Function get_pixel

src/backend/cuda/kernel/orb.hpp:200–213

template<typename T>
inline __device__ T get_pixel(unsigned x, unsigned y, const float ori,
                              const unsigned size, const int dist_x,
                              const int dist_y, CParam<T> image,
                              const unsigned patch_size) {
    float ori_sin   = sin(ori);
    float ori_cos   = cos(ori);
    float patch_scl = (float)size / (float)patch_size;

    // Calculate point coordinates based on orientation and size
    x += round(dist_x * patch_scl * ori_cos - dist_y * patch_scl * ori_sin);
    y += round(dist_x * patch_scl * ori_sin + dist_y * patch_scl * ori_cos);

    return image.ptr[x * image.dims[0] + y];
}

inline __device__ int lookup(const int n, cudaTextureObject_t tex) {
    return tex1Dfetch<int>(tex, n);