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 * modification, are permitted provided that the following conditions
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 *  * Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *  * Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
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 *    contributors may be used to endorse or promote products derived
 *    from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS ``AS IS'' AND ANY
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#ifndef __BODYSYSTEMCUDA_H__
#define __BODYSYSTEMCUDA_H__

#include "bodysystem.h"

template <typename T> struct DeviceData
{
    T           *dPos[2]; // mapped host pointers
    T           *dVel;
    cudaEvent_t  event;
    unsigned int offset;
    unsigned int numBodies;
};

// CUDA BodySystem: runs on the GPU
template <typename T> class BodySystemCUDA : public BodySystem<T>
{
public:
    BodySystemCUDA(unsigned int numBodies,
                   unsigned int numDevices,
                   unsigned int blockSize,
                   bool         usePBO,
                   bool         useSysMem = false,
                   bool         useP2P    = true,
                   int          deviceId  = 0);
    virtual ~BodySystemCUDA();

    virtual void loadTipsyFile(const std::string &filename);

    virtual void update(T deltaTime);

    virtual void setSoftening(T softening);
    virtual void setDamping(T damping);

    virtual T   *getArray(BodyArray array);
    virtual void setArray(BodyArray array, const T *data);

    virtual unsigned int getCurrentReadBuffer() const { return m_pbo[m_currentRead]; }

    virtual unsigned int getNumBodies() const { return m_numBodies; }

protected: // methods
    BodySystemCUDA() {}

    virtual void _initialize(int numBodies);
    virtual void _finalize();

protected: // data
    unsigned int m_numBodies;
    unsigned int m_numDevices;
    bool         m_bInitialized;
    int          m_devID;

    // Host data
    T *m_hPos[2];
    T *m_hVel;

    DeviceData<T> *m_deviceData;

    bool         m_bUsePBO;
    bool         m_bUseSysMem;
    bool         m_bUseP2P;
    unsigned int m_SMVersion;

    T m_damping;

    unsigned int          m_pbo[2];
    cudaGraphicsResource *m_pGRes[2];
    unsigned int          m_currentRead;
    unsigned int          m_currentWrite;

    unsigned int m_blockSize;
};

#include "bodysystemcuda_impl.h"

#endif // __BODYSYSTEMCUDA_H__
