d z

Hey looking for a solution to render out the motion vectors for of a volumetric smoke simulation.
something similar like a flow map..

i want to do this
http://www.klemenlozar.com/frame-blending-with-motion-vectors/ [www.klemenlozar.com]

is there ans efficient way to do this?
i am a technical artist so if i have to set it up by hand ok but i could bet there is already a nice node for this..

i mean i just have to compare the current and last frame of the voxels/ particles and apply a color in which direction the particle moved so it cant be to hard..
but i am not quiet sure how to do this in houdini