JOURNEY 2 – ISLAND OF DREAMS

"'Journey 2' is above all intended to be a fun ride for kids," said Boyd. "We had a handful of conceptual illustrations and a few ideas for the core action sequences, such as the hurricane, the bee and lizard chase and the underwater sequence of the collapsing island - but no storyboards." Nevertheless, director Brad Peyton and the studio asked Boyd to create some very dynamic chase sequences the complement the story as it stood so far, in order to start giving the film that 'roller caster' feeling they wanted.

Previs allowed sequencing and planning the set pieces to fit within the budget, the story and to satisfy everyone's vision. Production designer Bill Boes became a close associate as did the director, editor and special effects crew – Boyd's key collaborators. The VFX and production design teams work from the same concepts, like the director, to create the film's looks.

Some sets were built entirely, others partly, some only minimally. In terms of environments Boyd's work has to coordinate what is built with what's expected. "For example, we used one very minimal set at the end of the film as the island collapses and the characters are standing at the edge of a cliff. "The entire set consisted of a table measuring about 10ft by 15ft, textured with a rocky surface – and no cliff at all. Fortunately, some photography had been shot at the location to base the VFX team's work on at Scanline in LA, but the full climactic environment then became their responsibility."

"Furthermore, concept designs like this tend to lack sufficient detail, such as small elements on the ship's exterior that give it realism. For coherence we usually go through the fleshing-out process alongside the Art Department."

Because Boyd's role included working as 2nd unit director, he focused intently on vendor selection. "I look out for teams with the strengths we needed for this project – creatures, environments, simulations and explosions, vehicles and so on. Actually, I'm doing this all the time whether I'm on a job or not. I keep up with what different vendors can do that is unique, different, better or cheaper compared to what other teams are doing. They are constantly updating their skills as well."

Sequence Design
"Then once I'm on a film, the better I understand the director's vision the better my choice of vendors will be. Sometimes, as on a large part of 'Journey2', the director's ideas are not concrete so I need to work with the previs artists, set up a digital camera and start designing action as soon as possible. Early sequence design tells the story, sets the energy beat and gives the editor something to work with."

Having sequence design in place gives everyone on the production a template with which to work. The production designer knows how much of a set has to be built, and the lighting department can design lights. Boyd was communicating with lots of people including grips, lighting, mechanical effects and more. He also continues to define with the director what the effects teams have to deliver. "Then I can motivate the artists to the bring life and something genuinely special to this vision, relying on their particular skills," he said.

All vendors had at least some environmental responsibilities, but he had selected a few of the teams specifically for their expertise. One of these was the team from Method Studios still known at the start of production as CIS Vancouver, where the artists had been doing some impressive environmental work. They created the City of Atlantis for 'Journey 2', a key place in the story. A section of this had been built physically outdoors on Oahu but the vast majority was fabricated in CG.

Catching Light
The outdoor shoot location meant they could use the natural light from Boyd's extensive HDR imagery. Boyd brought an HDR-Cam to all sets and used it to photograph the entire location. The camera system uses Light Engine software to automatically derive lighting information from the images that can in turn be plugged into the rendering environment to apply to CG builds.

This system helped especially during the bee chase sequence through the jungle, some portions of which were shot in a small, real forest in Hawaii. Boyd said, "I went up in a miniature helicopter to fly between the trees and up and over and through features to capture the sequence photographically as a foundation. Then I had to capture the lighting environment, and took the HDR-Cam into over 20 places within that forest to ensure that wherever the CG camera had to go later, the lighting would be correct. Furthermore on an earlier scouting trip, I had LIDAR scanned the entire forest.

Cameras Plus
"Over half a dozen different cameras were used. Defining the electronic workflow for that many cameras was complex. The primary cameras were the Sony F35. The production was gearing up at a time when the Alexa had just become available and Journey 2's producers were interested, but there weren't enough yet to go around, especially since many were in use on 'Hugo' in London. The RED Epics were also emerging but Peter Jackson was using several of them in New Zealand."

