X-Particles Rippling Particle Radius

May 27th 2019 08:00:06am

This week I made a video tutorial that focuses on some particle manipulation. Specifically manipulation that will ripple the particle radius. So what do I mean by rippling the particle radius? We are basically going to setup a system of base particles on a geometry surface. Those particles will then be triggered by a set of secondary particles that will move across the same surface. These secondary particles will collide (secretly behind the scenes) with the base particles as they move. Then we will have the particle radius of the base particles ripple by scaling them up and then back down.

The Effect
This rippling of the particle radius up then down will give us this undulating motion. Once some basic geometry has been attached to the particles, the particle radius will drive the geometry. This video shows the effect in motion.

While the video shows a flat surface, you can easily use curved geometry surfaces to run the effect on. This core particle radius rippling concept allows for a variety of looks. Just by changing the surface geometry we emit from as well as the visible geometry we attach to the particles, we can alter the final look.

Samples

Here are just a few samples of possible shapes and surfaces that could be used.

ripple particle radius
ripple particle radius

Checkout more:
Relative Paths with X-Particles Caches
Free Function Friday Ep.12 – findCompByName
Houdini | Velocity Forces
Houdini | Surface Advection
Houdini | Liquid SOPs