comb_filter.h

Go to the documentation of this file.

#pragma once
 
#include "processor.h"
#include "synth_filter.h"
 
#include "memory.h"
#include "one_pole_filter.h"
 
namespace vital {
 
  class CombFilter : public Processor, public SynthFilter {
    public:
      enum FeedbackStyle {
        kComb,            
        kPositiveFlange,  
        kNegativeFlange,  
        kNumFeedbackStyles
      };
 
      enum FilterStyle {
        kLowHighBlend, 
        kBandSpread,   
        kNumFilterStyles
      };
 
      static FeedbackStyle getFeedbackStyle(int style) {
        return static_cast<FeedbackStyle>(style % kNumFeedbackStyles);
      }
 
      static FilterStyle getFilterStyle(int style) {
        return static_cast<FilterStyle>(style / kNumFeedbackStyles);
      }
 
      static constexpr int kNumFilterTypes = kNumFilterStyles * kNumFeedbackStyles;
 
      static constexpr mono_float kBandOctaveRange = 8.0f;
 
      static constexpr mono_float kBandOctaveMin = 0.0f;
 
      static constexpr int kMinPeriod = 2;
 
      static constexpr mono_float kInputScale = 0.5f;
 
      static constexpr mono_float kMaxFeedback = 1.0f;
 
      CombFilter(int size = kMinPeriod);
 
      CombFilter(const CombFilter& other);
 
      virtual ~CombFilter();
 
      virtual Processor* clone() const override {
        return new CombFilter(*this);
      }
 
      void setupFilter(const FilterState& filter_state) override;
 
      virtual void process(int num_samples) override;
 
      template<poly_float(*tick)(poly_float, Memory*, OnePoleFilter<>&, OnePoleFilter<>&,
                                 poly_float, poly_float, poly_float, poly_float,
                                 poly_float, poly_float, poly_float)>
      void processFilter(int num_samples);
 
      void reset(poly_mask reset_mask) override;
 
      void hardReset() override;
 
      poly_float getDrive() { return scale_; }
 
      poly_float getResonance() { return feedback_; }
 
      poly_float getLowAmount() { return low_gain_; }
 
      poly_float getHighAmount() { return high_gain_; }
 
      poly_float getFilterMidiCutoff() { return filter_midi_cutoff_; }
 
      poly_float getFilter2MidiCutoff() { return filter2_midi_cutoff_; }
 
    protected:
      std::unique_ptr<Memory> memory_;
 
      FeedbackStyle feedback_style_;
 
      poly_float max_period_;
 
      poly_float feedback_;
 
      poly_float filter_coefficient_;
 
      poly_float filter2_coefficient_;
 
      poly_float low_gain_;
 
      poly_float high_gain_;
 
      poly_float scale_;
 
      poly_float filter_midi_cutoff_;
 
      poly_float filter2_midi_cutoff_;
 
      OnePoleFilter<> feedback_filter_;
 
      OnePoleFilter<> feedback_filter2_;
 
      JUCE_LEAK_DETECTOR(CombFilter)
  };
} // namespace vital