Collidoscope

#include "PGranularNode.h"

#include "cinder/audio/Context.h"

#include "cinder/Rand.h"

// generate random numbers from 0 to max 

// it's passed to PGranular to randomize the phase offset at grain creation 

struct RandomGenerator

{

    RandomGenerator( size_t max ) : mMax( max )

    {}

    size_t operator()() const {

        return ci::Rand::randUint( mMax );

    }

    size_t mMax;

};

// FIXME maybe use only one random gen 

PGranularNode::PGranularNode( ci::audio::Buffer *grainBuffer, CursorTriggerMsgRingBuffer &triggerRingBuffer ) :

    Node( Format().channels( 1 ) ),

    mGrainBuffer(grainBuffer),

    mSelectionStart( 0 ),

    mSelectionSize( 0 ),

    mGrainDurationCoeff( 1 ),

    mTriggerRingBuffer( triggerRingBuffer ),

    mNoteMsgRingBufferPack( 128 )

{

    for ( int i = 0; i < kMaxVoices; i++ ){

        mMidiNotes[i] = kNoMidiNote;

    }

}

PGranularNode::~PGranularNode()

{

}

void PGranularNode::initialize()

{

    mTempBuffer = std::make_shared< ci::audio::Buffer >( getFramesPerBlock() );

    mRandomOffset.reset( new RandomGenerator( getSampleRate() / 100 ) ); // divided by 100 corresponds to times 0.01 in the time domain 

    /* create the PGranular object for looping */

    mPGranularLoop.reset( new collidoscope::PGranular<float, RandomGenerator, PGranularNode>( mGrainBuffer->getData(), mGrainBuffer->getNumFrames(), getSampleRate(), *mRandomOffset, *this, -1 ) );

    /* create the PGranular object for notes */

    for ( size_t i = 0; i < kMaxVoices; i++ ){

        mPGranularNotes[i].reset( new collidoscope::PGranular<float, RandomGenerator, PGranularNode>( mGrainBuffer->getData(), mGrainBuffer->getNumFrames(), getSampleRate(), *mRandomOffset, *this, i ) );

    }

}

void PGranularNode::process (ci::audio::Buffer *buffer )

{

    // only update PGranular if the atomic value has changed from the previous time

    const boost::optional<size_t> selectionSize = mSelectionSize.get();

    if ( selectionSize ){

        mPGranularLoop->setSelectionSize( *selectionSize );

        for ( size_t i = 0; i < kMaxVoices; i++ ){

            mPGranularNotes[i]->setSelectionSize( *selectionSize );

        }

    }

    const boost::optional<size_t> selectionStart = mSelectionStart.get();

    if ( selectionStart ){

        mPGranularLoop->setSelectionStart( *selectionStart );

        for ( size_t i = 0; i < kMaxVoices; i++ ){

            mPGranularNotes[i]->setSelectionStart( *selectionStart );

        }

    }

    const boost::optional<double> grainDurationCoeff = mGrainDurationCoeff.get();

    if ( grainDurationCoeff ){

        mPGranularLoop->setGrainsDurationCoeff( *grainDurationCoeff );

        for ( size_t i = 0; i < kMaxVoices; i++ ){

            mPGranularNotes[i]->setGrainsDurationCoeff( *grainDurationCoeff );

        }

    }

    // check messages to start/stop notes or loop 

    size_t availableRead = mNoteMsgRingBufferPack.getBuffer().getAvailableRead();

    mNoteMsgRingBufferPack.getBuffer().read( mNoteMsgRingBufferPack.getExchangeArray(), availableRead );

    for ( size_t i = 0; i < availableRead; i++ ){

        handleNoteMsg( mNoteMsgRingBufferPack.getExchangeArray()[i] );

    }

    // process loop if not idle 

    if ( !mPGranularLoop->isIdle() ){

        /* buffer is one channel only so I can use getData */

        mPGranularLoop->process( buffer->getData(), mTempBuffer->getData(), buffer->getSize() );

    }

    // process notes if not idle 

    for ( size_t i = 0; i < kMaxVoices; i++ ){

        if ( mPGranularNotes[i]->isIdle() )

            continue;

        mPGranularNotes[i]->process( buffer->getData(), mTempBuffer->getData(), buffer->getSize() );

        if ( mPGranularNotes[i]->isIdle() ){

            // this note became idle so update mMidiNotes

            mMidiNotes[i] = kNoMidiNote;

        }

    }

}

// Called back when new grnular is triggered of turned off. Sends notification message to graphic thread.

void PGranularNode::operator()( char msgType, int ID ) {

    switch ( msgType ){

    case 't':  { // trigger 

        CursorTriggerMsg msg = makeCursorTriggerMsg( Command::TRIGGER_UPDATE, ID ); // put ID 

        mTriggerRingBuffer.write( &msg, 1 );

    };

        break;

    case 'e': // end envelope 

        CursorTriggerMsg msg = makeCursorTriggerMsg( Command::TRIGGER_END, ID ); // put ID 

        mTriggerRingBuffer.write( &msg, 1 );

        break;

    }

}

void PGranularNode::handleNoteMsg( const NoteMsg &msg )

{

    switch ( msg.cmd ){

    case Command::NOTE_ON: {

        bool synthFound = false;

        for ( int i = 0; i < kMaxVoices; i++ ){

            // note was already on, so re-attack

            if ( mMidiNotes[i] == msg.midiNote ){

                mPGranularNotes[i]->noteOn( msg.rate );

                synthFound = true;

                break;

            }

        }

        if ( !synthFound ){

            // then look for a free synth 

            for ( int i = 0; i < kMaxVoices; i++ ){

                if ( mMidiNotes[i] == kNoMidiNote ){

                    mPGranularNotes[i]->noteOn( msg.rate );

                    mMidiNotes[i] = msg.midiNote;

                    synthFound = true;

                    break;

                }

            }

        }

    };

        break;

    case Command::NOTE_OFF: {

        for ( int i = 0; i < kMaxVoices; i++ ){

            if ( !mPGranularNotes[i]->isIdle() && mMidiNotes[i] == msg.midiNote ){

                mPGranularNotes[i]->noteOff();

                break;

            }

        }

    };

        break;

    case Command::LOOP_ON: {

        mPGranularLoop->noteOn( 1.0 );

    };

        break;

    case Command::LOOP_OFF: {

        mPGranularLoop->noteOff();

    };

        break;

    default:

        break;

    }

}