Method ProcessOne

libraries/lib-builtin-effects/NormalizeBase.cpp:307–366

ProcessOne() takes a track, transforms it to bunch of buffer-blocks, and executes ProcessData, on it... uses mMult and offset to normalize a track. mMult must be set before this is called

// uses mMult and offset to normalize a track.
// mMult must be set before this is called
bool NormalizeBase::ProcessOne(
   WaveChannel& track, const TranslatableString& msg, double& progress,
   float offset)
{
   bool rc = true;

   // Transform the marker timepoints to samples
   auto start = track.TimeToLongSamples(mCurT0);
   auto end = track.TimeToLongSamples(mCurT1);

   // Get the length of the buffer (as double). len is
   // used simply 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();

   // Initiate a processing buffer.  This buffer will (most likely)
   // be shorter than the length of the track being processed.
   Floats buffer { track.GetMaxBlockSize() };

   // Go through the track one buffer at a time. s counts which
   // sample the current buffer starts at.
   auto s = start;
   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
      const auto block =
         limitSampleBufferSize(track.GetBestBlockSize(s), end - s);

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

      // Process the buffer.
      ProcessData(buffer.get(), block, offset);

      // Copy the newly-changed samples back onto the track.
      if (!track.SetFloats(buffer.get(), s, block))
      {
         rc = false;
         break;
      }

      // Increment s one blockfull of samples
      s += block;

      // Update the Progress meter
      if (TotalProgress(
             progress + ((s - start).as_double() / len) /
                           double(2 * GetNumWaveTracks()),
             msg))
      {
         rc = false; // lda .. break, not return, so that buffer is deleted
         break;
      }
   }
   progress += 1.0 / double(2 * GetNumWaveTracks());

   // Return true because the effect processing succeeded ... unless cancelled