net.beadsproject.beads.ugens

Class CrossoverFilter

java.lang.Object

net.beadsproject.beads.core.Bead

net.beadsproject.beads.core.UGen

net.beadsproject.beads.ugens.CrossoverFilter

All Implemented Interfaces:

DataBeadReceiver

public class CrossoverFilter
extends UGen
implements DataBeadReceiver

A multi-channel 4th-order Linkwitz-Riley crossover filter. For each input channel, the filter outputs both a low-pass and a high-pass channel. If the filter has two inputs, for example, then it will output four channels:

• 0: Low-pass of input 0
• 1: High-pass of input 0
• 2: Low-pass of input 1
• 3: High-pass of input 1

A key feature of Linkwitz-Riley filters is that the low- and high-pass bands added together produce a flat frequency response, making them particularly useful as crossover filters. A 4th-order version is equivalent to cascading two identical 2nd-order Butterworth filters.

Version:

0.9.5

Author:

Benito Crawford

Nested Class Summary

Nested classes/interfaces inherited from class net.beadsproject.beads.core.UGen

UGen.OutputInitializationRegime, UGen.OutputPauseRegime

Field Summary

Fields

Modifier and Type	Field and Description
static float	SQRT2

Fields inherited from class net.beadsproject.beads.core.UGen

bufferSize, bufIn, bufOut, context, ins, outputInitializationRegime, outputPauseRegime, outs

Constructor Summary

Constructors

Constructor and Description
CrossoverFilter(AudioContext context) Constructor for a one-channel crossover filter, initialized with a cutoff frequency of 800Hz.
CrossoverFilter(AudioContext context, int channels) Constructor for a crossover filter with the specified number of channels, initialized with a cutoff frequency of 800Hz.
CrossoverFilter(AudioContext context, int channels, float freq) Constructor for a crossover filter with the specified number of channels, set at the specified frequency.

Method Summary

Modifier and Type	Method and Description
void	calculateBuffer() Called by the signal chain to update this UGen's ouput data.
CrossoverFilter	drawFromHighOutput(int channel, UGen target, int targetInputIndex)
CrossoverFilter	drawFromHighOutput(UGen target)
CrossoverFilter	drawFromLowOutput(int channel, UGen target, int targetInputIndex)
CrossoverFilter	drawFromLowOutput(UGen target)
int	getChannels() Gets the number of channels.
float	getFreq() Deprecated. Use getFrequency().
float	getFrequency() Gets the current cutoff frequency.
UGen	getFrequencyUGen() Gets the UGen controlling the cutoff frequency, if there is one.
UGen	getFreqUGen() Deprecated. Use getFrequencyUGen().
void	messageReceived(Bead message) Responds to an incoming message.
void	reset() Resets the filter in case it "explodes".
DataBeadReceiver	sendData(DataBead db) Sets the crossover frequency with a DataBead.
CrossoverFilter	setFreq(float freq) Deprecated. Use setFrequency(float).
CrossoverFilter	setFreq(UGen freqUGen) Deprecated. Use setFrequency(UGen).
CrossoverFilter	setFrequency(float freq) Sets the cutoff frequency to a static float value.
CrossoverFilter	setFrequency(UGen freqUGen) Sets a UGen to control the cutoff frequency.

Methods inherited from class net.beadsproject.beads.core.UGen

addDependent, addInput, addInput, clearDependents, clearInputConnections, containsInput, crossfadeInput, getConnectedInputs, getContext, getEnvelopes, getIns, getNumberOfConnectedUGens, getNumberOfDependents, getOutBuffer, getOuts, getTimeTakenLastUpdate, getValue, getValue, getValueDouble, getValueDouble, initializeOuts, isTimerMode, isUpdated, noInputs, pause, printInBuffers, printInputList, printOutBuffers, removeAllConnections, removeConnection, removeDependent, setOutsToPause, setTimerMode, setValue, update, zeroIns, zeroOuts

Methods inherited from class net.beadsproject.beads.core.Bead

getKillListener, getName, isDeleted, isPaused, kill, message, setKillListener, setName, start, toString

Methods inherited from class java.lang.Object

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

Field Detail

SQRT2

public static final float SQRT2

Constructor Detail

CrossoverFilter

public CrossoverFilter(AudioContext context)

Constructor for a one-channel crossover filter, initialized with a cutoff frequency of 800Hz.

