granularplayer.h

/*
Copyright (c) 2020 Electrosmith, Corp, Vinícius Fernandes
 
Use of this source code is governed by an MIT-style
license that can be found in the LICENSE file or at
https://opensource.org/licenses/MIT.
*/
 
#pragma once
#ifndef DSY_GRANULARPLAYER_H
#define DSY_GRANULARPLAYER_H
 
#include <stdint.h>
#include <cmath>
#include "Control/phasor.h"
#ifdef __cplusplus
#ifndef M_PI
#define M_PI 3.14159265358979323846 /* pi */
#endif
 
namespace daisysp
{
class GranularPlayer
{
  public:
    GranularPlayer() {}
    ~GranularPlayer() {}
 
    void Init(float* sample, int size, float sample_rate);
 
    float Process(float speed, float transposition, float grain_size);
 
  private:
    //Wraps an index to the size of the sample array
    uint32_t WrapIdx(uint32_t idx, uint32_t size);
 
    //Converts cents(1/100th of a semitone) to a ratio
    float CentsToRatio(float cents);
 
    //Converts milliseconds to  number of samples
    float MsToSamps(float ms, float samplerate);
 
    //Inverts the phase of the phasor if the frequency is negative, mimicking pure data's phasor~ object
    float NegativeInvert(Phasor* phs, float frequency);
 
 
    float* sample_;        //pointer to the sample to be played
    float  sample_rate_;   //audio engine sample rate
    int    size_;          //number of elements in the sample array
    float  grain_size_;    //grain size in milliseconds
    float  speed_;         //processed playback speed.
    float  transposition_; //processed transpotion.
    float  sample_frequency_;
    float  cosEnv_[256] = {0}; //cosine envelope for crossfading between grains
    float
        idxTransp_; // Adjusted Transposition value contribution to idx of first grain
    float
          idxTransp2_; // Adjusted Transposition value contribution to idx of second grain
    float idxSpeed_; // Adjusted Speed value contribution to idx of first grain
    float
          idxSpeed2_; // Adjusted Speed value contribution to idx of second grain
    float sig_;       // Output of first grain
    float sig2_;      // Output of second grain
 
    uint32_t idx_;  // Index of first grain
    uint32_t idx2_; // Index of second grain
 
    Phasor phs_;     // Phasor for speed
    Phasor phsImp_;  // Phasor for transposition
    Phasor phs2_;    // Phasor for speed
    Phasor phsImp2_; // Phasor for transposition
};
} // namespace daisysp
#endif
#endif