In helping realize Tim Burtons vision for the Nut Room factory sequence in CHARLIE AND THE CHOCOLATE FACTORY, Framestore CFC delivered photoreal digital, working closely with vfx supervisor Nick Davis. Combining its artistry with footage of both real and animatronic squirrels, Framestore CFC delivered 130 shots for the film, including some 64 featuring CG squirrels.
When the touring party arrives at the Nut Room, they find an enormous circular chamber. It is staffed entirely by trained squirrels sitting on stools around the room. Their job is to test nuts by tapping them. Good nuts get put into Wonka chocolate bars, bad nuts are discarded down the garbage chute a large hole in the center of the room. Veruca Salt decides that she simply must have one of these delightful creatures and, against Wonkas advice, heads into the room to grab one. However, when she makes to grab a squirrel she is leapt upon and falls to the ground. A squirrel rushes up her and taps her head. Having ascertained that she is indeed a bad nut, the squirrels sweep her along the floor on a living carpet of squirrels, and dump her unceremoniously down the garbage chute.
According to Framestore CFCs vfx supervisor, Jon Thum, We started with some very rough boards of the sequence, and we presented Tim and Nick with a previs that answered the two big questions about the scene: how and where to get Veruca down onto the floor, and how to then pick her up and get her down the hole. When we showed him our ideas, Tims response was: I love it. More energy! by which he meant, More squirrels! essentially. We shot it pretty much as prevised. Fortunately for us, we were given a lot of leeway and trust by the production team, and we were able to choreograph most of the scenes elements ourselves.
Added animation supervisor Michael Eames, Another advantage of being involved at the previs stage was that we were able to design and develop animation, both generic and specific, before the shots were actually filmed, which gave us more time to work on shots that needed more specific crafting.
Thum, along with Eames and CG supervisor Ben Morris, selected the camera angles and shots with which they would tell this mini-story. There was one big change that Tim made, relatively late in the process, said Thum, And that was the removal of any suggestion of teeth being used by the squirrels it would just have looked too harrowing for younger viewers. So we limited the CG squirrels interactivity with Veruca to their paws. In fact, it worked out beautifully, as the shots we created after that decision were some of the best we did.
While the animatronic squirrels were finally used in only one shot, as background, the trained squirrels were actually used in several of the early shots in the Nut Room. Wed thought we might use footage we shot of them running over her arms and so on, Thum explained, But once they hit the floor, its so highly choreographed, with every shot crucial to the cut, that we were better off using our CG squirrels.
With up to 100 squirrels on screen in some shots, and each squirrel clad in a 5 million-hair fur coat, the technical challenges facing CG Morris and the team were considerable. We worked in Maya, Houdini and RenderMan, said Morris. Along with various proprietary tools. These included fcFur, which we developed to handle the fur, and Choreographer, developed to allow animators to handle scenes featuring scores of characters. As far as rigging the creatures was concerned, we had one rig developed by David Short and Michael Eames in Maya, which was capable of being used in all shots and postures. This was no small feat as squirrels seem to have no notion of gravity or natural orientation they are just as happy standing on four legs, two hands, upside-down, on their backs, you name it...
Added lead TD Andrew Whitehurst: Everyone has a mental image of what a squirrel looks like, but when you look closely at them and you dont get closer than a cinema screen theyre all different. So coming up with a generic squirrel was very hard. We went through countless iterations of geometry for the actual creature, as well as the fur on top of it. We ended up with seven different fur descriptions on the creature: back fur, under fur, belly fur, facial fur and so on. The idea was to create one master squirrel, and then branch off from that with the variations.
In addition, when we started to see plates coming back, the Nut Room was lit with a very flat light. Fur is much easier to light when youve got a strongly directional light source, so there was a big challenge in rendering fur efficiently using hard lighting sources. Basically this involved a lot of tweaking of individual lights, and then a lot of playing with things during the composites using arb-outs (arbitrary outputs) so that we could reconstruct different elements of the lighting.
The key moment animated by Craig Bardsley is one of near stillness, as a squirrel approaches the prone Verucas head and taps it, prior to her being swept off to the garbage chute. In a sense, this was the ultimate challenge, added Eames, We needed to have convinced the audience by then that they were watching real squirrels, and then carry them on a wave of suspended disbelief through an action that would never happen in real life. We used all the observation and research we could to imbue our creatures with a wealth of realistic tics and movements, and then applied this squirrel paintbrush to the creature while it did something quite unbelievable.
Framestore CFC credits:* VFX Supervisor: Jon Thum* CG Supervisor: Ben Morris* Animation Supervisor: Michael Eames* CG Lighting Supervisor: Andrew Whitehurst* Compositing Supervisor: Gavin Toomey* Compositors: Craig Rowe, Ellie Meure, Corrina Wilson, Adrian Metzelaar, Matt Twyford, Kate Cuffin* 3D Animators: Craig Bardsley, Brendan Body, Maurizio Parimbelli, Rosie Ashforth, Craig Penn, Federico Cascinelli, Mathieu Vig* Technical Directors: Andrew Chapman, Neil Wetherley, Matt Hughes, Chris Lawrence, Mike ONeill* Character Riggers: David Short, Matthias Zeller* Modeler: Matt Hughes* Camera Technical Directors: Ben Loch, Paolo Mitton, Duncan Robson, Marc Smith* Paint Artists: Steve Parsons, Dan Macrae, Giacomo Bargellesi* VFX Editorial: Kerry Downing* VFX Avid Operator: Tom Partridge* Data Operators: Rebecca Manning, Matthew Jacques* Systems Support: Christophe Meslin, Rodrigo Bernardo* Render Support: Alex Hessler, Stefan Putz* VFX Producer: Lucy Killick* VFX Coordinator: Lorna Paterson
London-based Framestore CFC (www.framestore-cfc.com) is one of the leading visual effects company working on effects for feature films and commercials.
Bill Desowitz, former editor of VFXWorld, is currently the Crafts Editor of IndieWire.
