Some of the most memorable characters in Tim Burton’s ‘Alice in Wonderland’ are theanimated
CG creatures and personalities that emerged from Sony Pictures Imageworks
studios, from the hookah puffing Caterpillar to the fearsome Jabberwocky.
|As Animation Director at Imageworks, David Schaub supervised the character builds and performances of each one of them with a seasoned team of animators.
“We created all of the non-human characters in the film,” David said. “We ended up with over 30 characters and produced more than 1100 shots over a course of nine months with a team of 60 animators divided into eight different teams. We also had a small animation team at CafeFX that handled the book-end shots and some additional animation of Bayard and the Red Knights in Underland. We got started with movement studies in April 2008, after Senior VFX Supervisor Ken Ralston had already spent about six months working with Tim Burton on character designs with a team of development artists.
Tim gave David’s team plenty of freedom to experiment with characters, resulting in one of the most rewarding and collaborative experiences that he’s had. Tim’s confidence with the crew meant that he could allow them to explore while keeping his eye on the bigger picture, and steering the creative process by providing guidance along the way. David noted that Tim handled all teams and the whole production in this way, and was a great collaborator on all levels, encouraging each team to find answers on their own.
Wacky to Traditional
By this time, script writing had been virtually finalized by Linda Woolverton, and Tim’s production team had produced storyboard panels and previz for some of the trickier sequences. David’s team were free to focus on characters and getting performances from them to realise this story.
So, they simply aimed to rig for about 80 per cent of possible cases, and didn’t worry too much about the extreme, ‘hero’ shots that were always going to present a challenge. “We don’t refine the character to the highest level of detail until we’re faced with a specific demand,” said David. “Then we can build controls for that particular case, and the character rig controls and features evolve as we work through the show.”
The animators had their rigging lead Aaron Pfau working with them through to end of production. Instead of simply rigging a character, handing it to the animators and moving on to some other project, he helped them add a ‘shot finaling’ step. Once the basic performance was approved by the director, Aaron’s team would add special touches like folds in the skin, additional tendons and muscles designed for the shot, as well as a skin dynamics and ear simulation for a character like the Bloodhound.
This flexible approach represented a shift in thinking for a large production like this where over-engineering tends to be the typical approach. “It also opens the possibility of keeping a simple set of generic rigs and embellishing them as needed,” said David.
They decided they would avoid humanising any gestures to align with actor Stephen Fry’s dialogue. Instead of moving his hands, he would roll around and flick his tail, like a real cat. However, how was he going to fade in and out of view?
Poses and animation nuances were inspired by Ray Harryhausen’s classic fantasy creatures, which Tim and Ken Ralston both admire. The big ‘reveal’ moment of the Jabberwocky was a direct recreation of ‘Night on Bald Mountain’ from ‘Fantasia’, 1941.
Crispin Glover played Stayne, the Knave of Hearts, but the only photographic element of Glover that the character designers actually used from his performance was his head. “The rest of his body is completely CG. From the point where the skin met his collar was green all the way down, partly as a means of accelerating the shooting schedule and partly because they didn’t know what the costume would look like for quite a while. He was simply another strange character in this strange world,” David said, “Eight feet tall and lanky, that was really all we knew about him going into this, and details about his costume were figured out long after the shoot was complete.”
The photographic element of Crispin Glover’s head was extracted from the plate and stabilized about a point at the base of his neck. That image was applied to a card, and the card attached to the animation rig and orient-constrained to the camera. That means the head was no longer locked to the position that it was in the plate and gave the animators freedom to move the character around in the scene as needed. Once the performance was approved, fine tuning of the tracking was done in Katana - Imageworks in-house compositing software - and in some extreme cases was stabilized and tracked in Nuke or Flame.
Because the one actor handled the Tweedles single-handedly, they can be regarded as one, hybrid character. Otherwise, like Stayne they were totally animated CG characters. The pair’s creep factor particularly appealed to Tim, inspired by the nightmare twins from ‘The Shining’.