Parameters:

context - The audio context.

CrossoverFilter

public CrossoverFilter(AudioContext context,
                       int channels)

Constructor for a crossover filter with the specified number of channels, initialized with a cutoff frequency of 800Hz.

Parameters:

context - The audio context.

channels - The number of channels.

CrossoverFilter

public CrossoverFilter(AudioContext context,
                       int channels,
                       float freq)

Constructor for a crossover filter with the specified number of channels, set at the specified frequency.

Parameters:

context - The audio context.

channels - The number of channels.

freq - The initial cutoff frequency.

Method Detail

calculateBuffer

public void calculateBuffer()

Description copied from class: UGen

Called by the signal chain to update this UGen's ouput data. Subclassses of UGen should implement the UGen's DSP perform routine here. In general this involves grabbing data from UGen.bufIn and putting data into UGen.bufOut in some way. UGen.bufIn and UGen.bufOut are 2D arrays of floats of the form float[numChannels][bufferSize]. The length of the buffers is given by UGen.bufferSize, and the number of channels of the input and output buffers are given by UGen.ins and UGen.outs respectively.

Specified by:

calculateBuffer in class UGen

reset

public void reset()

Resets the filter in case it "explodes".

getFrequency

public float getFrequency()

Gets the current cutoff frequency.

Returns:

The cutoff frequency.

setFrequency

public CrossoverFilter setFrequency(float freq)

Sets the cutoff frequency to a static float value.

Parameters:

freq - The cutoff frequency in Hertz.

Returns:

This filter instance.

setFrequency

public CrossoverFilter setFrequency(UGen freqUGen)

Sets a UGen to control the cutoff frequency. Note that the frequency is only updated every frame, not every sample.

Parameters:

freqUGen - The UGen to control the cutoff frequency.

Returns:

This filter instance.

getFrequencyUGen

public UGen getFrequencyUGen()

Gets the UGen controlling the cutoff frequency, if there is one.

Returns:

The UGen controlling the cutoff frequency.

getFreq

@Deprecated
public float getFreq()

Deprecated. Use getFrequency().

Gets the current cutoff frequency.

Returns:

The cutoff frequency.

setFreq

@Deprecated
public CrossoverFilter setFreq(float freq)

Deprecated. Use setFrequency(float).

Sets the cutoff frequency to a static float value.

Parameters:

freq - The cutoff frequency in Hertz.

Returns:

This filter instance.

setFreq

@Deprecated
public CrossoverFilter setFreq(UGen freqUGen)

Deprecated. Use setFrequency(UGen).

Sets a UGen to control the cutoff frequency. Note that the frequency is only updated every frame, not every sample.

Parameters:

freqUGen - The UGen to control the cutoff frequency.

Returns:

This filter instance.

getFreqUGen

@Deprecated
public UGen getFreqUGen()

Deprecated. Use getFrequencyUGen().

Gets the UGen controlling the cutoff frequency, if there is one.

Returns:

The UGen controlling the cutoff frequency.

getChannels

public int getChannels()

Gets the number of channels.

Returns:

The number of channels.

sendData

public DataBeadReceiver sendData(DataBead db)

Sets the crossover frequency with a DataBead. If the value of the property "frequency" is either a UGen or can be interpreted as a float, the cutoff frequency will be set appropriately.

Specified by:

sendData in interface DataBeadReceiver

Parameters:

db - The DataBead message.

Returns:

Typically, the object instance: this.

messageReceived

public void messageReceived(Bead message)

Description copied from class: Bead

Responds to an incoming message. Subclasses can override this in order to handle incoming messages. Typically a Bead would send a message to another Bead with itself as the arugment.

Overrides:

messageReceived in class Bead

Parameters:

message - the message

drawFromLowOutput

public CrossoverFilter drawFromLowOutput(UGen target)

drawFromLowOutput

public CrossoverFilter drawFromLowOutput(int channel,
                                         UGen target,
                                         int targetInputIndex)

drawFromHighOutput

public CrossoverFilter drawFromHighOutput(UGen target)

drawFromHighOutput

public CrossoverFilter drawFromHighOutput(int channel,
                                          UGen target,
                                          int targetInputIndex)