gistfile1.txt

OSStatus playbackCallback(void * inRefCon,
                          AudioUnitRenderActionFlags * ioActionFlags,
                          const AudioTimeStamp * inTimeStamp,
                          UInt32 inBusNumber,
                          UInt32 inNumberFrames,
                          AudioBufferList * ioData) {

   AudioController *THIS = (__bridge AudioController *)inRefCon;

   // test
   static int a = 0;
   a++;
   printf("playback %i \n", a);
   
   
   
   

   // temp reference to buffer to fill
   float * bufferToFill = ioData->mBuffers[0].mData;
   
   
   int start = THIS->_waveStart;
   int end = THIS->_waveEnd;
   float lfoRate = THIS->_lfoRate;
   float lfoAmount = THIS->_lfoAmount;
   
   
   if (end <= 0 || start <= 0) {
      return noErr;
   }

   
   //  clear outside of loop points
   for (int x = 0;  x < start; x++) {
      THIS->samplesBuffer[x] = 0;
   }
   for (int x = end;  x < 1000; x++) {
      THIS->samplesBuffer[x] = 0;
   }



// write samples to buffer
   for (int x = 0; x < inNumberFrames; x++) {
      
      THIS->timeIndex++;
      
      // reset to loop begin at loop end
      if (THIS.bufferIndex >= end) THIS.bufferIndex = start;
      
      
      THIS->samplesBuffer[THIS.bufferIndex] += lfoAmount;
      if (THIS->timeIndex % (int)lfoRate == 0) lfoAmount = -lfoAmount;
      
      
      // keep values within range -1 - 1
      if (THIS->samplesBuffer[THIS.bufferIndex] > 1) THIS->samplesBuffer[THIS.bufferIndex] = 1;
      if (THIS->samplesBuffer[THIS.bufferIndex] < -1) THIS->samplesBuffer[THIS.bufferIndex] = -1;
      

      
      printf("val: %f \n", THIS->samplesBuffer[x]);
      
      bufferToFill[x] = THIS->samplesBuffer[THIS.bufferIndex];
      
      THIS.bufferIndex++;

   }
   
   // assign custom buffer to playback buffer
   ioData->mBuffers[0].mData = THIS->samplesBuffer;
   
   return noErr;
}