openshot-audio  0.1.2
Public Member Functions | Friends | List of all members
AudioProcessorParameter Class Referenceabstract

#include <juce_AudioProcessorParameter.h>

Public Member Functions

 AudioProcessorParameter () noexcept
 
virtual ~AudioProcessorParameter ()
 
virtual float getValue () const =0
 
virtual void setValue (float newValue)=0
 
void setValueNotifyingHost (float newValue)
 
void beginChangeGesture ()
 
void endChangeGesture ()
 
virtual float getDefaultValue () const =0
 
virtual String getName (int maximumStringLength) const =0
 
virtual String getLabel () const =0
 
virtual int getNumSteps () const
 
virtual String getText (float value, int) const
 
virtual float getValueForText (const String &text) const =0
 
virtual bool isOrientationInverted () const
 
virtual bool isAutomatable () const
 
virtual bool isMetaParameter () const
 
int getParameterIndex () const noexcept
 

Friends

class AudioProcessor
 

Detailed Description

An abstract base class for parameter objects that can be added to an AudioProcessor.

See also
AudioProcessor::addParameter

Constructor & Destructor Documentation

AudioProcessorParameter::AudioProcessorParameter ( )
noexcept
AudioProcessorParameter::~AudioProcessorParameter ( )
virtual

Destructor.

Member Function Documentation

void AudioProcessorParameter::beginChangeGesture ( )

Sends a signal to the host to tell it that the user is about to start changing this parameter. This allows the host to know when a parameter is actively being held by the user, and it may use this information to help it record automation. If you call this, it must be matched by a later call to endChangeGesture().

void AudioProcessorParameter::endChangeGesture ( )

Tells the host that the user has finished changing this parameter. This allows the host to know when a parameter is actively being held by the user, and it may use this information to help it record automation. A call to this method must follow a call to beginChangeGesture().

virtual float AudioProcessorParameter::getDefaultValue ( ) const
pure virtual

This should return the default value for this parameter.

virtual String AudioProcessorParameter::getLabel ( ) const
pure virtual

Some parameters may be able to return a label string for their units. For example "Hz" or "%".

virtual String AudioProcessorParameter::getName ( int  maximumStringLength) const
pure virtual

Returns the name to display for this parameter, which should be made to fit within the given string length.

int AudioProcessorParameter::getNumSteps ( ) const
virtual

Returns the number of discrete interval steps that this parameter's range should be quantised into.

If you want a continuous range of values, don't override this method, and allow the default implementation to return AudioProcessor::getDefaultNumParameterSteps(). If your parameter is boolean, then you may want to make this return 2. The value that is returned may or may not be used, depending on the host.

int AudioProcessorParameter::getParameterIndex ( ) const
inlinenoexcept

Returns the index of this parameter in its parent processor's parameter list.

String AudioProcessorParameter::getText ( float  value,
int   
) const
virtual

Returns a textual version of the supplied parameter value. The default implementation just returns the floating point value as a string, but this could do anything you need for a custom type of value.

virtual float AudioProcessorParameter::getValue ( ) const
pure virtual

Called by the host to find out the value of this parameter.

Hosts will expect the value returned to be between 0 and 1.0.

This could be called quite frequently, so try to make your code efficient. It's also likely to be called by non-UI threads, so the code in here should be thread-aware.

virtual float AudioProcessorParameter::getValueForText ( const String text) const
pure virtual

Should parse a string and return the appropriate value for it.

bool AudioProcessorParameter::isAutomatable ( ) const
virtual

Returns true if the host can automate this parameter. By default, this returns true.

bool AudioProcessorParameter::isMetaParameter ( ) const
virtual

Should return true if this parameter is a "meta" parameter. A meta-parameter is a parameter that changes other params. It is used by some hosts (e.g. AudioUnit hosts). By default this returns false.

bool AudioProcessorParameter::isOrientationInverted ( ) const
virtual

This can be overridden to tell the host that this parameter operates in the reverse direction. (Not all plugin formats or hosts will actually use this information).

virtual void AudioProcessorParameter::setValue ( float  newValue)
pure virtual

The host will call this method to change the value of one of the filter's parameters.

The host may call this at any time, including during the audio processing callback, so the filter has to process this very fast and avoid blocking.

If you want to set the value of a parameter internally, e.g. from your editor component, then don't call this directly - instead, use the setValueNotifyingHost() method, which will also send a message to the host telling it about the change. If the message isn't sent, the host won't be able to automate your parameters properly.

The value passed will be between 0 and 1.0.

void AudioProcessorParameter::setValueNotifyingHost ( float  newValue)

Your filter can call this when it needs to change one of its parameters.

This could happen when the editor or some other internal operation changes a parameter. This method will call the setValue() method to change the value, and will then send a message to the host telling it about the change.

Note that to make sure the host correctly handles automation, you should call the beginChangeGesture() and endChangeGesture() methods to tell the host when the user has started and stopped changing the parameter.

Friends And Related Function Documentation

friend class AudioProcessor
friend

The documentation for this class was generated from the following files: