Weta Digital on the making of The Adventures of Tintin
Weta Digital embarked on a new quest with The Adventures of Tintin, complete with crashing waves, pirate battles and an extremely stylish wardrobe. Renee Dunlop takes us behind the scenes
As the Blu-ray of The Adventures of Tintin goes on sale, we thought we’d share this article from issue 152 of 3D World magazine.
If you haven’t watched the film already, we suggest you do – The Adventures of Tintin looks like a mix of live-action and CG, which adds up to something unique on screen. It’s possible that The Adventures of Tintin missed out at the Oscars this year because of this very thing, which is a real shame as we think the film has some of the best CG we’ve ever seen.
Weta’s Adventures of Tintin
Weta Digital is delving into a new world – that of the journalist. Enter Tintin, a popular post-World War One comic strip hero who travels about with his dog, Snowy, cracking cases with a little help from his friends. Created in 1929 by the artist and writer best known as Hergé, the stellar artists of Weta, led by director Steven Spielberg and producer Peter Jackson, have brought the story to 3D animated life on the big screen.
It took some of Weta’s best to tackle the wide array of arduous effects required to complete the film. Keith Miller, one of five VFX supervisors, was among those appointed to the task. He was in charge of roughly 340 shots.
An epic sea battle required Weta Digital’s team to simulate stormy ocean waves
For Miller, the big challenge was the pirate battle. “It’s such a dynamic sequence,” he says. “There are nearly 60 pirates running about, two ships that are sailing in 60-metre seas complete with lightning storms, rain, hurricane winds, fire, explosions – you name it, it’s all there.” The most difficult challenge was the water, with 60-metre waves interacting with the ships that needed to compositionally match the representations provided by the pre-viz team.
Miller’s team approached the work from a few different angles. “First, we updated our FFT [fast Fourier transform] library, a system of generating waves using measurements collected in oceanic research,” says Miller. They also completely rewrote their library using a more up-to-date spectrum that provided the ability to incorporate the ideas of the depth of the ocean and the fetch, or the distance that wind stays at a constant velocity. “We added those new variables into the system and we were able to generate much more realistic wave scenarios for the high wind systems,” he adds.
Weta’s FX team did quite a bit of work approximating the surface velocity from the newly generated ocean surfaces and applied those to Smoothed Particle Hydrodynamics (SPH) particle simulations, much of which was used for the white water simulation, breaking waves that rode on top of the ocean surface. These were pushed through Weta’s in-house 3D effects solution, Synapse, a node-based system that’s a container for solvers. In some cases, Naiad data was also incorporated into Synapse for the initial bounded simulation elements.
The battle sequence combines water, fire, wind and lightning, and featured as many as 60 pirates in combat
In addition to reworking the FFT system, senior water TD Chris Horvath updated Weta’s shading model for raytraced water, using an improved model for participating media for underwater light extinction and scattering. He also made improvements to the procedural texture foam system.
Creating the hands
While Miller and his team battled with the pirate ships, Weta’s digital creature supervisor Simon Clutterbuck focused on some of the smallest of details through his modelling department. “We build the animation puppets, the deformation rigs, we do all the cloth and hair simulations, muscle dynamics, flesh dynamics – anything that has to do with the monster or character,” he says. “We interact with all the departments in the studio to produce stuff for them to use, like the puppets or the baked light, and we work closely with shots and animation.”
The creature department work includes providing all the puppets for the animators. “Our animation puppet isn’t the thing that gets cached and ends up in the shot,” says Clutterbuck. “The animation puppets are kind of an interactive, almost real-time version of the character. They don’t have to see amazing hand deformations to pose the hand correctly, so they’re just posing [and] animating this thing that’s much lower resolution.” Clutterbuck’s Creature Department provides the animators with approximations of clothes and low-res hands and bodies that allow for faster animation. “Then the animation data is cached off of that puppet and plugged into a high-resolution creature rig, which gets cached and given to lighting,” he says. “This way there’s no requirement for interactivity in our actual deformation models.”
A single complex rig was used as the basis for all characters’ hands
It’s hardly all low-res work, though. “There’s a big focus on faces and hands in the show, so a good deal of time was focused on building a detailed hand rig,” says Clutterbuck. “We had all these incredibly close shots of Tintin’s hands. It’s a treasure hunt, so there are all these clues that lead to the treasure, and there are lots of shots where he’s inspecting things. The shots are incredibly long, so you’ll have minutes focused on their face or hands. The stability of the cloth solve, the fidelity of the hands [and] the deformation all had to be very high. It was pretty unforgiving.”
Weta Digital’s workflow uses a generic model called Gen Man as a baseline for building humanoid characters. This starting point is used for reference, scanning and motion capturing, tailoring clothes, and even cross-referencing MRI data. Clutterbuck explains: “We produced a whole bunch of life casts in all different poses that were used to build support moulds, 36 in all, that went into the MRI machine, so the character could put his hand into a similar pose and hold it there. Then we could derive the meshes of his joints from the MRIs.” The result was a series of high-resolution joint meshes of his actual skeleton in the selected poses.
The story is a treasure hunt, so there are lots of shots where the characters have to pick things up and be able to manipulate them
“The metacarpals in the wrist do all these crazy rolling motions – it’s really complex,” Clutterbuck says. “We couldn’t build that complexity into the animation puppets because it would have been prohibitive to animate with, but we also needed the correct degrees of freedom in the wrist and joints to give us the right deformations of the hand.” It took nearly five months to get the hands working the way they wanted.
