paulxstretch/Source/ps3_BufferingAudioSource.h

117 lines
4.8 KiB
C++

/*
Copyright (C) 2017 Xenakios
This program is free software; you can redistribute it and/or modify
it under the terms of version 3 of the GNU General Public License
as published by the Free Software Foundation.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License (version 3) for more details.
www.gnu.org/licenses
*/
#pragma once
#include "../JuceLibraryCode/JuceHeader.h"
//==============================================================================
/**
An AudioSource which takes another source as input, and buffers it using a thread.
Create this as a wrapper around another thread, and it will read-ahead with
a background thread to smooth out playback. You can either create one of these
directly, or use it indirectly using an AudioTransportSource.
@see PositionableAudioSource, AudioTransportSource
@tags{Audio}
*/
class JUCE_API MyBufferingAudioSource : public PositionableAudioSource,
private TimeSliceClient
{
public:
//==============================================================================
/** Creates a BufferingAudioSource.
@param source the input source to read from
@param backgroundThread a background thread that will be used for the
background read-ahead. This object must not be deleted
until after any BufferingAudioSources that are using it
have been deleted!
@param deleteSourceWhenDeleted if true, then the input source object will
be deleted when this object is deleted
@param numberOfSamplesToBuffer the size of buffer to use for reading ahead
@param numberOfChannels the number of channels that will be played
@param prefillBufferOnPrepareToPlay if true, then calling prepareToPlay on this object will
block until the buffer has been filled
*/
MyBufferingAudioSource(PositionableAudioSource* source,
TimeSliceThread& backgroundThread,
bool deleteSourceWhenDeleted,
int numberOfSamplesToBuffer,
int numberOfChannels = 2,
bool prefillBufferOnPrepareToPlay = true);
/** Destructor.
The input source may be deleted depending on whether the deleteSourceWhenDeleted
flag was set in the constructor.
*/
~MyBufferingAudioSource();
//==============================================================================
/** Implementation of the AudioSource method. */
void prepareToPlay (int samplesPerBlockExpected, double sampleRate) override;
/** Implementation of the AudioSource method. */
void releaseResources() override;
/** Implementation of the AudioSource method. */
void getNextAudioBlock (const AudioSourceChannelInfo&) override;
//==============================================================================
/** Implements the PositionableAudioSource method. */
void setNextReadPosition (int64 newPosition) override;
/** Implements the PositionableAudioSource method. */
int64 getNextReadPosition() const override;
/** Implements the PositionableAudioSource method. */
int64 getTotalLength() const override { return source->getTotalLength(); }
/** Implements the PositionableAudioSource method. */
bool isLooping() const override { return source->isLooping(); }
/** A useful function to block until the next the buffer info can be filled.
This is useful for offline rendering.
*/
bool waitForNextAudioBlockReady (const AudioSourceChannelInfo& info, const uint32 timeout);
double getPercentReady();
int getNumberOfChannels() { return numberOfChannels; }
private:
//==============================================================================
OptionalScopedPointer<PositionableAudioSource> source;
TimeSliceThread& backgroundThread;
int numberOfSamplesToBuffer, numberOfChannels;
AudioBuffer<float> buffer;
CriticalSection bufferStartPosLock;
WaitableEvent bufferReadyEvent;
std::atomic<int64> bufferValidStart { 0 }, bufferValidEnd { 0 }, nextPlayPos { 0 };
double sampleRate = 0;
bool wasSourceLooping = false, isPrepared = false, prefillBuffer;
bool readNextBufferChunk();
void readBufferSection (int64 start, int length, int bufferOffset);
int useTimeSlice() override;
JUCE_DECLARE_NON_COPYABLE_WITH_LEAK_DETECTOR (MyBufferingAudioSource)
};