Function lambert_bwd

model/render/renderutils/c_src/torch_bindings.cpp:268–290

}

std::tuple<torch::Tensor, torch::Tensor> lambert_bwd(torch::Tensor nrm, torch::Tensor wi, torch::Tensor grad)
{
    cudaStream_t stream = at::cuda::getCurrentCUDAStream();

    // Extract input parameters.
    LambertKernelParams p;
    update_grid(p.gridSize, nrm, wi);

    // Choose launch parameters.
    dim3 blockSize = getLaunchBlockSize(BLOCK_X, BLOCK_Y, p.gridSize);
    dim3 gridSize = getLaunchGridSize(blockSize, p.gridSize);

    torch::Tensor nrm_grad, wi_grad;
    p.nrm = make_cuda_tensor(nrm, p.gridSize, &nrm_grad);
    p.wi = make_cuda_tensor(wi, p.gridSize, &wi_grad);
    p.out = make_cuda_tensor(grad, p.gridSize);

    // Launch CUDA kernel.
    void* args[] = { &p };
    NVDR_CHECK_CUDA_ERROR(cudaLaunchKernel((const void*)LambertBwdKernel, gridSize, blockSize, args, 0, stream));

    return std::tuple<torch::Tensor, torch::Tensor>(nrm_grad, wi_grad);
}

//------------------------------------------------------------------------
// frostbite diffuse