage of the sound-object's duration, so the actual
value will vary according to its "dilation ratio".
⇪ Csound implementation
• Csound is a 100% software environment for the design and transformation of digitized
sounds. It runs on most platforms, including MacOS 9 & X, Linux, and Windows.
Csound is "free software" (open source) distributed under the GNU LGPL license.
• To download Csound, follow instructions on the https://bolprocessor.org/check-bp3/ page
• BP3 produces Csound scores in the same way it produces MIDI files or real-time MIDI:
the "CSOUND file" option may be selected in the "Output" menu and is saved with
the options of the current project or data.
• Once the option has been selected you may produce a Csound score for each musical item
produced by a grammar or played from its text representation (a BP3 "score"). Items
may be played on real-time MIDI, saved to Csound scores, to MIDI files, or any
combination of these.
• If the musical item contains simple notes or sound-objects defined as streams of MIDI
messages, BP3 converts the stream to a sequence of Csound events, using the
specifications of Csound instruments defined in a "Csound instrument file". This file
can be created and edited in the "Csound instruments" dialog accessible from the
"Devices" menu. Csound instrument specifications should contain data that is
consistent with the "orchestra" file that will be invoked by Csound when compiling
the score produced by BP3.
• If no "Csound instrument file" is loaded, BP3 uses a default instrument which has only
the start/end timing arguments and accepts pitch in the "octave point pitch-class"
representation. It is more clever to design a Cound orchestra with instruments
accepting parameters like pitchbend, pressure, modulation etc., which BP3 handles
in a smart way, using a "vector" representation of continuous parameter changes.
• Sound-object protoypes may also contain Csound scores. In this case, BP3 creates a
score of the musical item arranging these individual scores after changing their
timings and arguments according to the musical item and specifications of Csound
instruments. BP3 may therefore produce Csound scores using only Csound events and
Csound instrument specifications as an input, thereby bypassing current limitations
of MIDI.
• The mapping between Csound argument values (the ones found in the Csound score) and
MIDI / BP3 ranges is defined automatically once the user has supplied three typical
pairs of values. BP3 performs linear or quadratic interpolation, plus logarithmic
mapping if requested to do so.
• In addition, BP3 handles "Performance parameters" with arbitrary names the values
of which may be taken as arguments by Csound instruments.
• Related topic: "Csound format"
⇪ octave point pitch-class
In this representation, pitch is represented as a decimal number in which the integer
part is the octave number and the decimal part is the pitch class.
• For example, the following mapping is used:
C4 = 8.00 D4 = 8.02 E4 = 8.04 F4 = 8.05 G4 = 8.07
A4 = 8.09 B4 = 8.11
⇪ octave point decimal
In this representation, pitch is represented as a decimal number in which the integer
part is the octave number and the decimal part is the fraction of the octave.
• For example, the following mapping is used:
C4 = 8.00 D4 = 8.17 E4 = 8.33 F4 = 8.42 G4 = 8.58
A4 = 8.75 B4 = 8.92
⇪ cps (Hz)
In this representation, pitch is represented in cycles per second (Hertz).
• For example, the following mapping is used:
C5 = 523.25 D5 = 587.33 E5 = 659.26 F5 = 698.46 G5 = 783.99
A5 = 880.00 B5 = 987.77
• These values depend on the settings of the diapason in the "Tuning dialog".
⇪ Pitchbend arguments:
Boxes contain the indexes of arguments sending pitchbend information to this
Csound instrument.
• The left box is the argument containing the pitchbend value at the start date of
any event related to this instrument.
• The middle box (optional) is the argument containing the pitchbend value at the clip
date of any event related to this instrument.
• The rightmost box (optional) is the argument which may refer to a function table
for continuous variations.
• If this instrument does not use pitchbend leave boxes empty.
⇪ Pitchbender range (cents) +/-
This box contains the range (in cents) of the pitchbend used in MIDI format, which
may have been specified in the data or grammar with "_pitchrange(x)".
