Episode 21- Fabric Floaty Car-Dealership Tubes

Today, we’re talking about how to *Drummroll* MAKE FABRIC FLOAT-Y HOSES USING HOUDINI’S VELLUM. WHOOOOOOO! Did that help make this seemingly boring topic seem less boring? Yeah, ok. Moving right along past that.

So basically Vellum is Houdini’s newish toolset for creating cloth and fabric simulations that are very realistic. So really, this topic is actually pretty cool. I mean, come on, there’s SO MANY awesome applications for this. I actually can’t wait to learn more about this topic.

In classic Houdini fashion, this is one of those things that’s really simple conceptually, but can get complicated really fast. Ok so here’s the Cliff’s notes:

Step 1- Make some geometry to animate. In this tutorial (by an awesome YouTube channel called “Entagma”) we made tubes. So the idea was to make them like those dancing noodle tubes you see outside of car dealerships. Then we have to scatter points across the surface so that there are more points for the simulation to analyze and use for bending and deformation.

Step 2- Add in the Vellum Solver. This is essentially the “Brains” behind the simulation. We apply this directly to our geometry and… it just falls right down. So we have to change some settings in order to make the bottom points on our tubes “attach” to the ground, then change some constraints on the tubes themselves so that they have “struts” to give the tubes a but more structure and don’t just fall into themselves.

Step 3- Art-direct the simulation and movement of the wind affecting the tubes using the Vellum Solver. In this step, we’re making changes to the physics to take what we’ve made so far and make it all look not only physically correct, but also look nice in the shot itself. So, for example, maybe one of the tubes wasn’t being affected as much as the others and so it tended to lay down while the others stood up more tall. This could be correct physically, but not look the way we want it.

This is a balance that you have to strike while animating. Making something look correct and making it look good are often two different things, and it just takes practice and close attention to strike the right balance. Right now…let’s just say I’ll be working on practicing more.

Jake-out.