After testing the RED MX and a few other options, the production chose the F35. Some of the bee chase footage was shot on the F23. Boyd's aerial work often employed a RED MX, while for the mini helicopter forest shoot and the underwater eel sequence he used a pair of SI-2Ks. The Phantom was used generally used for slow motion.

The shoot lasted about 14 weeks – eight weeks in Hawaii, five seeks in North Carolina and a few days shooting pickups and elements in Los Angeles – and was one of the shortest feature films production schedules that Boyd had worked on.

Hurricanes and Giant Lizards
Because they were shooting some of their own reference photography for the bee chase sequence, Rising Sun Pictures were that only vendors that actually worked on set, and they were also the only team Boyd hadn't worked with before. The others, particularly Pixomondo and Scanline, were familiar with his thorough on-set data collection. As well as HDRI and LIDAR scans, they knew he would capture as many textures and measurements and so on as possible.

The lizard chase, early in the film, had some quite specific challenges. It had to be exciting but not threatening. I think MPC Vancouver's animation was an ideal balance. The lizard couldn't be treated as a giant dinosaur. It may have been 40ft long, but it had to remain lizard-like and integrate into a real jungle environment."

Two Worlds
The underwater sequence actually involved two aspects - the action above water as the island collapses, plus the activity below the surface where the characters swim into the cave and discover the Nautilus, interact with the sea life and then, as the island rapidly falls apart and sinks, they escape.

Each section involved a huge environment of its own. Underwater, the landscape is constantly shifting, moving and threatening the characters, obscuring the way ahead. Boyd said, "To avoid utter chaos through the sequence, the Pixomondo team approached it in terms of a video game, where you can see where you are going but the view is always changing and you have to react to each turn of events. Violent eruptions and falling rocks interfere with the ship's navigation. The ship has to feel huge but maneuverable through constant change and over a vast area of real estate that required a massive build out."

Because everything was in motion, virtually everything required a simulation, from the moving rocks to the silt, the venting volcanoes to the bubbles in the water streaming off the ship in trails. They needed hundreds of layered simulations.

One of Boyd's favourite sequences was small but significant, achieved by Trixter at the start of the island adventure involving some tiny but completely lifelike elephants, the size of an average dog. "When I first met Trixter, they had been working on cartoon animals in commercials, but hadn't ventured into any major photoreal creature projects. So I took the step of asking them to work at photoreal quality but to keep their distinctive character quality in their elephants, balancing between an elephant and a puppy-dog personality, slightly cute, almost smiling but not losing a true elephant's nature. It was just what we wanted in the end, but not easy to achieve."

Previs Edit
Boyd described the collaboration between editor Dave Rennie's editorial team and VFX as especially effective, fun and energetic, and started working with them during previs. "If the director says to me, 'I need you to create an exciting bee chase', but doesn't provide much else, I turn to the previs team and start building upshots and angles and devise a sequence that I edit myself first. Then I hand it to the editor and director and ask for further input, changes and ideas.

"The editor might add a character moment or insert a wide view, or come back and request extra shots I haven't provided. Also, as 2nd unit director, I was working with him during photography, and even more during post as vendors turned in material, providing much better quality footage to work with. We would discuss such points as the energy of the island collapse, for example, or speed of the ship and shot length, all affecting the cut."

The shots were captured in several ways, all in stereo 3D - with RED cameras, on tripods or hand held, as well as with the SI2Ks from the mini helicopter, flying through the forest. The footage began to trickle back to the team in Adelaide in about February 2011, which was also when 2D supervisor Tim Crosbie and Mark travelled to North Carolina to supervise the live action green screen portion of the sequence.

When building the CG forest, a major constraint was matching their forest to the existing footage, where the edit at times cut back and forth between the two. "It's quite different from an all-CG environment in a film like 'Avatar', which affords a lot of artistic freedom. While we had a level of freedom to enhance the forest, everything built had to be closely based on the real Hawaiian environment," explained Mark.

To that end, Boyd provided his abundant photographic reference, all plates, full HDRI stitched domes for lighting reference, and the LIDAR scanned data of the forest. It was incredibly heavy data, but turned out to be invaluable in a variety of ways.

