spconv ... sparse convolution

[dorn-gerhard]

Motivation and description

For many applications (graph neural networks, 3d point clouds, ...) sparse convolution would be a cool feature

Possible Implementation

A guide to implementation is given here (with some references):
https://towardsdatascience.com/how-does-sparse-convolution-work-3257a0a8fd1

[ToucheSir]

I doubt anyone is going to step up to write custom CUDA kernels for this like in that post unless they also need the feature, so it's in solid "PRs welcome" status for now. You may want to see if anything in GeometricFlux, GraphNeuralNetworks.jl or Flux3D helps with your use case. Those three should cover GNNs and point clouds between them.