Martin Costello on the Digital Clay of "Flushed Away"
Every year, ACM Siggraph holds a convention on Computer Graphics, around the United States. This year the convention came to the Boston Convention and Exhibit Center.
Everywhere there were collaborative drawing tables, artistic toys and tech that would put James Bond to shame. Fountains you could “sculpt,” a tabletop cartoon theater, and even a full-body version of Dance Dance Revolution and a game that challenged players to “vacuum” up shadow monsters.
Big film companies like Dreamworks, Pixar, Sony Pictures Imageworks, Disney Animation, and Lucasfilm displayed alongside technology companies like Wacom, Z-Brush, Autodesk, and various schools and colleges. Along with booths of all types and sizes, there were displays and demos of new technology for film, television and gaming as well as household use.
Two of the highlights of my visit to Siggraph were a presentation given by Martin Costello from DreamWorks Animation on the new film Flushed Away, and the chance to ask him some questions about the project later on that day. Costello’s presentation gave us a glimpse of the character rigging utilized in the new all-CG film, now in theaters.
Costello described the choices in rigging that were made to tie the CG film’s look and motion to its all-clay siblings from the Aardman Animation studio, DreamWorks’s partner on the project. DreamWorks focused on a rig that was similar to the physical skeleton armatures used in films such as Wallace and Gromit. The skeletons for the CG characters such as Roddy and Rita the rodents were simplified and more rigid in nature. This was illustrated with an overlay of the computer character over the traditional Aardman armature. Costello noted that while the rig for Roddy was more similar to the traditional skeleton, and resulted in similar movement, the rig for the character Rita required a few more points of movement in the spine to get a little more feminine movement.
He spoke about how some of the animators from Aardman made the transition to the computer for Flushed Away. He also noted that the skilled animators picked up animating in CG rather quickly.
The presentation also touched on facial animation and rigging, providing us with a view of how they strived to make the CG behave like the clay did. Important things like the “monobrow” seen on characters like Gromit were carried over and taken into consideration in rigging for the computer characters. They also rigged the CG characters to help the animators get the snappy look that Aardman has in its animation. That, along with the decision not to animate on “twos,” helped create similar movement. Other details included blendshapes akin to the mouth shapes for each sound or vowel used by Aardman.
TZ: I know you mentioned [in the presentation earlier in the day] that there were more joints in Rita because she needed a little more movement. Did the Aardman animators, because they were used to using a much more rigid system, have any problem adjusting to it to get that extra movement in there, or was that more freedom for them?
Costello: No, they’re very adaptable. They just get it. They adapted quite quickly.
TZ: Was the animation interface for the characters designed for ease of use, for having the maximum ability of controlling and moving, or a little bit of both?
Costello: A lot of work went into it, and it’s laid out in a very literal way. A lot of colored buttons. It looks a bit like Fisher-Price, color coded. The mouth, laid out in mouth rings, has blue rings, red rings—
TZ: For movable joints?
Costello: Yeah, and there’s actually a separate control for the mouth shapes. You can access the mouth shapes, and it’s a general GUI, and it’s completely separate.
TZ: In the presentation, you showed maybe a line-up of six heads to be switched out. Was it the whole head that was switched?
Costello: It’s like a blend shape we’re using, mostly the mouth area. We’re trying to mimic what Aardman does.
TZ: Because you have the individual points in the face, and there’s the monobrow too, and I didn’t know if it was the whole head getting switched out as a blend shape.
Costello: It’s like a blend shape. They used them pretty strictly. They didn’t mix up shapes.
TZ: Like “pulling them out of the box” – as though the heads were made out of clay.
Costello: Like a wide-open “E,” and then other vowels, maybe a little bit of an “Oo” just to push it forward slightly.
TZ: I saw you showed the facial rigging today, and, especially for “pulling” individual points in the face, are those keyable individually or can you key them as a group as well?
Costello: Yes, you can key the whole. I mean, we’ve got this whole thing I didn’t show, the Graphical User Interface thing where they can pick all the controls. They can pick out rows, and diagonals, the whole lot. The GUI we spent a long time on as well. But that’s a whole talk itself, but it kind of mimics how they built the character.
TZ: I know you said expression inbetweens are not totally from one to the other, there’s a little bit of a twinge in the shot from one mouth shape to another.
Costello: Yeah, and I know even when it came out of modeling, they still have to get out of shape. We add the shapes and what they can do, then pose them, and then we can rebuild the rig and actually store that in there like a pseudo-shape. Basically it’s a shape made up with keys.
TZ: You also added “crows feet” for particular character expressions. And something that has always amused me was the use of footage of the voice actors in creating some of the facial expressions used in animation. I’ve seen with some movies, they videotape the voice actors to get some of the facial expressions in there. With Aardman – because it’s the style of Aardman, would the animators fall on using any of those voice actor tapes?
Costello: They always do that on the voice recordings, I’m not sure, but we don’t need that a lot. The Toad is Ian McKellen, who’s “hamming out.” He’s very Shakespearean about acting there, but I don’t think we need [the videos].
TZ: What did you enjoy working on the most with this project?
Costello: Working with the Aardman people. Spending time with them and finding out how they do things—getting paid to actually look at Aardman Animation, it was pretty cool. And that monobrow, actually, that was my whole thing on the show, and that went way overbudget, but it was worth it.
DreamWorks and Aardman’s Flushed Away is in theaters now.