Resource.h

#pragma once
#include <map>
#include <vector>

class Resource {
public:
    virtual ~Resource() {}

    virtual void *getBuffer() const = 0;

    virtual size_t size() const = 0;
};

class CudaBuffer : public Resource {
public:
    CudaBuffer(void *buffer = nullptr, size_t size = 0)
        : _buffer(buffer), _ownBuffer(false), _size(size) {}
    CudaBuffer(size_t size) : _buffer(nullptr), _ownBuffer(true), _size(size) {
        CHECK_EX(cudaMalloc(&_buffer, size));
    }
    CudaBuffer(const CudaBuffer &rhs) = delete;

    virtual ~CudaBuffer() {
        if (!_ownBuffer || _buffer == nullptr)
            return;
        try {
            CHECK_EX(cudaFree(_buffer));
        } catch (std::exception &ex) {
            Logger::instance.warning(std::string("Exception raised in destructor: ") + ex.what());
        }
        _buffer = nullptr;
        _ownBuffer = false;
    }

    virtual void *getBuffer() const { return _buffer; }
    template <class T> T *getBuffer() const { return (T *)getBuffer(); }

    virtual size_t size() const { return _size; }

private:
    void *_buffer;
    bool _ownBuffer;
    size_t _size;
};

template <typename T> class CudaArray : public CudaBuffer {
public:
    CudaArray(size_t n) : CudaBuffer(n * sizeof(T)) {}
    CudaArray(T *buffer, size_t n) : CudaBuffer(buffer, n * sizeof(T)) {}
    CudaArray(const std::vector<T> &hostArray) : CudaBuffer(hostArray.size() * sizeof(T)) {
        cudaMemcpy(getBuffer(), hostArray.data(), size(), cudaMemcpyHostToDevice);
    }
    CudaArray(const CudaArray<T> &rhs) = delete;

    size_t n() const { return size() / sizeof(T); }

    operator T *() { return (T *)getBuffer(); }
    CudaArray<T> *subArray(size_t offset, size_t n = -1) {
        if (n == -1)
            n = this->n() - offset;
        return new CudaArray<T>(*this + offset, n);
    }
};

class GraphicsResource : public Resource {
public:
    cudaGraphicsResource_t getHandler() { return _res; }

    virtual ~GraphicsResource() {
        if (_res == nullptr)
            return;
        try {
            CHECK_EX(cudaGraphicsUnregisterResource(_res));
        } catch (std::exception &ex) {
            Logger::instance.warning(std::string("Exception raised in destructor: ") + ex.what());
        }
        _res = nullptr;
    }

    virtual size_t size() const { return _size; }

protected:
    cudaGraphicsResource_t _res;
    size_t _size;

    GraphicsResource() : _res(nullptr), _size(0) {}
};

template <typename T> class GlTextureResource : public GraphicsResource {
public:
    GlTextureResource(GLuint textureID, glm::uvec2 textureSize) {
        CHECK_EX(cudaGraphicsGLRegisterImage(&_res, textureID, GL_TEXTURE_2D,
                                             cudaGraphicsRegisterFlagsWriteDiscard));
        _size = textureSize.x * textureSize.y * sizeof(T);
        _textureSize = textureSize;
    }

    virtual ~GlTextureResource() { cudaGraphicsUnmapResources(1, &_res, 0); }

    virtual void *getBuffer() const {
        cudaArray_t buffer;
        try {
            CHECK_EX(cudaGraphicsSubResourceGetMappedArray(&buffer, _res, 0, 0));
        } catch (...) {
            return nullptr;
        }
        return buffer;
    }

    operator T *() { return (T *)getBuffer(); }

    glm::uvec2 textureSize() { return _textureSize; }

private:
    glm::uvec2 _textureSize;
};

class Resources {
public:
    std::map<std::string, Resource *> resources;
    std::vector<cudaGraphicsResource_t> graphicsResources;

    void addResource(const std::string &name, Resource *res) {
        auto gres = dynamic_cast<GraphicsResource *>(res);
        if (gres != nullptr)
            graphicsResources.push_back(gres->getHandler());
        resources[name] = res;
    }

    void clear() {
        resources.clear();
        graphicsResources.clear();
    }
};

template <typename T, typename T2 = T>
void dumpArray(std::ostream &so, CudaArray<T> &arr, size_t maxDumpRows = 0,
               size_t elemsPerRow = 1) {
    int chns = sizeof(T) / sizeof(T2);
    T2 *hostArr = new T2[arr.n() * chns];
    cudaMemcpy(hostArr, arr.getBuffer(), arr.n() * sizeof(T), cudaMemcpyDeviceToHost);
    dumpHostBuffer<T2>(so, hostArr, arr.n() * sizeof(T), chns * elemsPerRow, maxDumpRows);
    delete[] hostArr;
}