Forest Build
"We built the forest in a couple of stages. The first was a low-resolution layout forest where all the action was plotted out. The production was especially keen on a few of The Third Floor's previs shots, so we replicated the camera moves of these precisely, beat for beat. But otherwise we had a fair amount of creative freedom to explore the action and dynamics, and the plotting and layout of the forest. It also gave us a chance to take advantage of the stereo and use trees and other forest elements whipping past camera to make the shots fun and immersive," said Mark.

The challenge of the stereo, of course, was that it couldn't be applied as an afterthought, especially in an action film where the studio wants the effect to be a highlight for young audiences. They had to be mindful of viewers' ability to resolve and perceive stereo images comfortably. As all compositing was done with Nuke, Ocula was used for processing the stereo plates. "This was a not-very-glamorous but very necessary part of working on this show. A huge amount of work and a substantial overhaul of our pipeline were needed to expand it and build a specific pipeline for stereo reconciliation – fixing stereo, vertical and colour disparities between the two eyes.

RSP also had to significantly expand their layout and camera team, not having worked on a project with the same scope or scale of environmental work as required for the forest and creatures in 'Journey 2'. A typical forest scene might have several hundred assets, initially hand placed by the layout team. Once the effects team had filled out the scene with extra foliage there would be thousands of individual pieces – leaves, trees, flowers, rocks, logs and so on. This meant developing some new tools, systems and processes in-house to manage the data.

Conceptual Undertaking
"On the camera side, we had to solve all the data in stereo. This became an enormous conceptual undertaking as much as a technical one," Mark explained. "We might have a shot involving a live action plate, shot independently in Hawaii from the helicopter with no motion control. Then several months later in North Carolina, the actors would have been shot on the bee-buck, our stand-in bee, in front of green screen, where the camera operator would attempt to roughly follow the camera action of the background plate. Our job was to marry the green screen footage of the actor, placed on top of our CG bee, to the background, shot with another camera, and then to make all of this work in stereo, ensuring that the depths and positions were all correct."

A full set of tracking markers would be in place on the green screen for the actors' shoot, while the bee-buck also had points allowing us to matchmove its motion as it rocked around fairly freely on a pivoting gimbal. So we had enough information to get good stereo matchmoves and camera tracks, as we had for the forest backgrounds. The challenge then was to 'float' the actors with their camera, with the camera of the background.

"This gave us our general approach - and our conceptual leap," said Mark. "We would set up a matchmove camera for the actors on green screen and that became one unit in a Maya scene file – a couple of cards with the actors on a plate, riding on top of a virtual bee with their tracked camera attached to them. Then we re-photographed that whole unit with the background's tracked camera. As long as we maintained a certain margin of proximity between the two cameras, we got away with a fair bit of disparity. In short, it turned out to be a workable system."

As it turned out, as they continued to explore camera angles and evaluate the photography, they transitioned to more and more all digital backgrounds. Mark believes that a major factor was some tests RSP's team had done earlier, closer the time when Boyd had shot the aerial forest footage. Boyd had originally thought of CG as a fall-back for where the live action was inadequate but the tests came back looking so good that, once they were in editorial, the production were confident about taking up the option to change some shots from the previs, moving the camera, extending the moves or altering speed.

"Sometimes we would use a background plate but then fly extra digital trees past in the foreground to add excitement and increase the feeling of movement," Mark said. "A further issue in the footage was that a small road, set with tracking markers, ran through a section of the forest. Also, on some helicopter shots the remote control operators were in view. So we had to devise a system for the stereo paint out and make sure it worked into the depth of each shot. With practice, the team got pretty efficient at these tasks."

RSP already had an in-house asset management system based on Maya for individual assets such as pieces of geometry, creatures, a shader or material. But up until then they hadn't developed any group assets, which they needed to create for 'Journey 2'. "We devised a layout asset which the new layout team used to hand place all the key trees and rocks in a shot, for example. This would be handed off to the animation department to help them plan the bees' flights around key objects in their scenes. At this level, layout and animation could be approved using grey-scale stereo renders out of Maya composed of naked trees as placeholders for the actors or CG to fly around," said Mark.

