Inconsistent convolution result between WarpConvNet and MinkowskiEngine

[Xiashangning]

Hi, thanks for open-sourcing yet another sparse pytorch library, excellent job!

However, when I comparing the results from SparseConv3d with that from MinkowskiConvolution, I found that even if the input and their weight/bias are strictly equal, their outputs are very different.

Therefore, I would like to know if there are any difference in the implementation of the sparse 3d convolution algorithm.

Besides, it seems that SparseConv3d is much slower than MinkowskiConvolution, with 120% more computational time used. Is this expected? How can we improve the speed of WarpConvNet?

Thanks,