sound.hpp

#pragma once
#include <ossia/audio/fade.hpp>
#include <ossia/dataflow/audio_stretch_mode.hpp>
#include <ossia/dataflow/node_process.hpp>
#include <ossia/dataflow/nodes/media.hpp>
#include <ossia/dataflow/nodes/timestretch/raw_stretcher.hpp>
#include <ossia/dataflow/nodes/timestretch/repitch_stretcher.hpp>
#include <ossia/dataflow/nodes/timestretch/rubberband_stretcher.hpp>
#include <ossia/dataflow/port.hpp>
#include <ossia/dataflow/sample_to_float.hpp>
#include <ossia/detail/pod_vector.hpp>
#include <ossia/detail/variant.hpp>
 
#include <algorithm>
 
namespace ossia
{
namespace snd
{
struct sample_read_info
{
  int64_t samples_to_read{};
  int64_t samples_to_write{};
};
 
inline auto
sample_info(int64_t bufferSize, double durationRatio, const ossia::token_request& t)
{
  sample_read_info _;
  if(t.paused())
    return _;
 
  if(t.speed == 0.0)
    return _;
 
  _.samples_to_read = t.physical_read_duration(durationRatio);
 
  const auto room = t.safe_physical_write_duration(durationRatio, bufferSize);
  const auto tick_dur = t.physical_write_duration(durationRatio);
  _.samples_to_write = std::min(tick_dur, std::max<int64_t>(0, room));
 
  return _;
}
 
// Output samples per input sample of the material.
inline double rate_ratio(int64_t material_rate, int64_t graph_rate) noexcept
{
  if(material_rate <= 0 || graph_rate <= 0 || material_rate == graph_rate)
    return 1.;
  return double(graph_rate) / double(material_rate);
}
 
inline void
perform_upmix(const std::size_t upmix, const std::size_t chan, ossia::audio_port& ap)
{
  // Upmix
  if(upmix != 0)
  {
    if(upmix < chan)
    {
      /* TODO
  // Downmix
  switch(upmix)
  {
    case 1:
    {
      for(std::size_t i = 1; i < chan; i++)
      {
        if(ap.channel(0).size() < ap.channel(i).size())
          ap.channel(0).resize(ap.channel(i).size());
 
        for(std::size_t j = 0; j < ap.channel(i).size(); j++)
          ap.channel(0)[j] += ap.channel(i)[j];
      }
    }
    default:
      // TODO
      break;
  }
  */
    }
    else if(upmix > chan)
    {
      switch(chan)
      {
        case 1: {
          for(std::size_t chan = 1; chan < upmix; ++chan)
            ap.channel(chan).assign(ap.channel(0).begin(), ap.channel(0).end());
          break;
        }
        default:
          // TODO
          break;
      }
    }
  }
}
 
inline void perform_start_offset(const std::size_t start, ossia::audio_port& ap)
{
  if(start != 0)
  {
    ap.get().insert(ap.get().begin(), start, ossia::audio_channel{});
  }
}
}
 
template <typename T>
struct at_end
{
  T func;
  at_end(T t)
      : func{t}
  {
  }
  ~at_end() { func(); }
};
 
struct resampler
{
  enum
  {
    RawStretcher = 0,
    RubberbandStretcher = 1,
    RepitchStretcher = 2
  };
  [[nodiscard]] int64_t next_sample_to_read() const noexcept
  {
    return ossia::visit(
        [](auto& stretcher) noexcept { return stretcher.next_sample_to_read; },
        m_stretch);
  }
 
  // Warm-up input samples needed before stretcher output aligns with input.
  [[nodiscard]] int64_t start_delay() const noexcept
  {
    return ossia::visit(
        [](auto& stretcher) noexcept -> int64_t { return stretcher.start_delay(); },
        m_stretch);
  }
 
  void transport(int64_t date)
  {
    ossia::visit(
        [=](auto& stretcher) noexcept { return stretcher.transport(date); }, m_stretch);
  }
 
