The Path Tracer also opened up more realistic looks and expressions in the characters, which not only brought more power to the performances, but also removed a classic sticking point for digital humans. “How a character looks and the emotions you’re getting across from the face has everything to do with how you light it,” notes Adam. “Sometimes we would do all of this work and realize we had to go back and change something after seeing the path-traced render. It really refined what we were doing and gave us just a little bit more.”
To create those characters, Adam and his team decided to accelerate the process by adopting the MetaHuman standards for facial rigs, an idea they had seen online. Since their character designs were already locked, they began by porting the fairy-like facial topologies over to Epic. Epic then sent back the calibrated MetaHuman rigs that incorporated the designs, giving the short all the emotions it needed.
“As an animation person, you learn the language of faces and emotions. The accuracy is not just about how the skin moves, but whether you can achieve emotional clarity,” says Adam. “Those rigs are very good at that. So you’re not just getting some small details, you’re getting a relatable, expressive face, which is kind of everything for your main characters.”
Source: Unreal Engine Blog