The animation of various inanimate objects in the sets, many of which turn out to be animals with the job of holding furniture in place is a distinctive feature of this film, and kept David’s team busy. Large contingents of monkeys holding candlesticks at the Red Queen’s court, for example, serve her silently in terror while frog footmen stand at attention in the background, frozen in fear of losing their heads. The frogs’ ability to express this fear with great subtlety was important.
In one sequence, one of the frogs undergoes an interrogation from the Red Queen. He is virtually frozen with fright, but the tiny flickering movements just visible in his throat as he gulps and of his bulbous shining eyeballs, portray a guilty conscience better than grand, dramatic gestures would have done. Very precise timing was critical.
Geometry of a Smile
David described some of the special problems that certain characters posed. The Cheshire Cat’s smile spanned a challenging range of movement, from when the cat makes a narrow contracted ‘ooh’ sound to his wide ear-to-ear grin. “Technically, this represents a huge stretch of geometry,” explained David. “Fur thins out when it’s stretched and bunches up when compressed. “Also, when he smiles, we had to add controls to deform the internal palette so that the teeth would track along with it. We realised that smiling separates the mouth from the teeth, revealing the gumline and skull, and needs controls to curve the interior of the mouth to show teeth top and bottom.”
“The March Hare’s character was developed fairly late in production. The brief there was for a crazed, jittery creature, constantly twitching and moving. The Caterpillar, sitting on his mushroom, needed organically flowing movement and also had to interact with CG smoke that the FX department added to the shots, which meant we had to anticipate his eyeline for smoke that would be added later. His fluid facial movements were critical, but fortunately we could start with our generic facial rig that gave us about 80 per cent of what we needed, and then added controls to extend the range. The Bloodhound had loose baggy skin that required, as mentioned, a further simulation layer on top of the animation, and extra facial controls for his expressive eyes and brow area.
“This project really was demanding in terms of time frame and the sheer number of characters and the diversity of techniques applied to bring the imagery to the screen,” David said. The large, diverse team at SPI, and their ability to collect large amounts of data about characters and performances, is a valuable asset. We place witness cameras on set to collect our own version of the footage captured for the movie, but we also place other cameras around the stage to capture a scene from different angles. When it’s time to animate, the plates are scanned, the team looks at the shot and gets started. If they want to see it from another angle they can stop and look at that. All the data is catalogued to refer to later.
“It’s not often necessary but in Stayne’s case, because Glover’s head had to be tracked back in, they really needed to see all angles to accommodate the effect the 3D would have on the image. They had to register him in z-space as well as x and y.”
The film was not shot with a stereographic rig. The 3D was applied to the photographic elements later as an effect while our CG worlds could simply be rendered with two cameras. Nevertheless, the animation team had to be aware of special demands that stereo 3D would place on their performances. For example, the usual ‘cheats’ that animators can rely on in 2D, such as when live action and animated characters touch no longer works. When the Tweedles hold Alice’s hands, one on each side, their hands could be visually joined in 2D without too much trouble using light and shadow effects to perfect the connection. But in this production, that contact had to be ‘real’.
“Alice herself had to be dimensionalised, and her photography needed to be rotomated – that is, a CG version was made of her, animated to match her precise movements. The live photography was projected back onto the geometry of the CG ‘double’, and the Tweedles could then grab this double’s hand.
“Eyelines are complicated as well by the third dimension. When two characters are looking at each other, eyelines won’t work if one of them appears to be standing deeper into the set than the other. In post, the stereo could be applied to each character separately to correct the problem but obviously, this made the process more complicated. Also, character performances that looked right in 2D may appear tipped, leaning backward or forward, after 3D has been applied. We had to remember this while we worked, and really focus on balancing a character correctly on all three dimensions.”
|Words: Adriene Hurst with David Shcaub
Images: courtesy of Walt Disney Studios