Character & Effects Work

Wind Setup:

I had the opportunity to develop a tornado simulation system for the character Pepa. Pepa has the power to control the weather, the movie called for this stylized effect in the moments where she is anxious.

As show in the video breakdown, I wrote a field generator using a proprietary Disney scripting language, similar to C++, in order to give control to artists for the directionality and “emotion” of the tornado. Incorporating camera based manipulation was key to the simulation system modification that I made, as silhouettes are a major part of Disney’s design language.

I worked on multiple vellum based setups for one-off shots during my time at DreamWorks—including the blanket simulation show in Figure 1a. I helped develop Houdini workflow as it was not in the studio pipeline. Vellum is a simulation framework that uses an extended Position Based Dynamics approach. It can be used to create many different things including cloth, hair, tetrahedral softbodies, balloons, and grains. The main advantage of a Position Based Approach (PBA) is its controllability, stability, and ability to produce believable results quickly.

Another main advantage to these setups is that different dynamics such as Fur, Hair, and Cloth simulate in the same network. Since a PBA system allows for a multitude of configurations, the possibilities are endless for the combination of dynamic system types that can interact with each other.

Eden Geotech is developing innovative geotechnical solutions for a sustainable energy future. I had the pleasure of working on a looping animation for their website to abstractly represent their model for a renewable & self-sustaining system.

The viewport [Figure 1b] pass of the Fluid, Pyro (smoke), Lightning, & Destruction Simulations shows a GL render of the effects. The key challenges for these series of effects was making sure that all the components of the effect worked together in one space but also didn’t require re-simulation of the whole system to change one dynamics component. This was achieved by creating references to collision geometry and volumes in each partitioned simulation network. These systems could run in parallel.

The other challenge was maintaining the texture [Figure 2b] and UV mapping across different topologies as the center geometry takes on three different stages: magma, solid rock, and fragmented rock. In order to achieve this, I created a high density mesh for the solid rock that would be wrapped to the magma at the same point and vertex count. This also allowed for the transformation from these two states, which I drove with a noise map. To match the shading context between the solid and fragmented parts, I sampled the nearest point of the two components and used that as the UV value, and for the interior of the fragmented pieces, used a local space UV mapping as it got its own shader.