hvirtual/plugins/freeverb/Components/comb.hpp

   1 // Comb filter class declaration
   2 //
   3 // Written by Jezar at Dreampoint, June 2000
   4 // http://www.dreampoint.co.uk
   5 // This code is public domain
   6
   7 #ifndef _comb_
   8 #define _comb_
   9
  10 #include "denormals.h"
  11
  12 class comb
  13 {
  14 public:
  15                                         comb();
  16                         void    setbuffer(float *buf, int size);
  17         inline  float   process(float inp);
  18                         void    mute();
  19                         void    setdamp(float val);
  20                         float   getdamp();
  21                         void    setfeedback(float val);
  22                         float   getfeedback();
  23 private:
  24         float   feedback;
  25         float   filterstore;
  26         float   damp1;
  27         float   damp2;
  28         float   *buffer;
  29         int             bufsize;
  30         int             bufidx;
  31 };
  32
  33
  34 // Big to inline - but crucial for speed
  35
  36 inline float comb::process(float input)
  37 {
  38         float output;
  39
  40         output = buffer[bufidx];
  41         undenormalise(output);
  42
  43         filterstore = (output*damp2) + (filterstore*damp1);
  44         undenormalise(filterstore);
  45
  46         buffer[bufidx] = input + (filterstore*feedback);
  47
  48         if(++bufidx>=bufsize) bufidx = 0;
  49
  50         return output;
  51 }
  52
  53 #endif //_comb_
  54
  55 //ends
  56
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  60