'Free-for-All is a computer-generated animation which tells the story of a party of autumn leaves which invade a lonely playground. Unaware of the watchful presence of a zealous trashbin, the leaves cavort about the playground equipment, riding on the wind currents and dancing in the sky. Suddenly, one unlucky leaf falls within the reach of the trash bin's sharp rakes. The trashbin skewers his quarry and swallows it on the spot. Terrified, the other leaves cease their frolic, but it is too late. The trashbin rushes toward its victims, pursuing them around the playground and trapping them behind the shed.

The leaves rise in the air, but the trashbin opens his lid and sucks them all back in a whirlwind, swelling to grand proportions as he does so. He slams his lid shut, but holding his breath with all those leaves inside is too much. With a terrific sneeze his lid pops open and all the leaves are carried heavenward by the blast.
The goal of the research effort that produced 'Free-for-All is to employ physical simulation to generate realistic motion in computer animated scenes. The motions of the leaves and swings were generated by using an aerodynamic model which automatically generates the motions of objects in response to the forces of a simulated wind. (Alan Norton)

Technical Background

HW / SW: Silicon Graphics, In-House SW

Alan Norton (USA), received his B.A. degree form the University of Utah in 1968, and the Ph.D. from Princeton University in 1976, both in mathematics. He was instructor at the University of Utah, 1976-79, and Assistant Professor at Hamilton College 1979-80, before joining IBM Research. He worked with B. Mandelbrot, developing algorithms for generating fractals and making images of them.