Fizt (physics tool)

Fizt (pronounced FIZZ-tee, and short for physics tool ) is an animation program that can speed up the production of special effects -- in some cases by a factor of more than 150 to 1 -- and can also make the effects appear more life-like than has been possible with less sophisticated programs. Developed by David Baraff and Andy Witkin of Pixar Animation Studios, Fizt is said to incorporate the natural laws of physics to control the behavior of virtual objects in computer animation.

Until the development of Fizt, realistic animation of certain effects, such as hair blowing in the wind or the wrinkles in a shirt moving with its wearer, was practically impossible to achieve. However, in the animated movie, Monsters, Inc. , such effects were accomplished, including a virtual creature with more than two million movable hairs. Instead of animating each hair individually, the whole array of hairs was programmed to move according to real-world physical laws.

In addition to simulating the movements of fur, clothing, and other materials, Fizt makes it possible to portray a wide variety of emotions in animated characters by enhancing facial expressions and the realism of body language. Because Pixar believes that effective animation starts with a good script, their technical animation people now take a screenwriting workshop so that they can learn when to best insert, for example, an imbecilic grin or a dejected sag of the shoulders.