I'm working in Houdini, but it's a more general transform problem, maybe there's a proper math term for it. On the left is the initial state. I have a bunch of points. I used different colors to differentiate them (disregard the white point A for now). These points undergo a slight non-uniform transform and move a bit to new positions, as shown on the right. On the left, I also have an independent point A, in white. I want to compute where its new location should be (A' on the right) given the interpolated influence and distance to the transformed guide points (color). There will be parameters deciding the strength of the influence, distance, etc but it's a minor problem. It's not a fluid sim, but it seems similar cases exist for fluid sims, if you want to add more points for detail, and have them be guided by the more-sparse, pre-computed sim points. Another concept that could be related is opti-flow. I could iterate in vex, but I'm 99% sure that in Houdini there's already a SOP that does this.

Have you tried the point deform sop?

Cheers
CYTE

Not yet, I'll give it a try. Thanks.