Yoda and Beyond: Creating the Digital Cast of Star Wars Episode II
“Something we’ve never seen before…”
Sunday, 21 July 6-8pm
Ballroom A
Panelists: Geoff Campbell, Rob Coleman, Zoran Kacic-Alesic, Sebastian Marino, James Tooley

By Tai-San Choo
7.22.02

Given the line of a thousand or so attendees packed out the door of the Henry B. Gonzalez Convention Center half an hour before this first Special Session panel of the conference, the impact of Industrial Light + Magic within the graphics community is clearly enormous. While being squashed along by the horde of people, I had a chance to stop and reflect on how ILM is one of the main reasons I got into computer graphics and film production in the first place. What better way to start off SIGGRAPH 2002. Expectations were predictably quite high for one of the year’s most popular panels. They didn’t let us down.

This year’s panel discussed the increased usage of a digital cast in Episode II, most notable going from the classic puppet rigged Yoda to a fully digital wise little green jedi master. Animation Director Rob Coleman explained the fateful day George Lucas revealed the script for Episode II, only two days before the shoot date, when he flipped to the page of the Yoda fight sequence. Lucas only described the fighting style as something like the Tasmanian Devil or an evil frog, before asking that it be “something we’ve never seen before.”

Lead modeler Geoff Campbell started off the session emphasizing the need for Yoda’s new body to be a fully reconstructed digital version of the original Jim Henson puppet, with the same subtle tendencies and emotions reflected in Frank Oz’s performance from Empire Strikes Back. Demo footage showed side-by-side comparisons of digitally recreated Yoda’s from the original Empire scenes. Even slight movements such as eyelid flickers, forehead contractions, and ear movements had to be recreated and animated. The ILM modelers used everything from old Yoda footage, to watching video of themselves to decide facial points, to having Oz come in and demonstrate his puppet hand movements without a puppet to get a sort of internal skeletal structure of Yoda.
Before Sebastian Marino’s segment, many attendees left for the annual sake party and missed out on a lot of the fun to come. Marino, a lead developer at ILM, talked about their Creature Dynamics system and how it was used in modeling flesh and cloth, and creating seamless transitions between live action and CG elements within the film.

Zoran Kecic-Alesic, another lead developer, displayed his penchant for blowing things up with a reel containing various scenes of ships exploding and battle droids being sliced apart from various angles. He used this to explain digital volume dynamics and the use of constraint joints. At sessions like this sometimes you get the feeling that this is one of the few opportunities for developers in feature films get to carp on about all the time and effort that was put into some of the most miniscule elements of the movie. One such example was fixing a bug in the software that kept making the bracelets fly off one of the characters.

With 80 total digital creatures and 31 with simulations in Episode II, there was bound to be room for some error. Technical animation supervisor, James Tooley received huge laughs with his blooper reel of control systems gone haywire. Clips included those of Jar Jar Bink’s costume inflated and Dexter the diner owner’s pants falling down.

As a late addition to the panel, Coleman ended the evening with a bang by explaining the process of creating Yoda’s unique fighting style for his battle with Count Dooku. There had to be a way to show his immense skill with the lightsaber to match his abilities using the force from Empire Strikes Back. Some films Coleman noted as references for the fight were Kurosawa’s Seven Samurai, Yojimbo, and Sanjuro, Bruce Lee’s Enter the Dragon, Jackie Chan’s Drunken Master, and Jet Li’s Shaolin Temple. A clip from the blazing sword battle scene in Jet Li’s the Swordsman 2, turned out to be the basis for Yoda’s style. The crowd brought out with laughter when he showed the side by side footage of the finished segment with a screen test for positioning showing a sized down clip of Michelle Yeoh in Crouching Tiger, Hidden Dragon in place of Yoda on the frame.

For the throng of SIGGRAPH attendees packed tightly into Ballroom A, the treat of seeing the behind the scenes graphics team from ILM was well worth the wait, and proved that someday we may not be able to determine a fully digital cast from the real thing.

SIGGRAPH 2002