Visualization code for point splittings

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The file vis_splitting.py contains code for visualizing point splitting paths. There are three import functions to use:

1. splitting_paths

splitting_paths(pcd1, 
                pcd2, 
                inds=None, 
                colors_points=colors_points, 
                colors_paths=colors_path2)

this function is for visualizing splitting paths between two point clouds, pcd2 should split from pcd1, and 'inds' is a list of point indices to visualize. The function will return an open3d mesh object of pcd1 and the specific splitting paths.

2. splitting_paths_triple

splitting_paths_triple(pcd1, 
                       pcd2, 
                       pcd3, 
                       inds=None, 
                       colors_points=colors_points, 
                       colors_path1=colors_path1,
                       colors_path2=colors_path2)

this function is for visualizing two steps splitting for points specified in 'inds'.

3. splittings_by_range

splittings_by_range(pcd1, 
                    pcd2, 
                    pcd3,
                    range_x=(0, 0.5),
                    range_y=(0, 0.1),
                    range_z=(0, 0.5))

this function is for visualizing two steps splitting for points specified by ranges. If you want to visualize points of a small area in 3D space and don't know the exact point indices, this function will help you. Ranges are determined by the visualization boundary on each axis (i.e. range_x, range_y, range_z), and ranges should be within [0, 1].

Visualizing and saving mesh object.

All the above three functions return open3d mesh object, use

open3d.visualization.draw_geometries([mesh])

to save mesh object, use

o3d.io.write_triangle_mesh(filename, mesh)