Traditional modeling uses motion-capture to recreate the movement of a real-world actor. The Mass Effect 2 technology moves beyond traditional performance-capture and relies on AI to generate a character's on-screen performance for the game's cinematic cut scenes.
"Once artists design the face of a human or alien character, we move directly to the script and voice recording," says Bioware senior producer Adrien Cho. "After the actor comes in and performs his or her lines in a variety of different emotional tones (angry, urgent, scared), vocal stress and inflection readers in the AI detect the emotional flags of the given line and alter the character's facial expression in real time."
In addition, the engine generating the faces in cut scenes shows damage taken during play, as well as subtleties like realistic wrinkles and tears to convey emotion.