#include <ScrubState.h>

Inheritance diagram for ScrubbingPlaybackPolicy:

Collaboration diagram for ScrubbingPlaybackPolicy:

Public Member Functions
	ScrubbingPlaybackPolicy (const ScrubbingOptions &)

	~ScrubbingPlaybackPolicy () override

void	Initialize (PlaybackSchedule &schedule, double rate) override
	Called before starting an audio stream. More...

void	Finalize (PlaybackSchedule &schedule) override
	Called after stopping of an audio stream or an unsuccessful start. More...

Mixer::WarpOptions	MixerWarpOptions (PlaybackSchedule &schedule) override
	Options to use when constructing mixers for each playback track. More...

BufferTimes	SuggestedBufferTimes (PlaybackSchedule &schedule) override
	Provide hints for construction of playback RingBuffer objects. More...

bool	AllowSeek (PlaybackSchedule &) override
	Whether repositioning commands are allowed during playback. More...

std::chrono::milliseconds	SleepInterval (PlaybackSchedule &) override
	How long to wait between calls to AudioIO::SequenceBufferExchange. More...

bool	Done (PlaybackSchedule &schedule, unsigned long) override
	Returns true if schedule.GetSequenceTime() has reached the end of playback. More...

PlaybackSlice	GetPlaybackSlice (PlaybackSchedule &schedule, size_t available) override
	Choose length of one fetch of samples from tracks in a call to AudioIO::FillPlayBuffers. More...

std::pair< double, double >	AdvancedTrackTime (PlaybackSchedule &schedule, double trackTime, size_t nSamples) override
	Compute a new point in a track's timeline from an old point and a real duration. More...

bool	RepositionPlayback (PlaybackSchedule &schedule, const Mixers &playbackMixers, size_t frames, size_t available) override
	AudioIO::FillPlayBuffers calls this to update its cursors into tracks for changes of position or speed. More...

Public Member Functions inherited from PlaybackPolicy
virtual	~PlaybackPolicy ()=0

virtual void	Initialize (PlaybackSchedule &schedule, double rate)
	Called before starting an audio stream. More...

virtual void	Finalize (PlaybackSchedule &schedule)
	Called after stopping of an audio stream or an unsuccessful start. More...

virtual Mixer::WarpOptions	MixerWarpOptions (PlaybackSchedule &schedule)
	Options to use when constructing mixers for each playback track. More...

virtual BufferTimes	SuggestedBufferTimes (PlaybackSchedule &schedule)
	Provide hints for construction of playback RingBuffer objects. More...

virtual bool	AllowSeek (PlaybackSchedule &schedule)
	Whether repositioning commands are allowed during playback. More...

virtual bool	Done (PlaybackSchedule &schedule, unsigned long outputFrames)
	Returns true if schedule.GetSequenceTime() has reached the end of playback. More...

virtual double	OffsetSequenceTime (PlaybackSchedule &schedule, double offset)
	Called when the play head needs to jump a certain distance. More...

virtual std::chrono::milliseconds	SleepInterval (PlaybackSchedule &schedule)
	How long to wait between calls to AudioIO::SequenceBufferExchange. More...

virtual PlaybackSlice	GetPlaybackSlice (PlaybackSchedule &schedule, size_t available)
	Choose length of one fetch of samples from tracks in a call to AudioIO::FillPlayBuffers. More...

virtual std::pair< double, double >	AdvancedTrackTime (PlaybackSchedule &schedule, double trackTime, size_t nSamples)
	Compute a new point in a track's timeline from an old point and a real duration. More...

virtual bool	RepositionPlayback (PlaybackSchedule &schedule, const Mixers &playbackMixers, size_t frames, size_t available)
	AudioIO::FillPlayBuffers calls this to update its cursors into tracks for changes of position or speed. More...

virtual bool	Looping (const PlaybackSchedule &schedule) const

Private Attributes
sampleCount	mScrubDuration { 0 }

sampleCount	mStartSample { 0 }

sampleCount	mEndSample { 0 }

double	mOldEndTime { 0 }

double	mNewStartTime { 0 }

double	mScrubSpeed { 0 }

bool	mSilentScrub { false }

bool	mReplenish { false }

size_t	mUntilDiscontinuity { 0 }

const ScrubbingOptions	mOptions

Additional Inherited Members
Public Types inherited from PlaybackPolicy
using	Duration = std::chrono::duration< double >

using	Mixers = std::vector< std::unique_ptr< Mixer > >

Protected Attributes inherited from PlaybackPolicy
double	mRate = 0

Detailed Description

Definition at line 48 of file ScrubState.h.

