Thread: Creating and passing a void through for userdata with portaudio

I am a complete C/C++ noob and been hacking away at my 1st project which is basically just using GitHub - orazdow/PortAudio-Wrapper: C++ wrapper for PortAudio & GitHub - robin1001/beamforming

Where my hack main() .cpp looks something like this

Code:

#include "pa.h"
#include "tdoa.h"
#include "ds.h"
#include "parse-option.h"
#include <chrono>
using namespace std;
using namespace std::chrono;
struct paConfig
{
    int channels;
    int margin;
};


void paFunc(const float* in, float* out, long frames, void* data){    
  auto start = high_resolution_clock::now();    
  int num_channel = 2;
  int margin = 6;
  float *out_pcm = (float *)calloc(sizeof(float), frames);
  int *tdoa = (int *)calloc(sizeof(int), num_channel);
  // rearrange channel data
  float *in_data = (float *)calloc(sizeof(float), 
    frames * num_channel);
  float *beam_data = (float *)calloc(sizeof(float), 
    frames * num_channel);


  for (int j = 0; j < num_channel; j++) {
    for (int k = 0; k < frames; k++) {
      in_data[j + k] = in[k * num_channel + j];
            }
    for (int k = 0; k < frames; k++) {
                beam_data[j + k] = in[k * num_channel + j];
            }
        }        
  // calc delay
  int tao = margin < frames / 2 ? margin : frames / 2;
  GccPhatTdoa(in_data, num_channel, frames, 0, tao, tdoa);
  for (int j = 0; j < num_channel; j++) {
    printf("%d ", tdoa[j]);
    }
  printf("\n");


  DelayAndSum(beam_data, num_channel, frames, tdoa, out_pcm);
  
  float max = 0.0;
  float average = 0.0;
  for (int k = 0; k < frames; k++) {
    out[k] = out_pcm[k];
    float val = out_pcm[k];
    if( val < 0 ) val = -val; /* ABS */
    if( val > max )
       {
         max = val;
         }
    average += val;
    }
    
  average = average / (float)frames;
  printf("sample max amplitude = %f\n", max );
  printf("sample average = %f\n", average );
  auto stop = high_resolution_clock::now();
  auto duration = duration_cast<milliseconds>(stop - start);
  printf("milliseconds = %ld\n", duration);
  free(beam_data);
  free(in_data);
  free(out_pcm);
  free(tdoa);
}


int main(int argc, char *argv[]) {
  const char *usage = "Do delay and sum beamforming\n"
    "Usage: apply-delay-and-sum input_device output_device\n";
  ParseOptions po(usage);


  int input_device = 1;
  po.Register("input_device", &input_device, 
    "multichannel input device index");
  int output_device = 1;
  po.Register("output_device", &output_device, 
    "single channel output device index");
  int frames = 4000;
  po.Register("frames", &frames, 
    "frame buffer size");        
  int channels = 2;
  po.Register("channels", &channels, 
    "mic input channels");
  int margin = 16;
  po.Register("margin", &margin, 
    "constraint for tdoa estimation");
  int sample_rate = 44100;
  po.Register("sample_rate", &sample_rate, 
    "sample rate");
  po.Read(argc, argv);


  //if (po.NumArgs() != 2) {
    //po.PrintUsage();
    //exit(1);
  //}
  struct paConfig config;
  config.channels = channels;
  config.margin = margin;
  Pa a(paFunc, channels, 1, sample_rate, frames, NULL);
  a.listDevices();
  a.getDeviceInfo(input_device);
  a.getDeviceInfo(output_device);
  printf("input=%d output=%d frames=%d channels=%d margin=%d sample_rate=%d", input_device, output_device, frames, channels, margin, sample_rate);
  a.setInputDevice(input_device);
  a.setOutputDevice(output_device);
  a.start(Pa::waitForKey);
  return 0;
  }

Currently the callback call has the userdata set to Null.
`Pa a(paFunc, channels, 1, sample_rate, frames, NULL);`
Where it should come through as 'void* data'
void paFunc(const float* in, float* out, long frames, void* data)

I am presuming a struct with each user parameter I want to send is quite easy but everything I have tried so far has failed and its just my total noobness where you can cast a struct ` /* Cast data passed through stream to our structure. */ paTestData *data = (paTestData*)userData; `

I just can not seen to figure out how and presuming it pretty easy and wondering if anyone can give me a better example than the one at

PortAudio: Writing a Callback Function