Gulliver’s travelling mattes, green screen & fluid sims

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Gulliver (Jack Black) is working in the mail room of a newspaper and seems destined to stay there. Seeking to impress travel writer, Darcy Silverman (Amanda Peet), Gulliver accepts an assignment to cover a holiday location near the Bermuda Triangle. Here he is magically transported to Lilliput where he now exists as a 120 foot man amongst the Lilliputians. Eventually, Gulliver helps them overcome a long-standing rivalry with the Blefuscudian nation.

Central to director Rob Letterman’s premise for the comedy was a push for a lot of the humour to come from ‘scale’ jokes. Gulliver’s massive size compared to the Lilliputians, and, later, miniaturisation, was achieved mostly through visual effects. Jim Rygiel served as visual effects supervisor during principal photography, while vfx producer and supervisor Ellen Sommers came on later mid-way through post production. A global effort of vfx houses contributed to the show, including Weta Digital, Hydraulx, Scanline VFX, Method Studios, Pixel Playground, Tata Elxsi VCL and Geon, with the main and end titles by Rok!t Studio.

“When I came on,” says Somers, “the work had grown substantially from the original plan. I think there had been a thought to do a lot of CG environment work, but it became apparent that we really wanted to bring as much reality to the shots as possible. So many of the environments were accomplished by adding to the scenes shot in England (at Blenheim Palace in Oxfordshire) through matte paintings. But there were still many CG environments.”

Rok!t tilt-shifts the titles

Gulliver’s Travels opens with some innovative main titles completed by Rok!t Studio in which the names of actors and the filmmakers are incorporated into tilt-shift scenes of New York City. “Tilt-shift makes things look miniature,” says Rok!t visual effects supervisor Lee Nelson. “The way it does that is by adding depth of field. You get a lot of foreground blur and a lot of background blur and you’re just focused on a narrow piece that’s in focus.”

Rok!t filmed most of the New York backgrounds in stereo for the titles on dual Canon EOS 1D Mark IVs using a specially designed camera rig and a make-shift switch to override the camera’s automatic shutter so that the two cameras would be synchronised. A couple of shots were filmed on the Genesis camera. The tilt-shift effect was added in post-production by adding depth cues and appropriate blur.

For the various lettering, Rok!t relied on either matte painting or 3D techniques, often contending with moving people or traffic in the shots that had to be carefully roto’d so the shots would work in stereo. The film’s main ‘Gulliver’s Travels’ title that sits in Central Park was a combination of several images stitched together filmed from a helicopter, after it turned out the original shots could not be taken when President Obama’s convoy was in New York on the day of the shoot. Rok!t’s contribution to the film also included the final animated newspaper sequence that runs for the entire end titles.

For a more in depth detailed discussion of this amazing stereo title sequence – check out the separate fxInsider story – exclusively for fxinsider members as our way of saying thanks for your support.

Scanline delivers Gulliver to Lilliput

Embarking on his trip to the Bermuda Triangle via a pleasure craft, Gulliver soon finds himself in the middle of massive ocean storm. The storm effects, and a magical giant water funnel that is the gateway to Lilliput, were the work of Scanline VFX. “There were a few incarnations of the storm,” notes Scanline visual effects supervisor Bryan Grill. “Originally it was a whirlpool that sucked Jack Black down and then was more like a twister that sucked him up. In the end it became an erectile funnel of water that drags Gulliver up to the top and then swallows him, and then he awakens in Lilliput.”

Production shot footage of Jack Black on a boat that was on a gimbal and had a few dump tanks of water for the close-up water interaction. “This all was shot in London,” says Grill, “and was integrated with full CG water and storm environments at Scanline.”

The studio’s water sims for the raging ocean, interactive water and the funnel were achieved in its proprietary Flowline software pioneered by Scanline’s Stephan Trojansky, which runs through 3ds Max and renders out via V-Ray. A digital boat modelled from lidar scans and a digi-double Jack Black were also created to help achieve the shots. “One of the key things the director Rob Letterman wanted from the whirlpool storm sequence that Stephan and I worked on was to make Jack Black and the boat he was in seem very, very small in the vast ocean storm,” says Grill. “Part of making the funnel so big was to make Gulliver look small. This was a very important story point the director wanted to make because the next scene Gulliver wakes up and now he is the bigger than life.”


Scanline simulated the 500 feet high funnel in a way that made the water around it swell into its massive force. “We start out in one shot where we’re right there on the waves and then the funnel is sucking those stormy waters into it,” says Grill. “Originally it was a blend between two types of water but in order to pull it off at the end, it had to be constructed as one piece so you saw the waves being dragged and then you would see the details and the shape of the stormy weather as it was being sucked in. Our CG supervisor Danielle Plantec oversaw all of this work.”

