WhiteNoise.h

// WhiteNoise.h
// ofxPDSP
// Nicola Pisanti, MIT License, 2016


#ifndef PDSP_RANDOM_PRNOISEGEN_H_INCLUDED
#define PDSP_RANDOM_PRNOISEGEN_H_INCLUDED

#include <time.h>
#include "../pdspCore.h"


#ifdef _MSC_VER
#pragma warning( push )
#pragma warning( disable : C4838)
#pragma warning( disable : C4554)
#endif

#ifdef __GNUC__
    #pragma GCC diagnostic push
    #pragma GCC diagnostic ignored "-Wparentheses"
#endif


#define EXTRACT_BITS(the_val , bits_start , bits_len) ((the_val >> (bits_start-1)) & ((1<<bits_len-1)))

namespace pdsp{

static const float PNDivisor = 1.0 / 268435456.0; // 1/(2^32 / 16 )


inline_f float PNSequenceNext(uint32_t& PNRegister){
    //get the bits
    uint32_t b0  = EXTRACT_BITS(PNRegister, 1, 1); //1 = b0
    uint32_t b1  = EXTRACT_BITS(PNRegister, 2, 1); //2 = b1
    uint32_t b27 = EXTRACT_BITS(PNRegister, 28, 1); //28 = b27
    uint32_t b28 = EXTRACT_BITS(PNRegister, 29, 1); //29 = b28

    //form the XOR
    uint32_t b31 = b0^b1^b27^b28;

    //form the mask to OR with the register to load b31 
    if (b31 == 1){
            b31 = 0x10000000;
    }

    PNRegister >>= 1;
    PNRegister |= b31;

    return ((PNRegister * PNDivisor) - 1.0);

}

class WhiteNoise : public Unit{
public:
    WhiteNoise();

    Patchable& in_clock();
    
    Patchable& in_reseed();
    
    Patchable& out_signal();
    
private:
    void prepareUnit( int expectedBufferSize, double sampleRate ) override;
    void releaseResources() override;

    void process(int bufferSize) noexcept override;
    void process_run(const int &bufferSize) noexcept;
    void process_PA(const float* &trigSyncBuffer, const int &bufferSize) noexcept;
    void process_SA_TA(const float* &trigSyncBuffer, const float* &trigSeedBuffer, const int &bufferSize) noexcept;
            
    inline_f void reSeed();
    
    OutputNode output;
    InputNode input_trig_clock;
    InputNode input_trig_seed;
    
    uint32_t seed;
    uint32_t seedMult;
    uint32_t pnRegister;
    
};

}


#ifdef _MSC_VER
#pragma warning( pop ) 
#endif

#ifdef __GNUC__
    #pragma GCC diagnostic pop
#endif


#endif  // PDSP_RANDOM_PRNOISEGEN_H_INCLUDED