ABSTRACT
When it comes to intelligence in linear animation, the behavioral modeling of the character happens in the mind of the human artist. Animators, writers, and directors define and execute the behavior that the characters should undertake. In interactive animation, the modeling of character intelligence that will be seen by an audience happens instead inside the animation system itself. The creative team designs the behavior, and this interactive system acts as an intermediary between the artists and the audience. During an interactive animation production process, like those we have discussed for procedural animation, animators and programmers produce the raw material for believable behaviors and the rules for connecting them, while linear animators produce the behaviors themselves. This distinction can be frustrating to a linear animator and often requires that they only produce “cycles” or discrete motions. It is also more difficult to document the work that has been done by a single artist. It can be an interesting new undertaking to think through a character in sufficient depth to determine all possible actions and reactions that the character could take, but this is a very different prospect than working through a complete performance by a character over the course of a moment in a film. Another frustration for animators transitioning from linear production to interactive work is that, when animating for interactive products, it is not possible to see the final form that the animation will take in every possible situation. The animator can play-test the game and get a broad sense for the way an animation will look when it is finally rendered and make revisions based on that process. For linear animation, animators typically animate “to the camera,” meaning that the camera is placed first then the character is posed for the shot. The position, orientation, size, and other features of on-screen elements, including character components, may be adjusted (also know as “cheated”) to the camera to make a scene look better. Often, when viewed from other angles, the character looks totally broken and offcamera elements may not even be animated. Digital characters for 3D interactive work must read in-the-round at all times, and due to the broad range of potential interactions among interactive characters and their environment, there can be no
Rob O’Neill 15-Ch14-P372561 2008/9/15 14:13 Page 274 #4
final round of hand-tweaking by the animator to make sure that every element of the scene works together.
