Quick test to change the viscosity of a flip fluid by particle age.

A point attribute called birthframe is made in Sops so that each particle knows when it was born. Then in Dops a Popvop is used to read the birthframe attribute, and subtract it from the current frame of the sim which gives the particle’s age. This age is then passed to a fit range node which fits the value of 0 to 40, to 0 to 5000. This is the value written to the viscosity attribute on each frame.


This is what the flip section of dops looks like. The popvop is placed after the source volume for the flip fluid.