annotate CollidoscopeApp/include/AudioEngine.h @ 2:dd889fff8423

added some comments

#pragma once

#include <array>

#include "cinder/audio/Context.h"
#include "cinder/audio/ChannelRouterNode.h"
#include "cinder/audio/MonitorNode.h"
#include "cinder/audio/FilterNode.h"
#include "BufferToWaveRecorderNode.h"
#include "PGranularNode.h"
#include "RingBufferPack.h"

#include "Messages.h"
#include "Config.h"


/**
 * Audio engine of the application. It uses the Cinder library to process audio in input and output. 
 * The audio engine manages both waves. All methods have a waveIndx parameter to address a specific wave.
 */ 
class AudioEngine
{
public:

    AudioEngine();

    ~AudioEngine();

    // no copies
    AudioEngine( const AudioEngine &copy ) = delete;
    AudioEngine & operator=(const AudioEngine &copy) = delete;

    /**
    * Set up of the audio engine. 
    */
    void setup( const Config& Config );

    size_t getSampleRate();

    void record( size_t index );

    void loopOn( size_t waveIdx );

    void loopOff( size_t waveIdx );

    void noteOn( size_t waveIdx, int note );

    void noteOff( size_t waveIdx, int note );

    /**
    * Returns the number of elements available to read in the wave ring buffer.
    * The wave ring buffer is used to pass the size of the wave chunks from the audio thread to the graphic thread, 
    * when a new wave is recorded.
    */ 
    size_t getRecordWaveAvailable( size_t index );
    /**
    * Called from the graphic thread. Reads count elements from the wave ring buffer into \a buffer.
    * The wave ring buffer is used to pass the size of the wave chunks from the audio thread to the graphic thread, 
    * when a new wave is recorded.
    *
    */
    bool readRecordWave( size_t waveIdx, RecordWaveMsg* buffer, size_t count );

    void setSelectionSize( size_t waveIdx, size_t size );

    void setSelectionStart( size_t waveIdx, size_t start );

    void setGrainDurationCoeff( size_t waveIdx, double coeff );

    void setFilterCutoff( size_t waveIdx, double cutoff );

    void checkCursorTriggers( size_t waveIdx, std::vector<CursorTriggerMsg>& cursorTriggers );

    /**
     * Returns a const reference to the audio output buffer. This is the buffer that is sent off to the audio interface at each audio cycle. 
     * It is used in the graphic thread to draw the oscilloscope.
     */
    const ci::audio::Buffer& getAudioOutputBuffer( size_t waveIdx ) const;


private:

    // nodes for mic input 
    std::array< ci::audio::ChannelRouterNodeRef, NUM_WAVES > mInputRouterNodes;
    // nodes for recording audio input into buffer. Also sends chunks information through 
    // non-blocking queue 
    std::array< BufferToWaveRecorderNodeRef, NUM_WAVES > mBufferRecorderNodes;
    // pgranulars for loop synths 
    std::array< PGranularNodeRef, NUM_WAVES > mPGranularNodes;


    std::array< ci::audio::ChannelRouterNodeRef, NUM_WAVES > mOutputRouterNodes;
    // nodes to get the audio buffer scoped in the oscilloscope 
    std::array< ci::audio::MonitorNodeRef, NUM_WAVES > mOutputMonitorNodes;
    // nodes for lowpass filtering
    std::array< cinder::audio::FilterLowPassNodeRef, NUM_WAVES> mLowPassFilterNodes;

    std::array< std::unique_ptr< RingBufferPack<CursorTriggerMsg> >, NUM_WAVES > mCursorTriggerRingBufferPacks;

};