“The hand rig looks pretty amazing,” says Clutterbuck. “The hand model propagates out into the show, procedurally warped into new shapes, so we built one hand rig and it was fitted to all the characters’ hands. We have a process that was developed on Avatar to transfer the rig and deformation data onto other models.”
Weta Digital’s model supervisor Marco Revelant was responsible for all the assets created in the model department and was involved with grooming and developing the fur system from the user side for the dog, Snowy. However, it was the clothing that both Clutterbuck and Revelant found the most challenging. The multiple layers and the way the different fabrics fell and moved presented a daunting task.
Folding the clothes
Weta Digital set up a Tintin-specific costume department that helped define the design of the clothing, offering insight into how the fabric would drape and move over a character. “The problem is,” says Revelant, “when you do digital clothing and give it to a modeller, the modeller will try to put in features like wrinkles and folds, but won’t necessarily take into account the quantity of fabric.”
Care was taken with getting clothing folds to animate correctly
To manage this issue, the Creature Department worked closely with modelling, providing tools that helped drape the character as they were modelling so that they could see how the fabric was behaving, rather than waiting until the Creature Department ran their simulations. Weta used NCloth in Maya, but spent a huge amount of time up-front shooting parameters and getting the topology in the models and construction correct, especially in cross-sections such as sleeves.
There are eight principal characters, and several have multiple costumes. In all, there were 551 individual costumes to build for the film
Several characters had multiple layers of clothing, requiring layers of geometry to simulate friction. There were eight principal characters, and several – including Tintin, Captain Haddock and Sakharine – have multiple costumes. In all, there were 551 individual costumes to build for the film. “Take the Captain,” Clutterbuck says. “He had a big woollen jacket, a woollen jumper, trousers, and socks and shoes.” Again, proper reference was key. Weta filmed a man running on a treadmill wearing a tailored suit they provided, and gathered reference on how cloth breaks across the seams, collecting data on details such as the effects of double versus single stitching.
Weta first tried just solving the visible clothing, but found that it didn’t quite look correct. “We ended up going for full coupled solutions where everything was solved,” says Clutterbuck. “Tintin might enter with his trench coat on, then take it off and toss it onto the back of a chair, and continue the scene wearing the rest of his costume,” says Clutterbuck. “We had to handle this level of complexity where we had all these variations of costume elements and they had to solve coupled. We hadn’t really done anything that complicated before in terms of clothes.”
Coupling affects even supporting characters such as Silk, who dresses in a formal jacket, a waistcoat and a shirt. “We didn’t solve the shirt, then put the waistcoat on, then the jacket,” says Clutterbuck. “We solved everything at the same time, so the solutions were all fully coupled. All the costume elements are plugged into one solver. Since they’re all plugged in, they all interact.”
Weta defers everything to its render wall. The costumes were assembled as a master file that contained a costume description. During the baked simulation step that file would assemble the costume, plug it into all the solvers, bring it in, attach it to the character, then do the simulation. The result was a final sim and a series of files generated to show what Weta calls pre-files, which are pre-simulation. The individual costume assets are iterated in parallel as an ensemble of costume elements.
“There’s a big focus on faces and hands in the show, so a good deal of time was focused on building a detailed hand rig,” says Clutterbuck
The costumes took several minutes a frame to simulate, but there was no interactivity requirement because that’s all happening on the render wall and animation was working with real-time puppet versions. “So we have these two parts of every character, with the puppet which goes to animation and the creature deformation model that’s the thing the animation curves get plugged into that simulates on the wall,” says Clutterbuck.
Weta’s flexible pipeline paid off, according to Miller. “I know a lot of facilities tend to lock down their technology, branch it off and continue developing it outside of current shows, but that’s very different from how Weta works,” he says. “It’s got pros and cons for sure, but it’s one of those things that helps us to stay at the leading edge of technology. We’re constantly throwing in new technology and updating and developing new aspects, and trying to get it pushed into production all the way through the course of the show.”
Setting the scene
The entire Tintin project was done in-house at Weta Digital, including the artwork for the environment and character studies. The translation of the environments from 2D to 3D was left to Weta’s modelling department under modelling supervisor Marco Revelant’s guidance. An internal art department was assembled to research information about the time when the film takes place.
“Every element that was drawn in the book, we tried to find the respective real element from that period that could have been the inspiration for the Hergé drawing," explains Revelant. "Everything was checked against real period data.”
“One important thing is [creator] Hergé was very careful in depicting a kind of reality that was around the 1940s,” explains Revelant. “Every element that was drawn in the book, we tried to find the respective real element from that period that could have been the inspiration for the Hergé drawing. Everything was checked against real period data.”
Creating the hair
Weta was working on Rise of the Planet of the Apes and Tintin at the same time. While the requirements for hair on Tintin weren’t anything near what they were for Apes, some of the aspects translated over. Tintin required wind effects, wet hair and a lot of development to get the hair to work coupled with the clothes.
Character hair in The Adventures of Tintin has to interact with objects and the environment
With the hat on, the Captain has a groom, styled so his hair doesn’t stick through the hat. When the hat is off, the hair is groomed appropriately. Sometimes the Captain put his hat on or took it off, so transitional shots with appropriate grooms were needed. The Captain’s hair ended up having a very dense particle set on the hair and collision objects with the hat, and his hair would spring up a bit during the transition.
Buy issue 152 of 3D World magazine to read the full article
Buy the Blu-ray of The Adventures of Tintin via Amazon
on Thursday, March 15th, 2012 at 1:59 pm under Features, Making of.
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Tags: making of Tintin, The Adventures of Tintin, The secret of the unicorn, tintin, Tintin animated film, Tintin movie, Weta Digital