Guided recording

A gesture pushes the fluid, changing its momentum, and adds passive dye: ink carried by the flow. Releasing ends that input; the velocity field continues to evolve. The ink marks motion without pushing the flow itself.

Will releasing the gesture stop the flow immediately?

Periodic square: material leaving one edge returns at the opposite edge. This is not a closed tank.

Shared starting setup

Coasting vortex · 128² · νA = 0.002

Recording transcript

The recording covers Make a Flow and Keep the Swirl. The other chapters below are text guides, not recorded results for those setups.

First, Make a Flow shows passive ink carried by a 2D velocity field. Then Keep the Swirl copies the complete starting state into A and B and changes only B’s viscosity. Both copies advance at the same model time. Playback ends paused; the recorded values belong to that run, not to your device. Surface depth is a visual encoding of ink concentration, not a third physical dimension.