THE RATATOUILLE CHALLENGE:
CREATING ADORABLE BUT BELIEVABLE RATS

With so many original characters and situations, RATATOUILLE constantly inspired the filmmakers to push the technology to new limits. Notes the film’s supervising technical director Michael Fong: “There were so many technical challenges to tackle on this film, starting with lots and lots of furry characters, as well as very complex human characters, intense water scenes with rapids and the recreation of the beloved city of Paris. Along the way, we significantly changed the way we shaded models, the way we light the scenes and the way we do cloth. We took technology from our previous films and found ways to make it even better. And all of this contributes to a really different, original look that audiences will experience along with all the fun of the story of RATATOUILLE.”

The challenges began with animating a whole new species never tackled before. The animators at Pixar have created all manner of menageries from toys to bugs to fish and even monsters, but even for them, rats were an unexplored – even forbidden -- species. Often type-cast in bad guy roles in cartoons, rats haven’t always received a fair shake in the animation world. But for RATATOUILLE, the filmmakers decided to look at these new furry friends from a fresh perspective, re-assessing some of their most amazing talents and qualities, and analyzing every aspect of how they interact with the world, from the swish of their tails to the twitch of their whiskers to the amazing shapes they can assume, to find the joyfulness and expression in their beings.

Since the best way to get to know rats is to spend time with them, the offices of Pixar were soon adorned with curious pets in cages. Although it took some getting used to, many of the filmmakers quickly found themselves feeling quite affectionate towards the socially minded critters, which inspired their designs even further. Explains the film’s character supervisor, Brian Green: “We spent a lot of time at first just observing and getting to know the rats and then incorporating all their behavior into models so that, ultimately, the animators were able to give them such compelling performances. Living with rats, you really get to see all of their little mannerisms. They’re really quite social animals. They’ll play with you and even cuddle on your arm.”

Continues supervising animator Dylan Brown: “We like to respect the real nature of the animals who become characters in our films and then build caricature and personality on top of that. With RATATOUILLE, the challenge was to find ways to get these little guys and their world to be very appealing just as we found ways to make fish, which aren’t really thought of as being that cute, appealing in ‘Finding Nemo.’”

Watching their new pets lead their daily lives also gave Green and his team plenty of fun ideas and opened up new areas of exploration. “One of the things that became very important to the film is that we began to realize how squishy rats are. A rat can do all kind of amazing things with its body – they go through tiny holes you would think impossible or shrink into a little tiny ball because their rib cages are so small and flexible – and that was something that we knew would be a lot of fun inside the story. But first, we had to create special technology to simulate that and try to capture it in a way that was realistic,” Green explains.

Supervising technical director Michael Fong continues: “There are a lot of challenges in making a rat squishy. It involved a really laborious and long process where the animators and the articulators – the people who actually build the skeletons inside the characters – would test models over months on end to figure out how to create all the extreme poses with all the skin and fur and bones all moving in a way that looked both right and expressive.”

Once the filmmakers had a better sense of how rats move in real-world situations, their investigations quickly moved into the fantastical -- how, for example, would a rat such as Remy hold a spoon or a pan?

“We needed to build into the rat characters the ability to interact at the human level and to actually cook with human chefs. There were a lot of challenges there, especially in managing scale,” says Green. “You see the difference in scale even in a simple thing, like heartbeat. When Remy is running you can see his heart fluttering really quickly, while Skinner is breathing at an entirely different rate. Trying to capture these differences really sells the story as a believable meeting of two worlds.”

Shading was also key. “Each of the rats has their own palettes to make them even more appealing and interesting,” explains shading art director Belinda Van Valkenburg. “We used pointillism to mix different colors for each character. So if you look very closely at Remy’s hair, he’s got purple, yellow and green hair. But if he’s far away, he’s just a nice shade of blue.” Van Valkenburg also looked to peaches for inspiration. “I wanted them to have cute little peach fuzz on their noses and ears, as well as their tails.”

The biggest challenges of all came in creating Remy, who tries to straddle the rat and human worlds with often hilarious results. Bird made the decision that while all the other rats would walk around on all four legs, Remy would teach himself to stand up on two legs – to avoid the faux pas of dirty paws scampering all over the food! “Ultimately what happens in the movie is that Remy evolves,” Green explains. “He starts off very rat-like, but as he goes deeper in the human environment, he picks up more and more human characteristics. It was a lot of work but it really introduced a lot of magic into the story. For Brad, the real heart of the story was always that this was an outsider trying to fit into a human world.”

Rats also bring with them another tough job for CG animators to tackle: fur, which has its own highly dynamic, and not easily imitated, ways of moving with an animal. While Pixar had pioneered new methods of handling fur and hair in “Monsters, Inc.” and “The Incredibles,” for RATATOUILLE, the fur was literally flying. “This time, we had thousands of characters with hair, and all that hair needs to interact with everything else that’s happening,” Green notes. “So we had to really upgrade our ‘hair pipeline’ to allow for this. This meant a lot of angst but also a lot of new, clever tricks.”

While real rats might have as many as half a millions hairs, that was, well, a bit too hairy even for today’s computers. Instead, the filmmakers focused on some 30,000 “key” hairs per rat, which was still a massive undertaking. “We choose key hairs to simulate and then rendered the rest because otherwise we would have more data than you could possibly store,” comments simulation supervisor Christine Waggoner. “Even so, we still had huge files of hair!”

The rats of RATATOUILLE might have an engaging realism, even humanism, to them, but they are also very much a part of a fairy tale – which becomes especially clear in the scenes in which Remy controls Linguini like his own chef marionette. For the filmmakers, the entire success of the film hung on getting the audience to believe in this fantastical and funny notion. “The animators worked it out so just the slightest tug of Linguini’s hair creates a movement of his hand,” says Brad Lewis. “It’s just so funny. This film has so much old school Buster Keaton physical humor, it has you laughing your pants off without a single word being uttered.”

NEXT
RATATOUILLE’S PARIS:
A BREATHTAKING NEW WAY TO LOOK AT THE CITY OF LIGHT
Paris may be the most photographed, painted, written about, dreamed about and adored city in the world – but RATATOUILLE manages to take an entirely new look at it. The story of RATATOUILLE unfolds in two very different but equally enchanted sides of the city: an ethereally charming and urbane world of restaurants and cafes above ground; and the intricate, mysterious, industrious realm beneath the streets where Django’s furry family makes their home.