• This information may be needed by BP3 for a correct remapping of pitchbend values
from MIDI to Csound.
⇪ Volume arguments:
Boxes contain the indexes of arguments sending volume information to this
Csound instrument.
• The left box is the argument containing the volume value at the start date of
any event related to this instrument.
• The middle box (optional) is the argument containing the volume value at the clip
date of any event related to this instrument.
• The rightmost box (optional) is the argument which may refer to a function table
for continuous variations.
• If this instrument does not use volume leave boxes empty.
⇪ Pressure arguments:
Boxes contain the indexes of arguments sending channel pressure information to this
Csound instrument.
• The left box is the argument containing the pressure value at the start date of
any event related to this instrument.
• The middle box (optional) is the argument containing the pressure value at the clip
date of any event related to this instrument.
• The rightmost box (optional) is the argument which may refer to a function table
for continuous variations.
• If this instrument does not use pressure leave boxes empty.
⇪ Modulation arguments:
Boxes contain the indexes of arguments sending modulation information to this
Csound instrument.
• The left box is the argument containing the modulation value at the start date of
any event related to this instrument.
• The middle box (optional) is the argument containing the modulation value at the clip
date of any event related to this instrument.
• The rightmost box (optional) is the argument which may refer to a function table
for continuous variations.
• If this instrument does not use modulation leave boxes empty.
⇪ Panoramic arguments:
Boxes contain the indexes of arguments sending panoramic information to this
Csound instrument.
• The left box is the argument containing the panoramic value at the start date of
any event related to this instrument.
• The middle box (optional) is the argument containing the panoramic value at the clip
date of any event related to this instrument.
• The rightmost box (optional) is the argument which may refer to a function table
for continuous variations.
• If this instrument does not use panoramic leave boxes empty.
⇪ Attack velocity argument:
This box contains the index of the argument of this Csound instrument which should
contain the NoteOn velocity information.
• Leave the box empty if this instrument does not need the information.
⇪ Release velocity argument:
This box contains the index of the argument of this Csound instrument which should
contain the NoteOff velocity information.
• Leave the box empty if this instrument does not need the information.
⇪ Dilation ratio argument:
This box contains the index of the argument of this Csound instrument which should
contain the "dilation ratio" information.
• Leave the box empty if this instrument does not need the information.
⇪ Start argument
This is the index of the argument used in a Csound event to pass on the value of this
parameter, or the initial value in case it varies continuously.
(See "Continuous performance control")
• Related topics: "Parameter name", "End argument", "Table argument"
⇪ End argument
This is the index of the argument used in a Csound event to pass on the final value of
this parameter in case it varies continuously.
(See "Continuous performance control")
• The box may remain empty if the parameter never varies continuously or the Csound
instrument is not designed for continuous variation of this parameter.
• Related topics: "Parameter name", "Start argument", "Table argument"
⇪ Table argument
This is the index of the argument used in a Csound event to pass on the index of
a function table when the parameter varies continuously.
(See "Continuous performance control")
• The box may remain empty if the parameter never varies continuously or the Csound
instrument is not designed for continuous variation of this parameter.
• Related topics: "Parameter name", "Start argument", "End argument"
⇪ Argument boxes
• The left box contains the index of the Csound instrument argument taking the initial
value of this control.
• The middle box is only used for "continuous performance control". It contains the
index of the argument taking the final value of this control.
• The rightmost box contains the index of the argument taking the reference of the
function table that BP3 creates for defining complex parameter variations.
(See "Continuous performance control")
⇪ Continuous performance control
• A few MIDI parameters such as pitchbend, modulation, volume, channel pressure and
panoramic may be controlled continuously at a given sampling rate. For example,
a portamento may be produced by the following BP3 score:
_pitchcont _pitchrate(20) _pitchbend(6000) A4 B4 _pitchbend(9000)
in which BP3 will insert 20 pitchbend messages per second.
