The laplace based contraction algorithm used here is basically a clone of this repo: https://github.com/taiya/cloudcontr
Check the README inside the tree_simulation folder for instructions to run the code. The matlab objects mega_cloud_lab_new_2.mat and mega_cloud_lab_complex_no_holes_4.mat are provided as a sample for testing. They correspond to the point clouds mega_cloud_lab_new_2.pcd and mega_cloud_lab_complex_no_holes.pcd, respectively.