SquidgeDSP/plugins/SquidgeDistortion/SquidgeDistortion.cpp

#include "DistrhoDetails.hpp"
#include "DistrhoPlugin.hpp"
#include "DistrhoPluginInfo.h"

#include <cmath>

#include "../../core/Clipper.hpp"
#include "../../core/Filter.hpp"
#include "../../core/Gain.hpp"
#include "../../core/Mixer.hpp"

START_NAMESPACE_DISTRHO

const int BUFFER_SIZE = 16384;

struct AudioBuffers {
  float clippedL[BUFFER_SIZE];
  float clippedR[BUFFER_SIZE];
  float lpL[BUFFER_SIZE];
  float lpR[BUFFER_SIZE];
};

class SquidgeDistortion : public Plugin {

public:
  enum MixerChannels { kChannelDry, kChannelWet, kChannelCount };
  enum Parameters {
    kParamGain,
    kParamClipMode,
    kParamFilter,
    kParamFilterFeedback,
    kParamMixVolume,
    kParamResonance,
    kParameterCount // must be last
  };
  SquidgeDistortion()
      : Plugin(kParameterCount, 0, 0), gain_(2.0f), mixer_(1.0f), filter_(440) {
    mixer_.setInputGain(kChannelDry, 0.0f);
    mixer_.setInputGain(kChannelWet, 1.0f);
  }

protected:
  const char *getLabel() const override { return "SquidgeDistortion"; }
  const char *getDescription() const override {
    return "Simple distortion plugin.";
  }
  const char *getMaker() const override { return "SquidgeSoft"; }
  const char *getLicense() const override { return "GPL3"; }
  uint32_t getVersion() const override { return d_version(0, 1, 0); }
  int64_t getUniqueId() const override { return d_cconst('S', 'Q', 'D', 'T'); }

  void initParameter(uint32_t index, Parameter &parameter) override {
    switch (index) {
    case kParamGain:
      parameter.name = "Gain";
      parameter.symbol = "gain";
      parameter.ranges.min = 1.0f;
      parameter.ranges.def = 2.0f;
      parameter.ranges.max = 10.0f;
      parameter.hints = kParameterIsAutomatable;
      break;
    case kParamClipMode:
      parameter.name = "Clip Mode";
      parameter.symbol = "clipmode";
      parameter.ranges.min = 0.0f;
      parameter.ranges.def = 0.0f;
      parameter.ranges.max = Clipper::kClipperModeCount - 1;
      parameter.hints = kParameterIsAutomatable | kParameterIsInteger;
      parameter.enumValues.count = Clipper::kClipperModeCount;
      parameter.enumValues.restrictedMode = true;

      static const ParameterEnumerationValue
          sClipModes[Clipper::kClipperModeCount] = {
              {0.0f, "Soft"}, {1.0f, "Hard"}, {2.0f, "Fold"}};
      parameter.enumValues.values =
          const_cast<ParameterEnumerationValue *>(sClipModes);
      break;
    case kParamFilter:
      parameter.name = "Filter";
      parameter.symbol = "filter";
      parameter.ranges.min = 20.0f;
      parameter.ranges.def = 1000.0f;
      parameter.ranges.max = 10000.0f;
      parameter.hints = kParameterIsAutomatable;
      break;
    case kParamFilterFeedback:
      parameter.name = "Feedback";
      parameter.symbol = "filterfeedback";
      parameter.ranges.min = 0.0f;
      parameter.ranges.def = 0.0f;
      parameter.ranges.max = 0.95f;
      parameter.hints = kParameterIsAutomatable;
      break;
    case kParamMixVolume:
      parameter.name = "Dry/Wet";
      parameter.symbol = "drywetvolume";
      parameter.ranges.min = 0.0f;
      parameter.ranges.def = 1.0f;
      parameter.ranges.max = 1.0f;
      parameter.hints = kParameterIsAutomatable;
      break;
    case kParamResonance:
      parameter.name = "Resonance";
      parameter.symbol = "resonance";
      parameter.ranges.min = 0.0f;
      parameter.ranges.def = 0.1f;
      parameter.ranges.max = 1.0f;
      parameter.hints = kParameterIsAutomatable;
      break;
    }
  }

  float getParameterValue(uint32_t index) const override {
    switch (index) {
    case kParamGain:
      return gain_.getGain();
    case kParamClipMode:
      return (float)clipper_.getMode();
    case kParamFilter:
      return (float)filter_.getCutOff();
    case kParamFilterFeedback:
      return (float)filter_.getFeedback();
    case kParamMixVolume:
      return mixer_.getInputGain(kChannelWet);
    case kParamResonance:
      return (float)filter_.getResonance();
    }
    return 0.0f;
  }

  void setParameterValue(uint32_t index, float value) override {
    switch (index) {
    case kParamGain:
      gain_.setGain(value);
      break;
    case kParamClipMode:
      value = std::fmin(std::fmax(value, 0.0f),
                        static_cast<float>(Clipper::kClipperModeCount - 1));
      clipper_.setMode(static_cast<Clipper::ClipperMode>(std::lround(value)));
      break;
    case kParamFilter:
      filter_.setCutOff(value);
      break;
    case kParamFilterFeedback:
      filter_.setFeedback(value);
      break;
    case kParamMixVolume:
      mixer_.setInputGain(kChannelWet, value);
      mixer_.setInputGain(kChannelDry, 1.0f - value);
      break;
    case kParamResonance:
      filter_.setResonance(value);
      break;
    }
  }

  void run(const float **inputs, float **outputs, uint32_t frames) override {
    if (frames > BUFFER_SIZE) {
      for (uint32_t i = 0; i < frames; ++i) {
        outputs[0][i] = inputs[0][i];
        outputs[1][i] = inputs[1][i];
      }
      return;
    }
    gain_.processStereo(inputs[0], inputs[1], buffers_.clippedL,
                        buffers_.clippedR, frames);
    clipper_.processStereo(buffers_.clippedL, buffers_.clippedR,
                           buffers_.clippedL, buffers_.clippedR, frames);
    filter_.processStereo(buffers_.clippedL, buffers_.clippedR, buffers_.lpL,
                          buffers_.lpR, frames);

    const float *inputsL[2] = {inputs[0], buffers_.lpL};
    const float *inputsR[2] = {inputs[1], buffers_.lpR};

    mixer_.processStereo(inputsL, inputsR, outputs[0], outputs[1], frames);
  }

  void sampleRateChanged(double newSr) override {
    filter_.setSampleRate(static_cast<float>(newSr));
  }

private:
  Gain gain_;
  Clipper clipper_;
  Mixer<2> mixer_;
  Filter filter_;
  AudioBuffers buffers_;

  DISTRHO_DECLARE_NON_COPYABLE_WITH_LEAK_DETECTOR(SquidgeDistortion);
};

Plugin *createPlugin() { return new SquidgeDistortion(); }

END_NAMESPACE_DISTRHO