Constructor & Destructor Documentation

◆ ScrubbingPlaybackPolicy()

ScrubbingPlaybackPolicy::ScrubbingPlaybackPolicy ( const ScrubbingOptions & options )

explicit

Definition at line 293 of file ScrubState.cpp.

295 : mOptions{ options }

296{}

ScrubbingPlaybackPolicy::mOptions

const ScrubbingOptions mOptions

Definition: ScrubState.h:88

◆ ~ScrubbingPlaybackPolicy()

ScrubbingPlaybackPolicy::~ScrubbingPlaybackPolicy ( )

overridedefault

Member Function Documentation

◆ AdvancedTrackTime()

std::pair< double, double > ScrubbingPlaybackPolicy::AdvancedTrackTime	(	PlaybackSchedule &	schedule,
		double	trackTime,
		size_t	nSamples
	)

overridevirtual

Compute a new point in a track's timeline from an old point and a real duration.

Needed because playback might be at non-unit speed.

Called one or more times between GetPlaybackSlice and RepositionPlayback, until the sum of the nSamples values equals the most recent playback slice (including any trailing silence).

Returns: a pair, which indicates a discontinuous jump when its members are not equal, or specially the end of playback when the second member is infinite

Reimplemented from PlaybackPolicy.

Definition at line 402 of file ScrubState.cpp.

{
   auto realDuration = nSamples / mRate;
   auto result = trackTime + realDuration * mScrubSpeed;
   bool discontinuity = nSamples > 0 &&
      mUntilDiscontinuity > 0 &&
      0 == (mUntilDiscontinuity -= std::min(mUntilDiscontinuity, nSamples));
   if (discontinuity)
      return { mOldEndTime, mNewStartTime };
   else
      return { result, result };
}

References min(), mNewStartTime, mOldEndTime, PlaybackPolicy::mRate, mScrubSpeed, and mUntilDiscontinuity.

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◆ AllowSeek()

bool ScrubbingPlaybackPolicy::AllowSeek ( PlaybackSchedule & schedule )

overridevirtual

Whether repositioning commands are allowed during playback.

by the main thread

Reimplemented from PlaybackPolicy.

Definition at line 346 of file ScrubState.cpp.

{
   // While scrubbing, ignore seek requests
   return false;
}

◆ Done()

bool ScrubbingPlaybackPolicy::Done	(	PlaybackSchedule &	schedule,
		unsigned long	outputFrames
	)

overridevirtual

Returns true if schedule.GetSequenceTime() has reached the end of playback.

Parameters

outputFrames how many playback frames were taken from RingBuffers

Reimplemented from PlaybackPolicy.

Definition at line 352 of file ScrubState.cpp.

{
   return false;
}

◆ Finalize()

void ScrubbingPlaybackPolicy::Finalize ( PlaybackSchedule & schedule )

overridevirtual

Called after stopping of an audio stream or an unsuccessful start.

Reimplemented from PlaybackPolicy.

Definition at line 312 of file ScrubState.cpp.

{
   ScrubQueue::Instance.Stop();
}

◆ GetPlaybackSlice()

PlaybackSlice ScrubbingPlaybackPolicy::GetPlaybackSlice	(	PlaybackSchedule &	schedule,
		size_t	available
	)

overridevirtual

Choose length of one fetch of samples from tracks in a call to AudioIO::FillPlayBuffers.

Parameters

available upper bound for the length of the fetch

Reimplemented from PlaybackPolicy.

Definition at line 364 of file ScrubState.cpp.

{
   if (mReplenish)
      return { available, 0, 0 };
 
   auto gAudioIO = AudioIO::Get();
 
   // How many samples to produce for each channel.
   auto frames = available;
   auto toProduce = frames;
 
   // scrubbing and play-at-speed are not limited by the real time
   // and length accumulators
   toProduce =
      frames = limitSampleBufferSize(frames, mScrubDuration);
 
   if (mSilentScrub)
      toProduce = 0;
 
   mScrubDuration -= frames;
   wxASSERT(mScrubDuration >= 0);
 
   mUntilDiscontinuity = 0;
   if (mScrubDuration <= 0) {
      mReplenish = true;
      auto oldEndSample = mEndSample;
      mOldEndTime = oldEndSample.as_long_long() / mRate;
      ScrubQueue::Instance.Get(
         mStartSample, mEndSample, available, mScrubDuration);
      mNewStartTime = mStartSample.as_long_long() / mRate;
      if(mScrubDuration >= 0 && oldEndSample != mStartSample)
         mUntilDiscontinuity = frames;
   }
 
   return { available, frames, toProduce };
}

References sampleCount::as_long_long(), AudioIO::Get(), limitSampleBufferSize(), mEndSample, mNewStartTime, mOldEndTime, PlaybackPolicy::mRate, mReplenish, mScrubDuration, mSilentScrub, mStartSample, and mUntilDiscontinuity.

