Autonomous Characters and Animation

Bill Tomlinson's paper concerns itself with one of the fundamental problems facing the portrayal of believable characters within a computer game: the automation of their interactive animation. If a character is to cause us to emphasize, then it should behave in humanistic ways. Essentially, this is the second of the two main problems encountered by the creation of agents such as the movie S1m0ne's synonymous AI movie star (the first problem is behavioural automation). Indeed, this paper makes the connections back to Hollywood animation, where linear procedures (whether traditional or digital) allow animators to breath life into their characters with a mimicry of human activity.

In a computer game, where dynamic behaviour is desirable -- that is, the automatic performance of activities by a character -- the next question becomes, how will that behaviour be portrayed? Tomlinson locates these differences along 5 axes: intelligence, emotional expressiveness, navigation collision avoidance, transitions, and multi-character interaction. In order, these require animators to specify suites of behaviour to deal with visible decision making, feelings, the intersection of two characters while moving, the smooth look of animations in between specific states, and those complicated sets of actions such as a fist-fight or a romantic scene.

In each of these cases, Tomlinson mentions recent attempts to solve these problems, but his greatest success seems to be a thorough revealing of the problematic areas of dynamic character animation.