Descriptions of generated streamtracer attributes

Hi all,

When integrating a streamline the streamtracer generates attributes angular velocity, rotation, and vorticity. Are there any documented descriptions of these attributes or how they are derived?

Thanks,
Sam

https://vtk.org/doc/nightly/html/classvtkStreamTracer.html
https://gitlab.kitware.com/vtk/vtk/-/blob/master/Filters/FlowPaths/vtkStreamTracer.cxx