EXTERN void libpd_lock(void);
EXTERN void libpd_unlock(void);

static pthread_mutex_t libpd_mutex = PTHREAD_MUTEX_INITIALIZER;

 

void libpd_lock() {
  pthread_mutex_lock(&libpd_mutex);
}

 

void libpd_unlock() {
  pthread_mutex_unlock(&libpd_mutex);
}

#ifndef PLUGINPROCESSOR_H_INCLUDED
#define PLUGINPROCESSOR_H_INCLUDED

 

#include "../JuceLibraryCode/JuceHeader.h"

 

extern "C"
{
#include "z_libpd.h"
#include "m_imp.h"
}

class TestMultiInstanceAudioProcessor  : public AudioProcessor
{
public:
    
    TestMultiInstanceAudioProcessor();
    ~TestMultiInstanceAudioProcessor();
  
    void prepareToPlay (double sampleRate, int samplesPerBlock);
    void releaseResources();
    void processBlock (AudioSampleBuffer& buffer, MidiBuffer& midiMessages);

 

    /*

       Other auto-generated functions

        ----
     */ 

 

private:

 

    t_pdinstance *_pdInstance;    
   
    float **_juceIn;
    float **_juceOut;
    float *_pdIn;
    float *_pdOut;
    float _ticks;
    float _blockSize;
    void *_patchHandle;

 

};

 

#endif  // PLUGINPROCESSOR_H_INCLUDED

#include "PluginProcessor.h"
#include "PluginEditor.h"

TestMultiInstanceAudioProcessor::TestMultiInstanceAudioProcessor()
{
  //Initializing pd instance
  _pdInstance = pdinstance_new();
  
  
  /// Init pd and enable dsp
  libpd_lock();
  pd_setinstance(_pdInstance);
  libpd_init();
  libpd_start_message(1);
  libpd_add_float(1.0f);
  libpd_finish_message("pd", "dsp");
  libpd_unlock();
  //Init pd buffers
  _juceIn = NULL;
  _juceOut = NULL;
  _pdIn = NULL;
  _pdOut = NULL;
}

 

TestMultiInstanceAudioProcessor::~TestMultiInstanceAudioProcessor()
{
  if (_juceIn)
  {
    for (int i = 0; i < getNumInputChannels(); ++i)
      delete _juceIn[i];
    delete _juceIn;
    for (int i = 0; i < getNumOutputChannels(); ++i)
      delete _juceOut[i];
    delete _juceOut;
    delete _pdIn;
    delete _pdOut;
  }
  delete _pdInstance;
}

void TestMultiInstanceAudioProcessor::prepareToPlay (double sampleRate, int samplesPerBlock)
{
  //Init libpd audio
  libpd_lock();
  pd_setinstance(_pdInstance);
  libpd_init_audio(getNumInputChannels(),
                   getNumOutputChannels(),
                   sampleRate);
  juce::String patchPath = juce::File::getSpecialLocation(juce::File::currentApplicationFile).getParentDirectory().getFullPathName();
  _patchHandle = libpd_openfile("440.pd",
                                patchPath.toRawUTF8());
  libpd_unlock();
  //Init buffers
  _juceIn = new float*[getNumInputChannels()];
  for (int i = 0; i < getNumInputChannels(); ++i)
    _juceIn[i] = new float[samplesPerBlock];
  _juceOut = new float*[getNumOutputChannels()];
  for (int i = 0; i < getNumOutputChannels(); ++i)
    _juceOut[i] = new float[samplesPerBlock];
  _pdIn = new float[getNumInputChannels() * samplesPerBlock];
  _pdOut = new float[getNumOutputChannels() * samplesPerBlock];
  //Settings ticks
  _ticks = samplesPerBlock / libpd_blocksize();
  _blockSize = samplesPerBlock;
}

 

void TestMultiInstanceAudioProcessor::releaseResources()
{
  if (_juceIn)
  {
    for (int i = 0; i < getNumInputChannels(); ++i)
      delete _juceIn[i];
    delete _juceIn;
    for (int i = 0; i < getNumOutputChannels(); ++i)
      delete _juceOut[i];
    delete _juceOut;
    delete _pdIn;
    delete _pdOut;
    _juceIn = NULL;
    _juceOut = NULL;
    _pdIn = NULL;
    _pdOut = NULL;
  }
  if (_patchHandle) {
    libpd_lock();
    pd_setinstance(_pdInstance);
    libpd_closefile(_patchHandle);
    libpd_unlock();
  }
}

 

void TestMultiInstanceAudioProcessor::processBlock (AudioSampleBuffer& buffer, MidiBuffer& midiMessages)
{
  libpd_lock();
  pd_setinstance(_pdInstance);
  libpd_process_float(_ticks, _pdIn, _pdOut);
  libpd_unlock();
  for (int i = 0; i < _blockSize * getNumOutputChannels(); ++i)
    for (int channel = 0; channel < getNumOutputChannels(); ++channel)
      _juceOut[channel][i / getNumOutputChannels()] = _pdOut[i];
  for (int channel = 0; channel < getNumOutputChannels(); ++channel)
    buffer.copyFrom(channel, 0, _juceOut[channel], _blockSize);
}

/*

  Other autogenerated functions 

  ...

*/