One of the most challenging aspects of the funnel shots was making the water go fast enough but still have significant mass and scale. “We had to make the water faster but then add more details to make it look convincing,” says Grill. “It was a similar problem we faced on 2012. It came down to creating very minute splashing, movement and reflectivity and these types of things.”

Hydraulx orchestrates a robot duel

Hydraulx worked on 400 shots for the film, including several sequences around Lilliput, the rescue of Princess Mary (Emily Blunt), the parade and the giant duelling CG robot that the gilted General Edward (Chris O’Dowd) builds from plans he discovers in one of Gulliver’s magazines. Basing the robot on director and art department concepts, Hydraulx expanded the designs and conceptualised the robot transformation. “We took the basic silhouette and expanded the 2D design into a 3D object,” says Hydraulx visual effects supervisor Erik Liles. “We also had to work out how it all went together with the bolts, the gears, the pistons that actually drove this thing.”

Lead animation supervisor Randy Cook orchestrated the previs and final animation of the robot as it fights with Gulliver. The model was built in Maya and rendered in mental ray. “When the robot’s arms move, we added all these automated scripted events where the gears and pistons would move based on the animation,” says Liles. “We also built a proxy model of Jack and put his textures onto it so we could actually get his reflections onto the robot’s metallic surfaces, as well as the scene’s reflections.”

Jack Black was shot on greenscreen with a stunt double acting out the robot duel. Pieces of the robot based on the early designs were fabricated from foam and covered in blue material. “When Jack had to interact with the robot,” says Liles, “its mass was mimicked on the foam on the stuntman – so Jack could hit it and he would actually touch the actual robot’s chest and not the chest of the stuntman. There’s a scene where he jumps on the robot’s back and to shoot that he actually jumped on the back of the foam robot which had the right mass. Whatever parts Jack would interact with we would attach to our stuntman so Jack would always have a good physical model to deal with and help his interaction as well.”

Another significant part of Hydraulx’s work for the film included shots of the Lilliput version of Times Square that Gulliver has built. This represented his home city, but in a more Georgian style. “The art department laid out a design for which buildings were going to go where and what facades we wanted to use for each angle,” says Liles. “Then we went down to the banking district of London and lidar’d a bunch of the buildings there to use as the basis of the city. We had to re-model and manipulate them to fit them in.”

To insert the Lilliputians, actors and extras were shot in an open parking lot lined with greenscreen for the foreground. Jack Black, who needed to stand 120 foot tall, was shot on green with a matching angle, with the 3D buildings dropped in. On other occasions, shots of Gulliver sitting amongst buildings were filmed with Jack Black interacting with grey proxies of the actual set. “This meant the shadows would cast properly onto him,” says Liles, “and he had something to lean against or put his hand on.” Other times a slaved motion control rig was utilised to film both the little people and Jack Black at the same time in the same outdoor lighting.

Walking through Lilliput with Method

Green screen and tennis balls helped with eyelines

Method Studios delivered ten shots for a sequence in which Gulliver and Horatio (Jason Segel) walk through Lilliput. Using a combination of CG environments and live action foreground photography, Method visual effects supervisor Sean Faden oversaw the completion of the complicated shots in a mere seven weeks.

“The most challenging shot begins the sequence as a camera tilts down off the sky to find Gulliver walking amongst a fully CG environment including a digital double of Horatio,” explains Faden. “We started with modeled assets from another vendor for the foreground building which Horatio is running on, and created our own textures and V-Ray lighting pipeline for rendering hero buildings and the CG Horatio running across the rooftop.”

Animator Steward Burris studied some Jason Segel performances and then filmed himself sliding down a large skateboard ramp and landing in various ways. “It was great reference and helped them nail a tricky animation in a relatively short amount of time,” says Faden. “The other buildings and background were created by Method based on work by matte painter and concept artist Olivier Pron. It was important for production that the Lilliput world feel real and real scale- not miniature. Method took inspiration from a vast library of images of Oxford, England provided by production.”

The final shots utilised Nuke’s 3D capabilities to project multiple matte painting layers and various lighting passes on simplified building geometry. “This was combined with V-Ray renders for the foreground building and Horatio and carefully composited to integrate Gulliver with the CG environment,” notes Faden. “One trick which helped here was using V-Ray created GI renders to cast red from Gulliver’s t-shirt on the surrounding buildings in addition to reflection and occlusion passes generated by the CG artists. This hero shot set the tone for the other angles in the sequence, and matte painter Justine Gasquet contributed concepts for additional shots. Subtle movements were added to trees and skies using warp tools within Nuke.”

