Method Process

libraries/lib-mixer/EffectStage.cpp:295–345

}

bool EffectStage::Process(EffectInstance &instance,
   size_t channel, const Buffers &data, size_t curBlockSize,
   size_t outBufferOffset) const
{
   size_t processed{};
   try {
      const auto positions = mInBuffers.Positions();
      const auto nPositions = mInBuffers.Channels();
      // channel may be nonzero in the case of a plug-in that only reads
      // one channel at a time, so multiple instances are made to mix stereo
      assert(channel <= nPositions);
      std::vector<float *> inPositions(
         positions + channel, positions + nPositions - channel);
      // When the plug-in expects many input channels, replicate the last
      // buffer (assumed to be zero-filled) as dummy input
      inPositions.resize(
         instance.GetAudioInCount() - channel, inPositions.back());

      std::vector<float *> advancedOutPositions;
      const auto size = instance.GetAudioOutCount() - channel;
      advancedOutPositions.reserve(size);

      auto outPositions = data.Positions();
      // It is assumed that data has at least one dummy buffer last
      auto channels = data.Channels();
      // channel may be nonzero in the case of a plug-in that only writes
      // one channel at a time, so multiple instances are made to mix stereo
      for (size_t ii = channel; ii < channels; ++ii)
         advancedOutPositions.push_back(outPositions[ii] + outBufferOffset);
      // When the plug-in expects many output channels, replicate the last
      // as dummy output
      advancedOutPositions.resize(size, advancedOutPositions.back());

      processed = instance.ProcessBlock(mSettings,
         inPositions.data(), advancedOutPositions.data(), curBlockSize);
   }
   catch (const AudacityException &) {
      // PRL: Bug 437:
      // Pass this along to our application-level handler
      throw;
   }
   catch (...) {
      // PRL:
      // Exceptions for other reasons, maybe in third-party code...
      // Continue treating them as we used to, but I wonder if these
      // should now be treated the same way.
      return false;
   }

   return (processed == curBlockSize);
}

sampleCount EffectStage::Remaining() const
{