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◆ Initialize()

void ScrubbingPlaybackPolicy::Initialize	(	PlaybackSchedule &	schedule,
		double	rate
	)

overridevirtual

Called before starting an audio stream.

Reimplemented from PlaybackPolicy.

Definition at line 300 of file ScrubState.cpp.

{
   PlaybackPolicy::Initialize(schedule, rate);
   mScrubDuration = mStartSample = mEndSample = 0;
   mOldEndTime = mNewStartTime = 0;
   mScrubSpeed = 0;
   mSilentScrub = mReplenish = false;
   mUntilDiscontinuity = 0;
   ScrubQueue::Instance.Init( schedule.mT0, rate, mOptions );
}

References PlaybackPolicy::Initialize(), mEndSample, mNewStartTime, mOldEndTime, mOptions, mReplenish, mScrubDuration, mScrubSpeed, mSilentScrub, mStartSample, PlaybackSchedule::mT0, and mUntilDiscontinuity.

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◆ MixerWarpOptions()

Mixer::WarpOptions ScrubbingPlaybackPolicy::MixerWarpOptions ( PlaybackSchedule & schedule )

overridevirtual

Options to use when constructing mixers for each playback track.

Reimplemented from PlaybackPolicy.

Definition at line 317 of file ScrubState.cpp.

{
   return Mixer::WarpOptions{
      ScrubbingOptions::MinAllowedScrubSpeed(),
      ScrubbingOptions::MaxAllowedScrubSpeed() };
}

References ScrubbingOptions::MaxAllowedScrubSpeed(), and ScrubbingOptions::MinAllowedScrubSpeed().

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◆ RepositionPlayback()

bool ScrubbingPlaybackPolicy::RepositionPlayback	(	PlaybackSchedule &	schedule,
		const Mixers &	playbackMixers,
		size_t	frames,
		size_t	available
	)

overridevirtual

AudioIO::FillPlayBuffers calls this to update its cursors into tracks for changes of position or speed.

Returns: if true, AudioIO::FillPlayBuffers stops producing samples even if space remains

Parameters

frames	how many samples were just now buffered for play
available	how many more samples may be buffered

Reimplemented from PlaybackPolicy.

Definition at line 416 of file ScrubState.cpp.

{
   auto gAudioIO = AudioIO::Get();
 
   if (available > 0 && mReplenish)
   {
      mReplenish = false;
      if (mScrubDuration < 0)
      {
         // Can't play anything
         // Stop even if we don't fill up available
         mScrubDuration = 0;
 
         // Force stop of filling of buffers
         return true;
      }
      else
      {
         mSilentScrub = (mEndSample == mStartSample);
         double startTime, endTime;
         startTime = mStartSample.as_double() / mRate;
         endTime = mEndSample.as_double() / mRate;
         auto diff = (mEndSample - mStartSample).as_long_long();
         if (mScrubDuration == 0)
            mScrubSpeed = 0;
         else
            mScrubSpeed =
               double(diff) / mScrubDuration.as_double();
         if (!mSilentScrub)
         {
            for (auto &pMixer : playbackMixers) {
               if (mOptions.isKeyboardScrubbing)
                  pMixer->SetSpeedForKeyboardScrubbing(mScrubSpeed, startTime);
               else
                  pMixer->SetTimesAndSpeed(
                     startTime, endTime, fabs( mScrubSpeed ));
            }
         }
      }
   }
 
   return false;
}

References sampleCount::as_double(), AudioIO::Get(), ScrubbingOptions::isKeyboardScrubbing, mEndSample, mOptions, PlaybackPolicy::mRate, mReplenish, mScrubDuration, mScrubSpeed, mSilentScrub, and mStartSample.

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◆ SleepInterval()

std::chrono::milliseconds ScrubbingPlaybackPolicy::SleepInterval ( PlaybackSchedule & schedule )

overridevirtual

How long to wait between calls to AudioIO::SequenceBufferExchange.

by the main thread

Reimplemented from PlaybackPolicy.

