Katy Perry in de jungle (ENG)
The tiger roar shot was a bit more complicated. To create the fireflies that buzz around the environment and then gravitate towards the center to the tiger’s head, a combination of X-Particles and Thinking Particles was used. X-Particles was faster to set up: only a volume emitter, an attractor and a few deflectors were needed to guide the fireflies to the center in a natural manner. Once the fireflies reached the center, they were killed off and Thinking Particles was used to emit from pre-rendered tiger footage to drive the firefly birth and color. Varying the intensity and direction in Thinking Particles made the roar very expressive and magical. After Effects was then used to add color and glow to the fireflies as well as add their reflections in the water.
CINEMA 4D was also used to help test techniques for the effect that called for a swarm of fireflies to gather and take the shape of a roaring tiger head. Once they’d come up with a plan, the Mirada team rigged the model in Maya using a combination of skinning and corrective shapes. When the animation was complete, the geometry was baked with Alembic and imported into Houdini for the articulate particle effects.
“The motion of the tiger roaring needed to be carefully considered as it would be the basis of the particles’ movement and determine the overall clarity of the image the swarm was meant to produce,” Shelton explains, adding that it was also important that the tiger have a regal feel to it. He also wanted the point of the actual roar to be in sync with the lyrics of the song. So combining the moving camera and the finite number of frames they had to work with when the tiger entered the frame was critical. “Luckily, the Mirada pipeline from Maya to Houdini made iterating between Houdini very quick,” he says.
After the tiger head had been animated in Maya and imported into Houdini, Mirada FX artists were able to scatter points on the tiger head and use them as attractor points for the particles, making the same number of points on the tiger as in the air. A custom tool was written to make the particles attract to the points and then release at a specified time. Houdini was able to control the brightness of each particle based on the Fresnel angle of the tiger to the camera.
Telling Great Stories
Mirada’s main goal, Wu says, is to tell good stories whether they’re working on a music video, film, commercial or interactive project. And having the opportunity to work on something as high profile as “Roar,” was fantastic.
Both the song and the video have been widely publicized and praised, and the Mirada team is already hard at work on other projects. Wu is busy developing German author Cornelia Funke’s latest interactive storybook, while Shelton is currently leading a three-minute photo-real CG project. Reflecting on the “Roar” video, Wu describes the project as “a great experience for the entire team with great energy and all-around good vibes.”
Website Mirada: http://mirada.com/
Website Motion Theory: http://www.motiontheory.com/