jm.music.rt

Class RTLine

java.lang.Object

jm.music.rt.RTLine

All Implemented Interfaces:

AudioChainListener

Direct Known Subclasses:

AudioRTLine, RTPhrase

public abstract class RTLine
extends java.lang.Object
implements AudioChainListener

This class frovides a framework for real time audio playback. It renders a Part using the provided instrument(s). If there are more than one instrument it is assumed they are simply multiple instances of the one instrument. These are used to play notes that overlap in the score or as a result of effects such as delays or reverb. There is an assumption that all instruments have the same sample rate number of channels.

Field Summary

Fields

Modifier and Type	Field and Description
protected boolean	clear if clear is true the threads wait call will be skipped
protected Instrument[]	inst The instrument associated with this real time line

Constructor Summary

Constructors

Constructor and Description
RTLine(Instrument[] inst) The RTLine constructor is primarily responsible for initialising its associated instrument and the instruments audio chain.

Method Summary

Methods

Modifier and Type	Method and Description
void	controlChange(float[] buffer, int returned, boolean finished) controlChange is called by RTLine's instrument everytime it completes filling its current buffer.
void	externalAction(java.lang.Object obj, int actionNumber) External action is called by RTMixer whenever an external event is sent to trigger a real time audio event.
int	getChannels() Return the current number of channels, based on the channels of the instruments.
Instrument[]	getInstrument() Returns the instrument associated with this RTLine
abstract Note	getNextNote() Override this method to set the next method to be called.
int	getNumLines() Return the number of lines (note polyphony for this RTLine
int	getSampleRate() Return the current samplerate, based on the sample rate of the instruments.
void	instNote(Instrument inst, long samplesProcessed) This method is called from Instrument and in return calls that instrument's renderNote method.
void	pause()
void	setBufferSize(int buf) Specify the buffer size for each instrument.
void	setTempo(double tempo) sets the tempo of this RTLine
void	start(RTMixer rta) start this RTLine's instrument call for the setting of the first note
void	stop()
void	unPause()

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

inst

protected Instrument[] inst

The instrument associated with this real time line

clear

protected boolean clear

if clear is true the threads wait call will be skipped

Constructor Detail

RTLine

public RTLine(Instrument[] inst)

The RTLine constructor is primarily responsible for initialising its associated instrument and the instruments audio chain.

Method Detail

getInstrument

public Instrument[] getInstrument()

Returns the instrument associated with this RTLine

Returns:

Instrument the instrument associated with this RTLine

getNumLines

public int getNumLines()

Return the number of lines (note polyphony for this RTLine

setTempo

public void setTempo(double tempo)

sets the tempo of this RTLine

setBufferSize

public void setBufferSize(int buf)

Specify the buffer size for each instrument. Called by RTMixer.

getSampleRate

public int getSampleRate()

Return the current samplerate, based on the sample rate of the instruments. All instrument sample rates in real time audio must be the same.

getChannels

public int getChannels()

Return the current number of channels, based on the channels of the instruments. All instruments in real time audio must have the same number of channels.

externalAction

public void externalAction(java.lang.Object obj,
                  int actionNumber)

External action is called by RTMixer whenever an external event is sent to trigger a real time audio event. The event will commonly be triggered by a GUI widget such as a button or slider.

Parameters:

obj - and undetermined Object which will need to be cast locally to whatever type is expected.

actionNumber - is an serial index value for the source of the event.

controlChange

public void controlChange(float[] buffer,
                 int returned,
                 boolean finished)

controlChange is called by RTLine's instrument everytime it completes filling its current buffer. The regularity at which controlChange is called is what determines the control rate. The control rate is used therefore to set the buffer sizes of the instrument sample buffers.

Specified by:

controlChange in interface AudioChainListener

Parameters:

buffer - a buffer of samples passed from an instrument

returned - the number of samples in the buffer

finished - this boolean indicates whether the instrument has finished processing its current note.

instNote

public void instNote(Instrument inst,
            long samplesProcessed)

This method is called from Instrument and in return calls that instrument's renderNote method. When this method returns, the instruments iterateChain method is called and the note is processed. This method is responsible for either fetching a "playable" note from the getNextNote() method or else for inserting a rest of an appropriate amount of time.

start

public void start(RTMixer rta)

start this RTLine's instrument call for the setting of the first note

pause

public void pause()

unPause

public void unPause()

stop

public void stop()

getNextNote

public abstract Note getNextNote()

Override this method to set the next method to be called.