Definition at line 359 of file ScrubState.cpp.

{
   return ScrubPollInterval;
}

References ScrubPollInterval.

◆ SuggestedBufferTimes()

PlaybackPolicy::BufferTimes ScrubbingPlaybackPolicy::SuggestedBufferTimes ( PlaybackSchedule & schedule )

overridevirtual

Provide hints for construction of playback RingBuffer objects.

Reimplemented from PlaybackPolicy.

Definition at line 325 of file ScrubState.cpp.

{
   using namespace std::chrono;
   return {
      // For useful scrubbing, we can't run too far ahead without checking
      // mouse input, so make fillings more and shorter.
      // Specify a very short minimum batch for non-seek scrubbing, to allow
      // more frequent polling of the mouse
      mOptions.delay,
 
      // Specify enough playback RingBuffer latency so we can refill
      // once every seek stutter without falling behind the demand.
      // (Scrub might switch in and out of seeking with left mouse
      // presses in the ruler)
      2 * mOptions.minStutterTime,
 
      // Same as for default policy
      10.0s
   };
}

References ScrubbingOptions::delay, ScrubbingOptions::minStutterTime, and mOptions.

Member Data Documentation

◆ mEndSample

sampleCount ScrubbingPlaybackPolicy::mEndSample { 0 }

private

Definition at line 81 of file ScrubState.h.

Referenced by GetPlaybackSlice(), Initialize(), and RepositionPlayback().

◆ mNewStartTime

double ScrubbingPlaybackPolicy::mNewStartTime { 0 }

private

Definition at line 82 of file ScrubState.h.

Referenced by AdvancedTrackTime(), GetPlaybackSlice(), and Initialize().

◆ mOldEndTime

double ScrubbingPlaybackPolicy::mOldEndTime { 0 }

private

Definition at line 82 of file ScrubState.h.

Referenced by AdvancedTrackTime(), GetPlaybackSlice(), and Initialize().

◆ mOptions

const ScrubbingOptions ScrubbingPlaybackPolicy::mOptions

private

Definition at line 88 of file ScrubState.h.

Referenced by Initialize(), RepositionPlayback(), and SuggestedBufferTimes().

◆ mReplenish

bool ScrubbingPlaybackPolicy::mReplenish { false }

private

Definition at line 85 of file ScrubState.h.

Referenced by GetPlaybackSlice(), Initialize(), and RepositionPlayback().

◆ mScrubDuration

sampleCount ScrubbingPlaybackPolicy::mScrubDuration { 0 }

private

Definition at line 81 of file ScrubState.h.

Referenced by GetPlaybackSlice(), Initialize(), and RepositionPlayback().

◆ mScrubSpeed

double ScrubbingPlaybackPolicy::mScrubSpeed { 0 }

private

Definition at line 83 of file ScrubState.h.

Referenced by AdvancedTrackTime(), Initialize(), and RepositionPlayback().

◆ mSilentScrub

bool ScrubbingPlaybackPolicy::mSilentScrub { false }

private

Definition at line 84 of file ScrubState.h.

Referenced by GetPlaybackSlice(), Initialize(), and RepositionPlayback().

◆ mStartSample

sampleCount ScrubbingPlaybackPolicy::mStartSample { 0 }

private

Definition at line 81 of file ScrubState.h.

Referenced by GetPlaybackSlice(), Initialize(), and RepositionPlayback().

◆ mUntilDiscontinuity

size_t ScrubbingPlaybackPolicy::mUntilDiscontinuity { 0 }

private

Definition at line 86 of file ScrubState.h.

Referenced by AdvancedTrackTime(), GetPlaybackSlice(), and Initialize().

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

Public Member Functions

Private Attributes

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ ScrubbingPlaybackPolicy()

◆ ~ScrubbingPlaybackPolicy()

Member Function Documentation

◆ AdvancedTrackTime()

◆ AllowSeek()

by the main thread

◆ Done()

◆ Finalize()

◆ GetPlaybackSlice()

◆ Initialize()

◆ MixerWarpOptions()

◆ RepositionPlayback()

◆ SleepInterval()

by the main thread

◆ SuggestedBufferTimes()

Member Data Documentation

◆ mEndSample

◆ mNewStartTime

◆ mOldEndTime

◆ mOptions

◆ mReplenish

◆ mScrubDuration

◆ mScrubSpeed

◆ mSilentScrub

◆ mStartSample

◆ mUntilDiscontinuity