Method ProcessOne

libraries/lib-builtin-effects/TwoPassSimpleMono.cpp:122–229

ProcessOne() takes a track, transforms it to bunch of buffer-blocks, and executes TwoBufferProcessPass1 or TwoBufferProcessPass2 on these blocks

// ProcessOne() takes a track, transforms it to bunch of buffer-blocks,
// and executes TwoBufferProcessPass1 or TwoBufferProcessPass2 on these blocks
bool EffectTwoPassSimpleMono::ProcessOne(WaveChannel &track,
   WaveChannel &outTrack, sampleCount start, sampleCount end)
{
   bool ret;

   // Get the length of the buffer (as double). len is
   // used simple to calculate a progress meter, so it is easier
   // to make it a double now than it is to do it later
   auto len = (end - start).as_double();
   auto maxblock = track.GetMaxBlockSize();

   // Initiate a processing buffer.  This buffer will (most likely)
   // be shorter than the length of the track being processed.
   Floats buffer1{ maxblock };
   Floats buffer2{ maxblock };
   auto samples1 =  limitSampleBufferSize(
      std::min(maxblock, track.GetBestBlockSize(start)), end - start);

   // Get the samples from the track and put them in the buffer
   track.GetFloats(buffer1.get(), start, samples1);

   // Process the first buffer with a null previous buffer
   if (mPass == 0)
      ret = TwoBufferProcessPass1(nullptr, 0, buffer1.get(), samples1);
   else
      ret = TwoBufferProcessPass2(nullptr, 0, buffer1.get(), samples1);
   if (!ret)
      // Return false because the effect failed.
      return false;

   // Go through the track one buffer at a time. s counts which
   // sample the current buffer starts at.
   auto s = start + samples1;
   while (s < end) {
      // Get a block of samples (smaller than the size of the buffer)
      // Adjust the block size if it is the final block in the track
      auto samples2 = limitSampleBufferSize(
         std::min(track.GetBestBlockSize(s), maxblock), end - s);

      // Get the samples from the track and put them in the buffer
      track.GetFloats(buffer2.get(), s, samples2);

      // Process the buffer.  If it fails, clean up and exit.
      if (mPass == 0)
         ret = TwoBufferProcessPass1(buffer1.get(), samples1, buffer2.get(),
            samples2);
      else
         ret = TwoBufferProcessPass2(buffer1.get(), samples1, buffer2.get(),
            samples2);
      if (!ret)
         // Return false because the effect failed.
         return false;

      // Processing succeeded. copy the newly-changed samples back
      // onto the track.
      if (mSecondPassDisabled || mPass != 0) {
         if (!outTrack.SetFloats(buffer1.get(), s - samples1,
            samples1))