hvirtual/plugins/freeverb/Components/allpass.hpp

   1 // Allpass filter 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 _allpass_
   8 #define _allpass_
   9 #include "denormals.h"
  10
  11 class allpass
  12 {
  13 public:
  14                                         allpass();
  15                         void    setbuffer(float *buf, int size);
  16         inline  float   process(float inp);
  17                         void    mute();
  18                         void    setfeedback(float val);
  19                         float   getfeedback();
  20 // private:
  21         float   feedback;
  22         float   *buffer;
  23         int             bufsize;
  24         int             bufidx;
  25 };
  26
  27
  28 // Big to inline - but crucial for speed
  29
  30 inline float allpass::process(float input)
  31 {
  32         float output;
  33         float bufout;
  34
  35         bufout = buffer[bufidx];
  36         undenormalise(bufout);
  37
  38         output = -input + bufout;
  39         buffer[bufidx] = input + (bufout*feedback);
  40
  41         if(++bufidx>=bufsize) bufidx = 0;
  42
  43         return output;
  44 }
  45
  46 #endif//_allpass
  47
  48 //ends
  49
  50
  51
  52
  53