Level set advection

Hi guys,
I focused on model evolution by using levelsetadvect tool, does anyone know how to add different velocity for every voxels by VelocityFields, which really confused me a lot.
Thank you in advance.

The issue names the levelsetadvect tool and VelocityFields, but no source file or test. Start by locating those entry points and clarifying the intended per-voxel velocity input; done should be a documented, reproducible advection example or test.

Written by the indexing model from the issue text.