• Similarly, arbitrary parameters may be handled with effect only on the Csound
output. (See "Performance parameter"). For instance,
_cont(blurb) _value(blurb,154.2) A4 B4 _value(blurb,-21) C4
• The default sampling rate is 50 messages per second.
• Csound events do not allow the insertion of real-time messages. Therefore it is
necessary to supply the start and end values of the argument which will be
interpolated by the procedure associated with the Csound instrument. For instance,
let the start value of pitchbend be sent as argument 5 and the end value as
argument 6. The score produced by BP3 using the preceding item reads:
i1 0 1 8.09 6000 7500
i1 1 1 8.11 7500 9000
("8.09" and "8.11" are the respective pitch values of A4 and B4.)
• Another option with Csound is to allow BP3 to create function tables to control
the values. An argument of the instrument should be reserved to passing on the
table reference.
• Related topic: "Step performance control"
⇪ Step performance control
• By default, all MIDI controls are modified only when explicit values are assigned
to them by the BP3 score. For instance, the following score assigns different
modulation values to notes B4, C5 and D5:
_modstep A4 _mod(2000) B4 C5 _mod(9000) D5
Replacing "_modstep" (which is optional here) with "_modcont" would
cause continuous changes of modulation at the rate of 50 messages per second.
• In this example it is advisable to check "Reset controllers" since the final value
(9000) is not the same as the initial one (0).
• Related topic: "Continuous performance control"
⇪ Store all items to same file
If checked, all musical items are stored to the same MIDI or Csound score file.
⇪ Change name
Click this button to close the current MIDI or Csound score file and create a new one.
⇪ MIDI file format
BP3 supports three MIDI file formats: types 0, 1 and 2. Here are tips for choosing
an output format:
• If the file will contain a single musical item, or a sequence of items produced by a
grammar in the "Improvize" mode, any format is OK. Keep in mind, however, that
format 2 may be rejected by single-track MIDI programs.
• In the current version, BP3 saves each item to a single track. Types 0 and 1 may
therefore be considered equivalent.
• If the file will contain several independent musical items (each of which might
have a different tempo or time signature), then type 2 must be used.
• BP3 imports files type 0, 1 or 2. With format 1 it superimposes the tracks even if
they have different time signatures. With format 2, however, an error message
will be displayed if the file contains several items.
⇪ Convert to Csound
Creates a Csound score attached to this "sound-object prototype" on the basis of events
contained in its MIDI stream.
• Beware that the result depends on the "Csound instruments" defined in the currently
loaded '-cs' "Csound instrument file". If some MIDI controls have no
mapping to Csound arguments they will simply be ignored.
• If no "Csound instruments" file has been loaded, a default, minimum instrument
description is used.
• Related topic: "Csound instrument file"
⇪ Import MIDI file
Reads a MIDI file and uses its content as a MIDI stream for this
sound-object prototype.
⇪ Change instrument file
Define or change a '-cs' "Csound instrument file" attached to these "sound-object prototypes".
⇪ Csound instrument file
• This file contains a description of "Csound instruments" used to convert sound-objects
to Csound scores, or to produce Csound scores from musical items containing
"sound-objects" and/or "simple notes".
• The file is accessed in the "Csound instruments" dialog of the "Output" menu.
• This description must be consistent with the Csound orchestra file used to
play items produced by BP3. This consistency is not checked by the present
version.
• "Sound-object prototypes" may contain a Csound score that must relate to these
Csound instruments.
• Related topics: "Csound implementation", "Csound format"
⇪ Period (cyclic object) / strike mode
Displays the dialog for setting these parameters.
• Related topics:
"Cyclic sound-objects"
"Strike again NoteOn's"
"Don't strike again NoteOn's"
⇪ Continuity / pre-postroll
Displays the dialog for setting these parameters.
