Façade: image-based set replacement on Big Hero 6

The visual complexity and production demands of Big Hero 6 required an approach to digital set replacement that was efficient to render while maintaining the original visual fidelity of the shot. Moreover, that visual fidelity had to be maintained under stereoscopic viewing and camera motion. This technique, named Facade, was used to recreate sets ranging from garage interiors to the cityscapes of the film's fictional San Fransokyo. Facade replaced arbitrarily complex geometry with a finite polygonal mesh that emitted pre-baked lighting back into the scene like any other light source in a global illumination (GI) renderer. Additionally, Facade was able to replace the visible background geometry entirely for certain shots, leading to further performance gains. The end result was a significant per-frame performance gain versus rendering the full background for each frame in a given shot.