Realistic Picture Group

“Propelled” – creative underwater simulation

Case Study

Loud Life Productions / Bank of Central Florida

We recently teamed up with Loud Life Productions to assist with their “Propelled” spot for the Bank of Central Florida.

This project presented some fun and interesting challenges. The majority of our responsibility was to create from scratch a believable looking propeller and underwater fluid simulation.

 

The propeller

It should be noted that the central “propeller” is designed based on Bank of Central Florida’s logo. It was very important to the director’s vision that the propeller we see in the underwater shot match this logo exactly. It was therefore necessary to build a custom 3D model of the propeller that would transition the shots seamlessly. The propeller was modeled based on references of real propellers, but the proportions were ultimately defined by modeling the surfaces directly over the logo.

The bubbles

Possibly the most challenging part of this shot was creating believable bubbles. This process underwent extensive revision. We tried many different approaches, but in the end, we got the best results by generating trailing geometry from the blades of the propeller. This geometry was then fed into a Pyro solver, and art directed further in Houdini’s Dynamics environment. More points were scattered into the resulting fields and further advected with multiple layers of noise.

Spheres were copied to these points, and became the basic bubble mesh. These spheres were then modified further with more noise, converted to volumes to blur them together, remeshed back into polygons, and finally rendered. Finding the right values for all these steps was a long process and required lots of revision, but in the end we were happy with the results.

Using these techniques, we created several layers of bubbles and volumes representing water disturbance and silt. All these elements were rendered out separately using Redshift and finally brought into Adobe After Effects for a final composite.

Conclusion

There are few things in our world that exhibit such complex and interesting behaviors as fluids. Thanks to the procedural nature of Houdini, we were able to attack this challenge in circular passes, starting rough and gradually honing in on believable and dynamic motion.

Staying organized and maintaining clear communication with the director and camera crew was also extremely important. 3D CG gives us a great deal of flexibility and control, but it is always best for these advantages to be applied with a clear plan of action. Coordinating with everyone at Loud Life Productions was easy and enjoyable.

We are excited to have had this opportunity to leverage 3D animation in these unique ways. Because of the strict requirements that the propeller match both the logo and the drawing on the board, it is safe to say that these shots could not have been created using traditional methods. We love to solve these kinds of unique problems and are excited to see what future challenges the Loud Life team can throw at us.

You can see the full Propelled spot here: