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#include <curand.h>
#include <string>

// RNGs
class RNG
{
public:
    enum RngType { Pseudo, Quasi, ScrambledQuasi };
    RNG(unsigned long prngSeed, unsigned int qrngDimensions, unsigned int nSamples);
    virtual ~RNG();

    float getNextU01(void);
    void  getInfoString(std::string &msg);
    void  selectRng(RngType type);
    void  resetSeed(void);
    void  resetDimensions(void);
    void  incrementDimensions(void);

private:
    // Generators
    curandGenerator_t *m_pCurrent;
    curandGenerator_t  m_prng;
    curandGenerator_t  m_qrng;
    curandGenerator_t  m_sqrng;

    // Parameters
    unsigned long m_prngSeed;
    unsigned int  m_qrngDimensions;

    // Batches
    const unsigned int m_nSamplesBatchTarget;
    unsigned int       m_nSamplesBatchActual;
    unsigned int       m_nSamplesRemaining;
    void               generateBatch(void);

    // Helpers
    void updateDimensions(void);
    void setBatchSize(void);

    // Buffers
    float *m_h_samples;
    float *m_d_samples;

    static const unsigned int s_maxQrngDimensions;
};