• Related topics:
"Don't force", "Force", "Allow gap"
"Post-roll", "Pre-roll"
⇪ Cover / truncate / break tempo
Displays the dialog for setting these parameters.
• Related topics:
"Cover at will", "Never cover"
"Truncate at will", "Never truncate"
"Break at will", "Never break after this object"
⇪ Csound file format
Csound scores are text files saved as Unicode UTF8.
⇪ ADDval
If checked, values of this parameter are combined additively.
• The formula is the following:
If 'p0' is the parameter value found in the Csound score of a "sound-object", and 'x'
the assigned value, the parameter value in the resulting score will be:
p1 = p0 + x - default
('default' is specified in the field "Default value".)
• Related topics: "MULTval", "Default value"
⇪ MULTval
If checked, values of this parameter are combined multiplicatively.
• The formula is the following:
If 'p0' is the parameter value found in the Csound score of a "sound-object", and 'x'
the assigned value, the parameter value in the resulting score will be:
p1 = p0 * (x / default)
('default' is specified in the field "Default value".)
• Related topics: "ADDval", "Default value"
⇪ Default value
The default value of this Csound parameter. It is used when "sound-objects" contain
incomplete Csound score lines, and in the combination of parameters (see related
topics).
• Related topics: "MULTval", "ADDval"
⇪ DATA:
Below this header, anything written is ignored by the grammar compiler.
• "DATA:" is quivalent to "COMMENT:"
⇪ COMMENT:
Below this header, anything written is ignored by the grammar compiler.
• "COMMENT:" is equivalent to "DATA:"
⇪ Grammar procedures
A set of tools modifying the application of rules in a grammar.
⇪ Serial music with BP3
• Version 2.8.1 of BP2 introduced a few tools facilitating the design of musical structures
following principles of serial music. However, these tools are applied to structures
that may be more complex than simple sequences of sound-objects: "polymetric expressions",
polyrhythmic phrases using the "period notation", tree structures constructed with
"variables" in a grammar, metastructures containing "wild cards", etc.
• The current serial tools are:
"_retro", "_rndseq", "_rotate", "_ordseq", "_keymap", "_keyxpand".
⇪ _retro [Tool]
A tool for "serial music".
This "tool" reverts the order of "sound-objects", "variables", "wild cards" and "time patterns"
in the remaining part of a sequence.
• Examples
a b _retro c d e will become a b e d c
a b _retro {c d e,f g} will become a b {e d c,g f} ["polymetric expression"]
a b _retro {t1 t2 t3,f g} will become a b {t3 t2 t1,g f} ["time patterns"]
_retro {a b c • d e • f g} will become {g f • e d • c b a} ["period notation"]
a b _retro c d e _retro f g will become a b f g e d c ["_retro" cancels itself]
• Check the preceding examples in ‘-gr.trySerial’
• Related topics: "_rndseq", "_ordseq", "_rotate".
⇪ _rndseq [Tool]
A tool for "serial music".
This "tool" shuffles the order of "sound-objects", "variables", "wild cards" and "time patterns"
in the remaining part of a sequence.
• Don't confuse with "_randomize" which reseeds the random number generator.
• Examples [each example actually produces several combinations]
a b _rndseq c d e could become a b c e d
a b _rndseq {c d e,f g} could become a b {d e c,g f} ["polymetric expression"]
a b _rndseq {t1 t2 t3,f g} could become a b {t3 t1 t2,g f} ["time patterns"]
_rndseq {a b c • d e • f g} could become {b d f • c g • e a} ["period notation"]
• Check the preceding examples in ‘-gr.trySerial’
• Related topics: "_retro", "_ordseq", "_rotate", "_srand", "_randomize".
⇪ _rotate(x) [Tool]
A tool for "serial music".
Rotates a sequence of "sound-objects" or "simple notes" (left shift of 'x' units).
