DISTRHO-Ports/ports/vitalium/source/common/wavetable/wave_source.cpp

/* Copyright 2013-2019 Matt Tytel
 *
 * vital is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * vital is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with vital.  If not, see <http://www.gnu.org/licenses/>.
 */

#include "wave_source.h"
#include "wave_frame.h"
#include "wavetable_component_factory.h"

WaveSource::WaveSource() {
  compute_frame_ = std::make_unique<WaveSourceKeyframe>();
  interpolation_mode_ = kFrequency;
}

WaveSource::~WaveSource() { }

WavetableKeyframe* WaveSource::createKeyframe(int position) {
  WaveSourceKeyframe* keyframe = new WaveSourceKeyframe();
  render(keyframe->wave_frame(), position);
  return keyframe;
}

void WaveSource::render(vital::WaveFrame* wave_frame, float position) {
  compute_frame_->setInterpolationMode(interpolation_mode_);
  interpolate(compute_frame_.get(), position);
  wave_frame->copy(compute_frame_->wave_frame());
}

WavetableComponentFactory::ComponentType WaveSource::getType() {
  return WavetableComponentFactory::kWaveSource;
}

json WaveSource::stateToJson() {
  json data = WavetableComponent::stateToJson();
  data["interpolation"] = interpolation_mode_;
  return data;
}

void WaveSource::jsonToState(json data) {
  WavetableComponent::jsonToState(data);
  interpolation_mode_ = data["interpolation"];
  compute_frame_->setInterpolationMode(interpolation_mode_);
}

vital::WaveFrame* WaveSource::getWaveFrame(int index) {
  return getKeyframe(index)->wave_frame();
}

WaveSourceKeyframe* WaveSource::getKeyframe(int index) {
  WavetableKeyframe* wavetable_keyframe = keyframes_[index].get();
  return dynamic_cast<WaveSourceKeyframe*>(wavetable_keyframe);
}

void WaveSourceKeyframe::copy(const WavetableKeyframe* keyframe) {
  const WaveSourceKeyframe* source = dynamic_cast<const WaveSourceKeyframe*>(keyframe);
  wave_frame_->copy(source->wave_frame_.get());
}

void WaveSourceKeyframe::linearTimeInterpolate(const vital::WaveFrame* from, const vital::WaveFrame* to, float t) {
  for (int i = 0; i < vital::WaveFrame::kWaveformSize; ++i)
    wave_frame_->time_domain[i] = linearTween(from->time_domain[i], to->time_domain[i], t);
  wave_frame_->toFrequencyDomain();
}

void WaveSourceKeyframe::cubicTimeInterpolate(const vital::WaveFrame* prev, const vital::WaveFrame* from,
                                              const vital::WaveFrame* to, const vital::WaveFrame* next,
                                              float range_prev, float range, float range_next, float t) {

  for (int i = 0; i < vital::WaveFrame::kWaveformSize; ++i) {
    wave_frame_->time_domain[i] = cubicTween(prev->time_domain[i], from->time_domain[i],
                                             to->time_domain[i], next->time_domain[i],
                                             range_prev, range, range_next, t);
  }
  wave_frame_->toFrequencyDomain();
}

void WaveSourceKeyframe::linearFrequencyInterpolate(const vital::WaveFrame* from,
                                                    const vital::WaveFrame* to, float t) {
  for (int i = 0; i < vital::WaveFrame::kNumRealComplex; ++i) {
    float amplitude_from = sqrtf(std::abs(from->frequency_domain[i]));
    float amplitude_to = sqrtf(std::abs(to->frequency_domain[i]));
    float amplitude = linearTween(amplitude_from, amplitude_to, t);
    amplitude *= amplitude;

    float phase_from = std::arg(from->frequency_domain[i]);
    float phase_delta = std::arg(std::conj(from->frequency_domain[i]) * to->frequency_domain[i]);
    float phase = phase_from + t * phase_delta;
    if (amplitude_from == 0)
      phase = std::arg(to->frequency_domain[i]);
    wave_frame_->frequency_domain[i] = std::polar(amplitude, phase);
  }

  float dc_from = from->frequency_domain[0].real();
  float dc_to = to->frequency_domain[0].real();
  wave_frame_->frequency_domain[0] = linearTween(dc_from, dc_to, t);

  int last = vital::WaveFrame::kNumRealComplex - 1;
  float last_harmonic_from = from->frequency_domain[last].real();
  float last_harmonic_to = to->frequency_domain[last].real();
  wave_frame_->frequency_domain[last] = linearTween(last_harmonic_from, last_harmonic_to, t);

  wave_frame_->toTimeDomain();
}

void WaveSourceKeyframe::cubicFrequencyInterpolate(const vital::WaveFrame* prev, const vital::WaveFrame* from,
                                                   const vital::WaveFrame* to, const vital::WaveFrame* next,
                                                   float range_prev, float range, float range_next, float t) {
  for (int i = 0; i < vital::WaveFrame::kNumRealComplex; ++i) {
    float amplitude_prev = sqrtf(std::abs(prev->frequency_domain[i]));
    float amplitude_from = sqrtf(std::abs(from->frequency_domain[i]));
    float amplitude_to = sqrtf(std::abs(to->frequency_domain[i]));
    float amplitude_next = sqrtf(std::abs(next->frequency_domain[i]));
    float amplitude = cubicTween(amplitude_prev, amplitude_from, amplitude_to, amplitude_next,
                                 range_prev, range, range_next, t);
    amplitude *= amplitude;