  void reset(
      int64_t date, ossia::audio_stretch_mode mode, std::size_t channels,
      std::size_t materialSampleRate, std::size_t graphSampleRate = 0)
  {
    if(graphSampleRate == 0)
      graphSampleRate = materialSampleRate;
    [[maybe_unused]] const bool converts
        = materialSampleRate != graphSampleRate && materialSampleRate > 0
          && graphSampleRate > 0;
    // TODO use the date parameter to buffer ! else transport won't work
    switch(mode)
    {
      default:
      case ossia::audio_stretch_mode::None: {
#if defined(OSSIA_ENABLE_LIBSAMPLERATE)
        if(converts)
        {
          constexpr auto preset = get_samplerate_preset(
              ossia::audio_stretch_mode::Repitch);
          if(auto s = ossia::get_if<RepitchStretcher>(&m_stretch);
             s && s->repitchers.size() == channels && s->preset == preset)
          {
            s->transport(date);
          }
          else
          {
            m_stretch.emplace<repitch_stretcher>(preset, channels, 1024, date);
          }
          break;
        }
#endif
        if(auto s = ossia::get_if<RawStretcher>(&m_stretch))
        {
          s->transport(date);
        }
        else
        {
          m_stretch.emplace<RawStretcher>(date);
        }
        break;
      }
 
#if defined(OSSIA_ENABLE_RUBBERBAND)
      case ossia::audio_stretch_mode::RubberBandStandard:
      case ossia::audio_stretch_mode::RubberBandPercussive:
      case ossia::audio_stretch_mode::RubberBandStandardHQ:
      case ossia::audio_stretch_mode::RubberBandPercussiveHQ: {
        const auto preset = get_rubberband_preset(mode);
        if(auto s = ossia::get_if<RubberbandStretcher>(&m_stretch);
           s && s->options == preset)
        {
          s->transport(date);
        }
        else
        {
          m_stretch.emplace<rubberband_stretcher>(
              preset, channels, materialSampleRate, date);
        }
        ossia::get<RubberbandStretcher>(m_stretch)
            .set_rate_ratio(snd::rate_ratio(materialSampleRate, graphSampleRate));
        break;
      }
#endif
 
#if defined(OSSIA_ENABLE_LIBSAMPLERATE)
      case ossia::audio_stretch_mode::Repitch:
      case ossia::audio_stretch_mode::RepitchMediumQ:
      case ossia::audio_stretch_mode::RepitchFastestQ: {
        const auto preset = get_samplerate_preset(mode);
        if(auto s = ossia::get_if<RepitchStretcher>(&m_stretch);
           s && s->repitchers.size() == channels && s->preset == preset)
        {
          s->transport(date);
        }
        else
        {
          // FIXME why 1024 here ?!
          m_stretch.emplace<repitch_stretcher>(preset, channels, 1024, date);
        }
        break;
      }
#endif
    }
 
    // A mode whose backend is compiled out falls back to raw_stretcher.
    m_stretching = (mode != ossia::audio_stretch_mode::None)
                   && (m_stretch.index() != RawStretcher);
  }
 
  template <typename T>
  void
  run(T& audio_fetcher, const ossia::token_request& t, ossia::exec_state_facade e,
      double tempo_ratio, double rate_ratio, std::size_t chan, std::size_t len,
      int64_t samples_to_read, int64_t samples_to_write, int64_t samples_offset,
      const ossia::mutable_audio_span<double>& ap)
  {
    ossia::visit(
        [&](auto& stretcher) {
      stretcher.run(
          audio_fetcher, t, e, tempo_ratio, rate_ratio, chan, len, samples_to_read,
          samples_to_write, samples_offset, ap);
        },
        m_stretch);
  }
 
  [[nodiscard]] bool stretch() const noexcept { return m_stretching; }
 
private:
  bool m_stretching{};
 
  ossia::variant<
      raw_stretcher
#if defined(OSSIA_ENABLE_RUBBERBAND)
      ,
      rubberband_stretcher
#endif
#if defined(OSSIA_ENABLE_LIBSAMPLERATE)
      ,
      repitch_stretcher
#endif
      >
      m_stretch;
};
 
struct sound_processing_info
{
  time_value m_prev_date{time_value::infinite_min};
 
  time_value m_loop_duration{};
  time_value m_start_offset{};
 
  double tempo{};
 
  int64_t m_loop_duration_samples{};
  int64_t m_start_offset_samples{};
 
  double m_last_stretch{1.0};
  ossia::resampler m_resampler{};
 
  bool m_loops{};
 
  void set_loop_info(
      ossia::time_value loop_duration, ossia::time_value start_offset, bool loops)
  {
    m_loop_duration = loop_duration;
    m_start_offset = start_offset;
    m_loops = loops;
  }
 
  void set_resampler(ossia::resampler&& r)
  {
    auto date = m_resampler.next_sample_to_read();
    m_resampler = std::move(r);
    m_resampler.transport(date);
  }
 