• For instance,
_rotate(3) A4 B4 C4 D4 E4 F4 G4 yields D4 E4 F4 G4 A4 B4 C4
• Rotation is applied recursively and cumulated additively on polymetric structures.
(See '-gr.tryRotate' for a typical example)
• Range of x is -128..127
• The argument may also be Kx. See "variable arguments". In this case it may be
controlled by a MIDI device during the performance.
⇪ _ordseq [Tool]
A tool for "serial music".
This "tool" prevents the remaining part of a sequence from being modified by "_rndseq",
"_rotate" or "_retro".
• Related topics: "_rndseq", "_retro", "_rotate"
⇪ _keymap(p1,q1,p2,q2) [Performance control]
A performance control for "serial music".
In the following sequence, this "performance control" modifies pitches in range (p1,p2)
according to a linear mapping in which q1 is the image of p1 and q2 the image of p2.
• The tool makes changes on "simple notes" and on "sound-objects" in which the property
"Accept key changes" has been set to true.
• Unlike "_keyxpand", changes do not occur during the production of a "grammar",
but at "performance time".
• p1,q1,p2,q2 may be written as integers (key numbers) in range 0..127, or "simple notes"
using the current "note convention", e.g.: _keymap(C3,G2,D6,F6).
• See '-gr.tryKeyMap' for typical examples.
• Related topic: "_keyxpand"
⇪ _keyxpand(p,x) [Tool]
A tool for "serial music".
• In the following sequence, this "tool" multiplies by x melodic intervals relative to the
centre note p. For instance,
_keyxpand(C4,-2) B3 C4 D4 E4 yields D4 C4 G#3 E3.
• Unlike "_keymap", this tool changes "simple notes" during the production of a "grammar".
• x is an integer or a floating point number.
• Just like "_retro", "_rndseq" and "_rotate", _keyxpand is applied recursively to the
fields of a polymetric expression. Values are cumulated multiplicatively if the centre
note is the same. For instance,
_keyxpand(C4,-2) B3 C4 {_keyxpand(C4,-1) D4 E4} yields D4 C4 {E4 G#3},
i.e. the same as _keyxpand(C4,-2) B3 C4 _keyxpand(C4,2) {D4 E4}.
• _keyxpand also makes changes on "simple notes" and on "sound-objects" in which the property
"Accept key changes" has been set to true.
• See '-gr.tryKeyXpand' for typical examples.
• Related topic: "_keymap"
⇪ _tempo(x) [Tool]
Multiplies the tempo by 'x'
• The argument may be a floating-point number or an integer ratio.
Thus, _tempo(4/3) and _tempo(0.35) are valid expressions.
• In "polymetric expressions" tempo values are multiplied.
For instance, in
A4 B4 _tempo(2) C5 D5 {_tempo(1.5) E5 F5}
"E5 F5" is performed at tempo 3 = 1.5 * 2.
• The above example shows that speed change is relative.
Thus, '_tempo(2)' is not the strict equivalent of '/2' (the obsolete "tempo marker"
notation) although it should replace it in most cases. "Tempo markers" are kept only
for compatibility with old BP3 projects.
⇪ Variable arguments
Some "performance controls", "tools", and rule weights in a grammar, can be given arguments
notated K1, K2, ... Kx.
• These variables may be assigned fixed values (Kx = n) that are used in the grammar.
• In some cases, Kx can be set by an external MIDI device during the performance.
(See "Interactive mode").
⇪ MIDI fade-out
• If set to a value 'x' greater than zero, fade-out will append silences of duration 'x' after
each track of a MIDI file, during which volume decreases stepwise on all channels.
This compensates for the harshness of terminating the playback of MIDI files.
• Note that this fade-out is performed during a silence and does not affect notes played
during the performance. Use "_volume" and "_volumecont" to change volume during
the performance.
⇪ TIMEPATTERNS
A set of time ratios used to fix relative durations (only in the context of smooth time)
⇪ END OF BP3 help