12/03/2019

Jos Stam is the subject of a computer graphics seminar at IMPA.

Trupe do Toy Story ficou mais “real” com técnicas que usam a matemática. Crédito: Disney/Pixar

Take a good look at the most famous toy troupe in world cinema. Aren't the movements and expressions of Woody the cowboy, Buzz Lightyear the space ranger, and even Mr. and Mrs. Potato Head impressive? Well, know that there's a lot of math involved in "Toy Story," the first feature film made entirely by computer. Since its first edition in 1995, the film has won legions of fans for its script and effects that make the inanimate "real."

If you want to know more about research in geometric modeling, animation and simulation by a master in the field, schedule yourself: Luiz Velho, coordinator of the Computer Graphics Laboratory (Visgraf) at IMPA, presents, at 1:30 pm this Wednesday (13), in auditorium 3, the seminar “Jos Stam: from art to Science”, about the Dutch mathematician, winner of three Oscars in the scientific and technical category for research in 3D modeling.

The latest award is a joint achievement with Pixar co-founder Edwin Catmull – responsible for “Toy Story”, “The Incredibles”, “Monsters, Inc.”, and “Cars” – and Tony DeRose, a researcher at the studio. The trio was recognized for their pioneering work in the science of subdivision surfaces, a technique that underpins the visual magic of animated films and box office hits like “Avatar” and “The Lord of the Rings”.

Stam na cerimônia do Oscar: três estatuetas no currículo

The technique allows for the repeated cutting of surfaces with harder edges to produce a smooth, rounded surface, thus generating images closer to reality. Stam, a researcher at the University of Toronto (Canada), developed a shortcut for the technique, which led to the development of geometric modeling, used in film, industrial design, architecture, and manufacturing.

In cinema, mathematics is used, for example, in all stages of computer-animated films: building environments and characters; specifying movements and camera work; and synthesizing images, that is, the actual editing. In computer graphics, they represent three basic areas: modeling, rendering, and animation.

To create a virtual scene on a computer, the geometric shape and spatial position of each object in the scene are mathematically represented using spatial analytical geometry. Since objects can have very complex shapes that are difficult to represent, techniques have been developed to generate images closer to reality, transferring objects from the continuous world of mathematics to the discrete world of computers. One such technique is precisely that of subdivision surfaces.

Want to know more? Come to IMPA tomorrow at 1:30 PM for the Visgraf seminar.