  void set_native_tempo(double v) { tempo = v; }
 
  // File sample an already-playing sound has reached at a given model date,
  // i.e. where a sound dropped in mid-playback must seek to align with it.
  //
  // When stretching, both the model clock and the file consumption scale
  // with the live tempo: the interval advances its date by
  // tempo / root_tempo model samples per physical sample, and the stretcher
  // consumes tempo / file_tempo file samples per physical sample. Their
  // ratio is root_tempo / file_tempo whatever the transport tempo, tempo
  // curve or speed are doing, so the file position is a pure function of
  // the model date and the file's own tempo. Scaling by the *live* tempo
  // here - as this used to do - lands wrong by a factor of
  // live_tempo / root_tempo, i.e. it is only right at 120 BPM.
  //
  // In raw mode the file advances at one sample per physical sample while
  // the model still runs at tempo / root_tempo, so there the live tempo is
  // exactly what is needed to unscale the date; when it is not known
  // (timeline_tempo == 0), the date is used as-is.
  [[nodiscard]] int64_t file_sample_for_model_time(
      time_value date, double timeline_tempo,
      int file_sample_rate) const noexcept
  {
    const int64_t base = to_sample(date, file_sample_rate);
    if(m_resampler.stretch() && tempo > 0.0)
      return int64_t(std::llround(double(base) * ossia::root_tempo / tempo));
 
    const double abs_tempo = std::abs(timeline_tempo);
    if(abs_tempo > 0.0)
      return int64_t(std::llround(double(base) * ossia::root_tempo / abs_tempo));
    return base;
  }
 
  double update_stretch(
      const ossia::token_request& t, const ossia::exec_state_facade& e,
      double rate_ratio = 1.) noexcept
  {
    double stretch_ratio = 1.;
    double model_ratio = 1.;
    if(tempo != 0. && m_resampler.stretch())
    {
      model_ratio = ossia::root_tempo / this->tempo;
      stretch_ratio = this->tempo / t.tempo;
    }
 
    if(!(rate_ratio > 0.))
      rate_ratio = 1.;
    const double to_material = e.modelToSamples() * model_ratio / rate_ratio;
 
    m_loop_duration_samples = m_loop_duration.impl * to_material;
    m_start_offset_samples = m_start_offset.impl * to_material;
    return stretch_ratio;
  }
};
 
class sound_node
    : public ossia::nonowning_graph_node
    , public sound_processing_info
{
public:
  virtual void transport(time_value date) = 0;
 
  // Tempo-aware overload; resampling subclasses override to seek the file
  // pointer correctly when file_tempo != timeline_tempo. current_tempo == 0
  // means unknown and falls back to the non-stretch path.
  virtual void transport(
      time_value date, const ossia::tick_transport_info& transport_info)
  {
    (void)transport_info;
    transport(date);
  }
};
 
class dummy_sound_node final : public sound_node
{
public:
  ossia::audio_outlet audio_out;
  dummy_sound_node()
  {
    // Add a dummy outlet so that interval can connect propagation to it
    m_outlets.push_back(&audio_out);
  }
 
  std::string label() const noexcept override { return "dummy_sound_node"; }
 
  void transport(time_value date) override { }
 
  void run(const ossia::token_request& t, ossia::exec_state_facade e) noexcept override
  {
  }
};
 
#if defined(OSSIA_SCENARIO_DATAFLOW)
class sound_process final : public ossia::node_process
{
public:
  using ossia::node_process::node_process;
 
protected:
  void state(const ossia::token_request& req) override
  {
    // TODO here we should also pass the execution state so that we can
    // leverage the timing info & transform loop_duration / start_offset in
    // samples right here...
    static_cast<sound_node&>(*this->node)
        .set_loop_info(m_loop_duration, m_start_offset, m_loops);
 
    // Start offset and looping are done manually inside the sound nodes
    // since it is much more efficient in this case
    // (see fetch_audio)
    node->request(req);
  }
 
  void offset_impl(time_value date) override
  {
    static_cast<sound_node&>(*this->node).transport(date);
  }
  void transport_impl(time_value date) override
  {
    static_cast<sound_node&>(*this->node).transport(date);
  }
  void transport_impl(
      time_value date, const ossia::tick_transport_info& info) override
  {
    static_cast<sound_node&>(*this->node).transport(date, info);
  }
};
#endif
 
}