Question about PillarLayer

[wojtat]

Hi, I have a question about the PillarLayer module. I was under the impression that the PointPillars algorithm is supposed to first group the input points into pillars, that is a 2D grid. But it looks like the PillarLayer and Voxelization code groups the points into a 3D grid. Could you explain more how this works, or if the voxels are later somewhere converted into pillars?

Thanks in advance!