SequencerOutputThread Class Reference

Sequence player auxiliary class. More...

#include <playthread.h>

Inheritance diagram for SequencerOutputThread:

Public Slots
void	start (QThread::Priority priority=InheritPriority)
	Starts the playback thread. More...

Signals
void	playbackFinished ()
	Signal emitted when the sequence play-back has finished.
void	playbackStopped ()
	Signal emitted when the play-back has stopped.

Public Member Functions
	SequencerOutputThread (MidiClient *seq, int portId)
	Constructor. More...
virtual void	run () override
	Thread process loop.
virtual unsigned int	getInitialPosition ()
	Gets the initial position in ticks of the sequence. More...
virtual unsigned int	getEchoResolution ()
	Gets the echo event resolution in ticks. More...
virtual bool	hasNext ()=0
	Check if there is one more event in the sequence. More...
virtual SequencerEvent *	nextEvent ()=0
	Gets the next event in the sequence. More...
virtual void	stop ()
	Stops playing the current sequence. More...

Protected Member Functions
virtual void	sendEchoEvent (int tick)
	Sends an echo event, with the same PortId as sender and destination. More...
virtual void	sendSongEvent (SequencerEvent *ev)
	Sends a SequencerEvent. More...
virtual void	drainOutput ()
	Flush the ALSA output buffer.
virtual void	syncOutput ()
	Waits until the ALSA output queue is empty (all the events have been played.)
virtual bool	stopRequested ()
	Checks if stop has been requested. More...

Protected Attributes
MidiClient *	m_MidiClient
	MidiClient instance pointer.
MidiQueue *	m_Queue
	MidiQueue instance pointer.
int	m_PortId
	MidiPort numeric identifier.
bool	m_Stopped
	Stopped status.
int	m_QueueId
	MidiQueue numeric identifier.
int	m_npfds
	Number of pollfd pointers.
pollfd *	m_pfds
	Array of pollfd pointers.
QReadWriteLock	m_mutex
	Mutex object used for synchronization.

Detailed Description

Sequence player auxiliary class.

This class is used to implement an asynchronous sequence player using ALSA sequencer scheduling

Examples: guiplayer.cpp and playsmf.cpp

Definition at line 58 of file playthread.h.

Constructor & Destructor Documentation

SequencerOutputThread()

SequencerOutputThread	(	MidiClient *	seq,
		int	portId
	)

Constructor.

Parameters

seq	Existing MidiClient object pointer
portId	Numeric input/output port identifier

Definition at line 67 of file playthread.cpp.

References MidiClient::getQueue(), SequencerOutputThread::m_MidiClient, SequencerOutputThread::m_Queue, and SequencerOutputThread::m_QueueId.

Member Function Documentation

getEchoResolution()

virtual unsigned int getEchoResolution ( )

inlinevirtual

Gets the echo event resolution in ticks.

This is the time between echo events interleaved with the MIDI sequence. The default value zero means that no echo events are sent at all.

Returns

Echo resolution (ticks)

Definition at line 77 of file playthread.h.

Referenced by SequencerOutputThread::run().

getInitialPosition()

virtual unsigned int getInitialPosition ( )

inlinevirtual

Gets the initial position in ticks of the sequence.

The default value zero means starting from the beginning.

Returns

Initial position (ticks)

Definition at line 70 of file playthread.h.

Referenced by SequencerOutputThread::run().

hasNext()

virtual bool hasNext ( )

pure virtual

Check if there is one more event in the sequence.

This is a pure virtual method that must be overridden in the derived class.

Returns

True if the sequence has another event.

Referenced by SequencerOutputThread::run().

nextEvent()

virtual SequencerEvent * nextEvent ( )

pure virtual

Gets the next event in the sequence.

This is a pure virtual function that must be overridden in the derived class.

Returns

Pointer to the next SequencerEvent to be played.

Referenced by SequencerOutputThread::run().

sendEchoEvent()

void sendEchoEvent ( int  tick )

protectedvirtual

Sends an echo event, with the same PortId as sender and destination.

Parameters

tick	Event schedule time in ticks.

Definition at line 114 of file playthread.cpp.

References MidiClient::getClientId(), SequencerOutputThread::m_MidiClient, SequencerOutputThread::m_PortId, SequencerOutputThread::m_QueueId, SequencerEvent::scheduleTick(), SequencerOutputThread::sendSongEvent(), SequencerEvent::setDestination(), SequencerEvent::setSource(), and SequencerOutputThread::stopRequested().

Referenced by SequencerOutputThread::run().

sendSongEvent()

void sendSongEvent ( SequencerEvent *  ev )

protectedvirtual

Sends a SequencerEvent.

Parameters

ev	SequencerEvent object pointer

Definition at line 130 of file playthread.cpp.

References MidiClient::getHandle(), SequencerEvent::getHandle(), SequencerOutputThread::m_MidiClient, SequencerOutputThread::m_npfds, SequencerOutputThread::m_pfds, and SequencerOutputThread::stopRequested().

Referenced by SequencerOutputThread::run(), and SequencerOutputThread::sendEchoEvent().

start

void start ( QThread::Priority  priority = InheritPriority )

slot

Starts the playback thread.

Parameters

priority

Thread priority, default is InheritPriority

Definition at line 219 of file playthread.cpp.

References SequencerOutputThread::m_mutex, and SequencerOutputThread::m_Stopped.

stop()

void stop ( )

virtual

Stops playing the current sequence.

Stops the playback task.

Definition at line 99 of file playthread.cpp.

References SequencerOutputThread::m_mutex, and SequencerOutputThread::m_Stopped.

stopRequested()

bool stopRequested ( )

protectedvirtual

Checks if stop has been requested.

Returns

True if stop has been requested

Since

0.2.0

Definition at line 89 of file playthread.cpp.

References SequencerOutputThread::m_mutex, and SequencerOutputThread::m_Stopped.

Referenced by SequencerOutputThread::drainOutput(), SequencerOutputThread::run(), SequencerOutputThread::sendEchoEvent(), SequencerOutputThread::sendSongEvent(), and SequencerOutputThread::syncOutput().

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

• playthread.h
• playthread.cpp