    float phase_delta_from = std::arg(std::conj(prev->frequency_domain[i]) * from->frequency_domain[i]);
    float phase_delta_to = std::arg(std::conj(from->frequency_domain[i]) * to->frequency_domain[i]);
    float phase_delta_next = std::arg(std::conj(to->frequency_domain[i]) * next->frequency_domain[i]);
    float phase_prev = std::arg(prev->frequency_domain[i]);
    float phase_from = phase_prev;
    if (amplitude_from)
      phase_from += phase_delta_from;
    float phase_to = phase_from;
    if (amplitude_to)
      phase_to += phase_delta_to;
    float phase_next = phase_to;
    if (amplitude_next)
      phase_next += phase_delta_next;

    float phase = cubicTween(phase_prev, phase_from, phase_to, phase_next, range_prev, range, range_next, t);
    wave_frame_->frequency_domain[i] = std::polar(amplitude, phase);
  }

  float dc_prev = prev->frequency_domain[0].real();
  float dc_from = from->frequency_domain[0].real();
  float dc_to = to->frequency_domain[0].real();
  float dc_next = next->frequency_domain[0].real();
  wave_frame_->frequency_domain[0] = cubicTween(dc_prev, dc_from, dc_to, dc_next, range_prev, range, range_next, t);

  int last = vital::WaveFrame::kNumRealComplex - 1;
  float last_harmonic_prev = prev->frequency_domain[last].real();
  float last_harmonic_from = from->frequency_domain[last].real();
  float last_harmonic_to = to->frequency_domain[last].real();
  float last_harmonic_next = next->frequency_domain[last].real();
  wave_frame_->frequency_domain[last] = cubicTween(last_harmonic_prev, last_harmonic_from,
                                                   last_harmonic_to, last_harmonic_next, 
                                                   range_prev, range, range_next, t);
  wave_frame_->toTimeDomain();
}

void WaveSourceKeyframe::interpolate(const WavetableKeyframe* from_keyframe,
                                     const WavetableKeyframe* to_keyframe, float t) {
  const WaveSourceKeyframe* from = dynamic_cast<const WaveSourceKeyframe*>(from_keyframe);
  const WaveSourceKeyframe* to = dynamic_cast<const WaveSourceKeyframe*>(to_keyframe);

  if (interpolation_mode_ == WaveSource::kFrequency)
    linearFrequencyInterpolate(from->wave_frame_.get(), to->wave_frame_.get(), t);
  else
    linearTimeInterpolate(from->wave_frame_.get(), to->wave_frame_.get(), t);
}

void WaveSourceKeyframe::smoothInterpolate(const WavetableKeyframe* prev_keyframe,
                                           const WavetableKeyframe* from_keyframe,
                                           const WavetableKeyframe* to_keyframe,
                                           const WavetableKeyframe* next_keyframe, float t) {
  const vital::WaveFrame* prev = dynamic_cast<const WaveSourceKeyframe*>(prev_keyframe)->wave_frame_.get();
  const vital::WaveFrame* from = dynamic_cast<const WaveSourceKeyframe*>(from_keyframe)->wave_frame_.get();
  const vital::WaveFrame* to = dynamic_cast<const WaveSourceKeyframe*>(to_keyframe)->wave_frame_.get();
  const vital::WaveFrame* next = dynamic_cast<const WaveSourceKeyframe*>(next_keyframe)->wave_frame_.get();

  float range_prev = from_keyframe->position() - prev_keyframe->position();
  float range = to_keyframe->position() - from_keyframe->position();
  float range_next = next_keyframe->position() - to_keyframe->position();

  if (interpolation_mode_ == WaveSource::kFrequency)
    cubicFrequencyInterpolate(prev, from, to, next, range_prev, range, range_next, t);
  else
    cubicTimeInterpolate(prev, from, to, next, range_prev, range, range_next, t);
}

json WaveSourceKeyframe::stateToJson() {
  String encoded = Base64::toBase64(wave_frame_->time_domain, sizeof(float) * vital::WaveFrame::kWaveformSize);
  json data = WavetableKeyframe::stateToJson();
  data["wave_data"] = encoded.toStdString();
  return data;
}

void WaveSourceKeyframe::jsonToState(json data) {
  WavetableKeyframe::jsonToState(data);

  MemoryOutputStream decoded(sizeof(float) * vital::WaveFrame::kWaveformSize);
  std::string wave_data = data["wave_data"];
  Base64::convertFromBase64(decoded, wave_data);
  memcpy(wave_frame_->time_domain, decoded.getData(), sizeof(float) * vital::WaveFrame::kWaveformSize);
  wave_frame_->toFrequencyDomain();
}