Hilbert sort on the sphere
Copyright: The CGAL Project
Source: https://doc.cgal.org/latest/Spatial_sorting/HilbertOnSphereIllustration.png
Documentation: https://doc.cgal.org/latest/Spatial_sorting/index.html
Documentation authors: Christophe Delage and Olivier Devillers.
License: Creative Commons Attribution-NonCommercial-NoDerivs 2.0 Generic
https://creativecommons.org/licenses/by-nc-nd/2.0/
Reproduced without modification. No endorsement by CGAL is implied.

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