Utilising Weta’s full armada

Lilliput Times Square

Contributing around 170 significant effects shots was Weta Digital, which handled the initial shots of Gulliver waking up in ropes on the Lilliput beach, a similar shot of Darcy later in the film, the huge marrionette-like exoskeleton made to control Gulliver, scenes in Lilliput Times Square and the armada sequence in which Gulliver takes on a massive fleet of invading ships.


“That armada scene was the hardest work we did since it involved complicated fluid sims and was just about all shot dry,” notes Weta visual effects supervisor Guy Williams. “About five of the shots were done with real water but of course it was the wrong scale and there were some pretty gnarly paint-outs to remove water splashing in front of Jack Black’s face and replacing it with water that was the right scale.”

The actor was filmed against a bluescreen performing his actions for about two-thirds of the sequence, and then also in water against bluescreen for the remaining shots. “The good thing about the wet plates,” says Williams, “was that at least they got him wet – the bottom half of his body was glistening and that helped those shots along.”

Apart from shots at ship deck level – a live action set – all of the armada and surrounding water and sky was created digitally by Weta, with Jack Black added in. The studio continued using Exotic Matter’s Naiad for fluid simulations, used previously on Avatar, in conjunction with its proprietary Synapse system. “For example,” says Williams, “when Jack Black’s arm moves through the water, not only does it push the water aside, it also creates a beautiful cavitation effect behind the arm with all this aeration in the water and splashes.”


Synapse allowed Weta to integrate fluid solves together by taking multiple data sets and merging them into one. “On one shot where Jack rises up out of the water and the water cascades around him,” says Williams, “we ended up doing two or three different fluid solves and merging them together to get them to the right kind of scale but also the larger forms. It allows us to not to have to do a single ‘billion’ voxel simulation – you can do a handful of them and merge them together and get something that looks like a very complex simulation. It also allows you to take the solves out of Naiad and create particles on them and then run solves on those particles and integrate it all back into the original solves.”

The final shot

The armada ships were based on a model provided by Hydraulx that Weta adapted for its pipeline. Each ship had three masts that each had three sails, all of which were individually simulated. “We made really high-res cloth meshes,” says Williams, “and set up a script so that every single set of sails was simulated. We didn’t have to run that in one simulation and have it take the better part of two months – we were able to throw it on the render wall and have it finished in about six hours.”

“That was a really important step for us because it meant we didn’t have to cut corners,” adds Williams. “We didn’t have one sail simulation that we just cloned onto every boat. Every boat had its own unique animation and that animation affected the sail simulation, which was really high resolution so that all the wrinkles and collisions with the masts is captured properly from ship to ship.”

Sailors seen on the decks in wider scenes were created in Massive and rendered in RenderMan. Shots of the wooden ships being destroyed relied on Weta’s incorporation of the Bullet open source physics engine into its system to deal with planks and other objects splintering. Animators also keyframed people and cannons being flung in the air. The cannon shots themselves were achieved using fluid solvers. “You actually see the nice flash with the puff of smoke that travels in the mushroom shape from each canon,” says Williams. “Then if we had to do speed ramps, the bullet shots go from being really fast to going through slow-moving clouds.”

Further destruction ensues when canon balls are repelled by the Gulliver’s large belly. “Initially we were given a plate and we looked at that and noticed they were using the Phantom high speed digital camera which is known for having a very shallow depth of field,” notes Williams. “So of course half of his belly is out of focus which made it feel like it was a little small and a bit out of scale.”

To solve the depth of field, Weta created the belly digitally, initially rotoscoping the animation from the plate and then adding to the performance. “We keyframed the overall motion of it including the lift of the belly,” says Williams, “and then we used some of our new tissue solving software where we actually created a fascia layer and could specify how thick the various parts of the belly were. It’s using the proper rigidity of the tissue, so it’s true volume-preserving but it even goes so far as to have grain and densities right. We used that to create the secondary motion of the belly which gives you all the ripples and the underlating fat feel to it. Then we textured it up to the tenth degree and rendered it.”


In addition to the heavy visual effects work, Gulliver’s Travels was also post-dimensionalised for stereo release, with many of the vendors able to provide mattes and z-depth renders to assist that process. The key, though, was achieving the right scale for Gulliver and the Lilliputians throughout the film. “Little people are pretty straightforward in the sense that it’s all mathematics,” says Ellen Somers. “Visually, the more difficult work was in the scaling of the water, particularly in the armada sequence. We had to visually define what a 120 foot man would look like when he was splashing around like he was in a bathtub, and Weta did such a great job. There were times when science is great and can be perfect but it doesn’t necessarily tell the story the way you want to.”