PIPELINE TECHNIQUES: Simulate Particle Advection In houdini
Make amazing particle sims
houdini has been taking the FX world by storm for some time now, and if you’ve been looking for an opportunity to branch out and become an FX wizard there is no better time than now to get started. since the release of houdini 16.5 the software from the team at sidefx has never been more accessible and user friendly especially for first time users.
in this tutorial we will learn a simple yet effective technique for creating amazing particle simulations using houdini Pyro as an advection source to create ethereal flowing particle caches.
using a simple Pyro DOP network we can drive the emission, force and velocity of a POP sim and create this amazing effect in less than ten nodes!
Source your Pyro Before we can create our particle simulation we must first create our Pyro advection source. We will begin by creating an object source to drive our Pyro simulation. start by ctrl-clicking on the sphere in the create shelf at the top left of your screen, and then attaching a Billowy smoke node from the Pyro shelf.
Pyro source node tree Most of the default Pyro nodes will be all we need to get started. in this setup you will have a source Volume, a smoke Object, a Resize container, a Pyro solver and i also like to add a Gas Turbulence node attached to the Velocity update input number three. This will provide us with a great base to start with that is easy to manipulate with fast results as long as you keep your cell division size reasonably low in the smoke Object node.
Pyro solver settings in our Pyro solver we want to focus on the simulation and shape tabs. under simulation you will want to increase your Timescale to 2, and to lower the default Diffusion and cooling Rates so that your Pyro smoke will have enough upward momentum and not just linger close to the source. it is also important to increase your buoyancy to something like 10. under the shape tab, you will want to dramatically reduce the Dissipation so that the smoke lives long enough to drive our particle simulation, and be sure to add Disturbance, shredding and Turbulence to give it life.