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At SIGGRAPH 2023, we attended a session named Crowded House: Advances in Crowd Simulation about three impressive projects using various techniques.
I Wanna Dance With Somebody: volumetric and authentic crowds
First of all, Dimension Studio, Zero VFX, and Redefine explained us how they used volumetric video to generate authentic crowds. After an introduction about their latest challenges, such as their work on Bohemian Rhapsody, the biopic on Freddie Mercury and Queen, shared their work on another biopic: Whitney Houston: I Wanna Dance With Somebody.
The movie features concerts taking place over a 40-year period, with crowds upwards of 70,000 people. The team relied on a novel approach to manage these crowds: instead of simulating them in 3D or using 2D elements filmed in front of a green screen, volumetric video has been used. Each extra was captured in 3D. In total, nearly 300 individuals were filmed this way, with 1,000 captures in 2K and 4K. The sessions were conducted with various costumes and hairstyles, since the movie depicts concerts taking place during different eras.
This volumetric approach has the advantage of providing highly realistic extras with nuanced performances that can be used in close-up shots without constraints on the viewing angle. For more information, you can check out an interview about this project over at Before & Afters. A VFX breakdown is also available below.
We should also highlight that we already discussed volumetric capture in our SIGGRAPH 2023 coverage, with the launch of Holosys+.
Pixar unveils the secrets of Elemental
Next, Pixar took the stage and shared their work on Elemental. The animated feature is teeming with with fire, air, earth and water characters. To give life to this world, the team chose to create a Houdini Engine character pipeline based on blended simulation caches. They also had to improve their character pipeline in order to to approximate non-skeletal deformation with blendshapes. Thanks to these new features, the team was able to animate, deform and render an massive amount of voxels.
For more information, a paper by Pixar is available.
Strange World: creating creature chaos
Last, but not least, Disney showcased the methods that brought crowds to the forefront of their animated feature Strange World. The team showcased their new in-house tools for crowd management, along with pipeline optimizations: it’s worth mentioning that with 65 million crowds elements, both in the background and in the foreground, this task was daunting.
