Example: idx_map: 1 1 1 1 2 3 2 2 1 2 3 2 1 1 2 3

plane_param: 4 (ax + by + cz + d) transform_map: [A, B, C] for {x, y, z} --> x = A * depth, y = B * depth, z = C * depth

plane_param: 4 (ax + by + cz + d) point to plane: d = |ax + by + cz + d| / sqrt(a**2 + b**2 + c**2) output: resid

Given point sets x1 and x2, transfers attributes attr1 from x1 to x2. idx1: N2 array containing the nearest neighbors indices of x2 in x1 idx2

feature extractor

Example: idx_map: 1 1 1 1 2 3 2 2 1 2 3 2 1 1

Uses iterative furthest point sampling to select a set of npoint features that have the largest minimum distance :param ctx: