AudioPlayHead Class Reference

A subclass of AudioPlayHead can supply information about the position and status of a moving play head during audio playback. More...

#include <juce_AudioPlayHead.h>

Classes
struct	CurrentPositionInfo
	This type is deprecated; prefer PositionInfo instead. More...
class	FrameRate
	More descriptive frame rate type. More...
struct	LoopPoints
	Holds the begin and end points of a looped region. More...
class	PositionInfo
	Describes the time at the start of the current audio callback. More...
struct	TimeSignature
	Describes a musical time signature. More...

Public Types
enum	FrameRateType {   fps23976 = 0 , fps24 = 1 , fps25 = 2 , fps2997 = 3 ,   fps30 = 4 , fps2997drop = 5 , fps30drop = 6 , fps60 = 7 ,   fps60drop = 8 , fpsUnknown = 99 }
	Frame rate types. More...

Public Member Functions
virtual	~AudioPlayHead ()=default
bool	getCurrentPosition (CurrentPositionInfo &result)
	Deprecated, use getPosition() instead.
virtual Optional< PositionInfo >	getPosition () const =0
	Fetches details about the transport's position at the start of the current processing block.
virtual bool	canControlTransport ()
	Returns true if this object can control the transport.
virtual void	transportPlay (bool shouldStartPlaying)
	Starts or stops the audio.
virtual void	transportRecord (bool shouldStartRecording)
	Starts or stops recording the audio.
virtual void	transportRewind ()
	Rewinds the audio.

Protected Member Functions
	AudioPlayHead ()=default

Detailed Description

A subclass of AudioPlayHead can supply information about the position and status of a moving play head during audio playback.

One of these can be supplied to an AudioProcessor object so that it can find out about the position of the audio that it is rendering.

See also

AudioProcessor::setPlayHead, AudioProcessor::getPlayHead

Member Enumeration Documentation

FrameRateType

enum AudioPlayHead::FrameRateType

Frame rate types.

Enumerator
fps23976
fps24
fps25
fps2997
fps30
fps2997drop
fps30drop
fps60
fps60drop
fpsUnknown

Constructor & Destructor Documentation

AudioPlayHead()

AudioPlayHead::AudioPlayHead ( )

protecteddefault

~AudioPlayHead()

virtual AudioPlayHead::~AudioPlayHead ( )

virtualdefault

Member Function Documentation

getCurrentPosition()

bool AudioPlayHead::getCurrentPosition

(

CurrentPositionInfo &

result

)

Deprecated, use getPosition() instead.

Fills-in the given structure with details about the transport's position at the start of the current processing block. If this method returns false then the current play head position is not available and the given structure will be undefined.

You can ONLY call this from your processBlock() method! Calling it at other times will produce undefined behaviour, as the host may not have any context in which a time would make sense, and some hosts will almost certainly have multithreading issues if it's not called on the audio thread.

References AudioPlayHead::CurrentPositionInfo::bpm, AudioPlayHead::CurrentPositionInfo::editOriginTime, AudioPlayHead::CurrentPositionInfo::frameRate, AudioPlayHead::CurrentPositionInfo::isLooping, AudioPlayHead::CurrentPositionInfo::isPlaying, AudioPlayHead::CurrentPositionInfo::isRecording, AudioPlayHead::CurrentPositionInfo::ppqLoopEnd, AudioPlayHead::CurrentPositionInfo::ppqLoopStart, AudioPlayHead::CurrentPositionInfo::ppqPosition, AudioPlayHead::CurrentPositionInfo::ppqPositionOfLastBarStart, AudioPlayHead::CurrentPositionInfo::resetToDefault(), AudioPlayHead::CurrentPositionInfo::timeInSamples, AudioPlayHead::CurrentPositionInfo::timeInSeconds, AudioPlayHead::CurrentPositionInfo::timeSigDenominator, and AudioPlayHead::CurrentPositionInfo::timeSigNumerator.

getPosition()

virtual Optional< PositionInfo > AudioPlayHead::getPosition ( ) const

pure virtual

Fetches details about the transport's position at the start of the current processing block.

If this method returns nullopt then the current play head position is not available.

A non-null return value just indicates that the host was able to provide some* relevant timing information. Individual PositionInfo getters may still return nullopt.

You can ONLY call this from your processBlock() method! Calling it at other times will produce undefined behaviour, as the host may not have any context in which a time would make sense, and some hosts will almost certainly have multithreading issues if it's not called on the audio thread.

canControlTransport()

virtual bool AudioPlayHead::canControlTransport ( )

virtual

Returns true if this object can control the transport.

transportPlay()

virtual void AudioPlayHead::transportPlay ( bool shouldStartPlaying )

virtual

Starts or stops the audio.

transportRecord()

virtual void AudioPlayHead::transportRecord ( bool shouldStartRecording )

virtual

Starts or stops recording the audio.

transportRewind()

virtual void AudioPlayHead::transportRewind ( )

virtual

Rewinds the audio.

---

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

• juce_AudioPlayHead.h