I working attempting to create some interesting swirls using velocity fields. So far I've managed to isolate the fields and create some nice starting points, but I'm struggling with the complex next step of converting the flow lines into more general features, hopefully the image below can illustrate a bit.

What I currently have is the red flow lines (you can disregard the white plane behind) and I am hoping to convert them into something similar to the green lines I've drawn.



Thanks a lot!

You could try scattering points inside your field, and then using a Solver SOP to advect them through your field. You can then use a Trail SOP to trace the the path of your points over time.

How did you create this? There are many ways to do this. Post your file……..