[Paraview] extract voriticy and follow it in time

[Ufuk Utku Turuncoglu (BE)]

Hi,

I would like to use Threshold filter for Vorticity field calculated by 
ComputeDreivatives but in the variables list i could not see Vorticity 
field. So, is it possible to do it with any other way such as 
programmable filter etc. If i extract it from the whole data, then, i 
would like to follow it to create polyline that represent path of the 
selected region. So, is there any simple way to do that?

Best Regards,

--ufuk