Loopp/src/looper.cxx

/*
 * Author: Harry van Haaren 2013
 *         harryhaaren@gmail.com
 * 
 *  This program is free software: you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation, either version 3 of the License, or
 *  (at your option) any later version.
 *  
 *  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 for more details.
 *  
 *  You should have received a copy of the GNU General Public License
 *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */


#include "looper.hxx"

#include "config.hxx"

#include <cmath>

#include "jack.hxx"
#include "audiobuffer.hxx"
#include "eventhandler.hxx"
#include "controllerupdater.hxx"

extern Jack* jack;

Looper::Looper(int t) :
  AudioProcessor(),
  TimeObserver(),
  track(t)
{
  uiUpdateConstant= jack->getSamplerate() / 30.f;
  uiUpdateCounter = jack->getSamplerate() / 30.f;
  
  // pre-zero the internal sample
  //tmpRecordBuffer = (float*)malloc( sizeof(float) * MAX_BUFFER_SIZE );
  //memset( tmpRecordBuffer, 0, sizeof(float) * MAX_BUFFER_SIZE );
  
  for(int i = 0; i < 10; i++ )
  {
    clips[i] = new LooperClip(track, i);
  }
  
  tmpBuffer.resize( MAX_BUFFER_SIZE );
  
  fpb = 22050;
  
  // init faust pitch shift variables
  fSamplingFreq = jack->getSamplerate();
  IOTA = 0;
  
  //tmpRecordBuffer.resize(MAX_BUFFER_SIZE);
  
  for (int i=0; i<65536; i++)
    fVec0[i] = 0;
  for (int i=0; i<2; i++)
    fRec0[i] = 0;
  semitoneShift = 0.0f;
  windowSize = 1000;
  crossfadeSize = 1000;
}

LooperClip* Looper::getClip(int scene)
{
  return clips[scene];
}

void Looper::setRequestedBuffer(int s, AudioBuffer* ab)
{
  clips[s]->setRequestedBuffer( ab );
}

void Looper::setFpb(int f)
{
  fpb = f;
}

void Looper::process(unsigned int nframes, Buffers* buffers)
{
  // process each clip individually: this allows for playback of one clip,
  // while another clip records.
  for ( int clip = 0; clip < NSCENES; clip++ )
  {
    // handle state of clip, and do what needs doing:
    // record into buffer, play from buffer, etc
    if ( clips[clip]->recording() )
    {
      if ( clips[clip]->recordSpaceAvailable() <  LOOPER_SAMPLES_BEFORE_REQUEST &&
          !clips[clip]->newBufferInTransit() )
      {
        EventLooperClipRequestBuffer e( track, clip, clips[clip]->audioBufferSize() + LOOPER_SAMPLES_UPDATE_SIZE);
        writeToGuiRingbuffer( &e );
        clips[clip]->newBufferInTransit(true);
      }
      
      // copy data from input buffer to recording buffer
      float* input = buffers->audio[Buffers::MASTER_INPUT];
      clips[clip]->record( nframes, input, 0 );
    }
    else if ( clips[clip]->playing() )
    {
      // copy data into tmpBuffer, then pitch-stretch into track buffer
      long targetFrames = clips[clip]->getBeats() * fpb;
      long actualFrames = clips[clip]->getBufferLenght();
      float playSpeed = 1.0;
      
      if ( targetFrames != 0 && actualFrames != 0 )
      {
        playSpeed = float(actualFrames) / targetFrames;
      }
      
      float* out = buffers->audio[Buffers::TRACK_0 + track];
      
      for(unsigned int i = 0; i < nframes; i++ )
      {
        // REFACTOR into system that is better than per sample function calls
        float tmp = clips[clip]->getSample(playSpeed);
        
        float deltaPitch = 12 * log ( playSpeed ) / log (2);
        semitoneShift = -deltaPitch;
        
        // write the pitch-shifted signal to the track buffer
        pitchShift( 1, &tmp, &out[i] );
      }
      
      //printf("Looper %i playing(), speed = %f\n", track, playSpeed );
      
      if ( uiUpdateCounter > uiUpdateConstant )
      {
        jack->getControllerUpdater()->setTrackSceneProgress(track, clip, clips[clip]->getProgress() );
        uiUpdateCounter = 0;
      }
      uiUpdateCounter += nframes;
    }
  
  }
  
  
}

void Looper::pitchShift(int count, float* input, float* output)
{
  float   fSlow0 = windowSize;
  float   fSlow1 = ((1 + fSlow0) - powf(2,(0.08333333333333333f * semitoneShift)));
  float   fSlow2 = (1.0f / crossfadeSize);
  float   fSlow3 = (fSlow0 - 1);
  float* input0 = &input[0];
  //float* output0 = &output[0];
  
  for (int i=0; i<count; i++)
  {
    float fTemp0 = (float)input0[i];
    fVec0[IOTA&65535] = fTemp0;
    fRec0[0] = fmodf((fRec0[1] + fSlow1),fSlow0);
    int iTemp1 = int(fRec0[0]);
    int iTemp2 = (1 + iTemp1);
    float fTemp3 = min((fSlow2 * fRec0[0]), 1.f );
    float fTemp4 = (fSlow0 + fRec0[0]);
    int iTemp5 = int(fTemp4);
    
    *output++ = (float)(((1 - fTemp3) * (((fTemp4 - iTemp5) * 
    fVec0[(IOTA-int((int((1 + iTemp5)) & 65535)))&65535]) + ((0 - ((
    fRec0[0] + fSlow3) - iTemp5)) * fVec0[(IOTA-int((iTemp5 & 65535)))
    &65535]))) + (fTemp3 * (((fRec0[0] - iTemp1) * fVec0[(IOTA-int((int(
    iTemp2) & 65535)))&65535]) + ((iTemp2 - fRec0[0]) * fVec0[(IOTA-int((
    iTemp1 & 65535)))&65535]))));
    
    fRec0[1] = fRec0[0];
    IOTA = IOTA+1;
  }
}