Load / Save KDTreeFlan pcd_tree = o3d.geometry.KDTreeFlann(pcd)

[tchaton]

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Hey,

It will be great to have a way to serialize the KDTree built by Flann to pickle file and be able to reload this KDTree for later use.

Especially for DL training, we don't want to lose time re-calculating the KDTree every time the pointcloud is loaded.

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[tchaton]

The code from the binding is just there: https://github.com/jlblancoc/nanoflann/blob/master/examples/saveload_example.cpp