Physically Based Render
A second stage followed in which the effects team, working in Houdini, would used the layout asset as a start point for procedurally fleshing out the rest of the forest, filling out more trees in the background, thousands of saplings, ground cover, extra rocks and so on. They would create a series of low-res renders to approve this stage internally, and then go through another round for lighting. The lighting and final render could also be completed in Houdini through Mantra while all CG characters used Maya through 3Dlight.

One reason for the success of the forest was Mantra's physically based rendering mode, PBR. Mark explained, "We could use a fairly simple shading model for the foliage with a little translucence. A look development team painted numerous different textures for objects with bumps, displacements and specular maps. But the shading model in Mantra could remain simple as well as the lighting model, usually with just one key light, a dome and perhaps some hand-tuned dappling. But because of the way the PBR worked, we achieved the soft ambient light from the sky dome, bounce lighting from other objects plus the translucency from back-lit leaves.

When it came to the creatures for their sequence, production had a very clear idea of what they wanted for some, especially the giant birds which were modelled on the European Bee Eater. Rising Sun could use the birds' natural, lively colouring but had to enlarge its body from 6in to 40ft tall. They adjusted the markings and head shape to make the model look a little meaner, more wedge-shaped and hungrier, but the production mainly wanted to rely on its size to communicate any menacing qualities.

Just Plain Scary
The bees were to be rather cuddly, non-threatening and friendly, almost cow-like. RSP's production designer Nick Pil provided several concepts to production of how the bees might look, ranging from streamlined and waspy to bull-like, and even a few bees resembling motorcycles. They chose a balance between a friendly personality and real bee design.

"The spider, however, was intended to be just plain scary," said Mark. "We actually had to create two spiders for the film, both based on a similar model with a few distinguishing tweaks. The hero spider was involved in our main chase sequence, while an additional spider played a role in a shot as the camera pulled up to reveal him lurking in the canopy. The interesting part of the spider sequence was the web design.

"We were originally working off concepts from the client portraying a web that would completely shroud the foliage in a cheesecloth-like network. Everyone agreed that this would look appropriately creepy and it gave us a chance to build a network of tunnels and tubes in a sheet of hanging, dirty web. We spent a large portion of the production on it, testing ways to procedurally build the web in Houdini and making it dirty by hanging leaves and debris in it. We then draped it over, around and between the trees, over the ground and bushes."

It was effective, but had to be immediately identified by young children within a fast-paced action sequence. Also, to work with the edit, in which it is first glimpsed from a distance, this look just wasn't proving recognisable enough.

While the team's pipeline was based on Maya for character animation and layout and as an interface to the 3Dlight renderer, any simulations except cloth such as particles, dynamics, web movement and interactions were all done in Houdini, including wind through the trees and exploding feathers in the collision shot. "For actor-CG interactions, we created a rough rotomation of the live action to which the Houdini simulation could be synchronized – whether with foliage, the web or any other objects.

Double Excitement
Shots where the client was prepared to use an all-digital replacement such as characters falling from a bee through the forest canopy or the sky, generally required digital doubles of actors. There were further shots that needed enhancement or pickups from the live action to extend the shot, because of limited scope for camera moves and the green screen stage. Many of the long shots of characters in flight needed doubles as well.

These doubles were a challenge mainly because of the huge amount of extremely useful data from Boyd from several sources, including cyberscans but especially the normal maps from ICT, the Institute of Creative Technologies at the University of Southern California. "Once the ICT data was incorporated into our skin shader we could produce extremely accurate skin and digital doubles.

"Previously we had carried out skin shading in a more or less ad hoc manner, but this was the first time we had access to such high quality data. It took a period of R&D to incorporate using it into our process and get the results Boyd wanted. The data comprised specular and normal maps. Our character supervisor Ben Paschke and his team studied the papers from ICT intensely, plus the underlying mathematics of the data, developing it into a shading model that would work with the normal maps. The nice thing about the data is that once you get the shading correct, you get the expected skin shading components like sub surface scattering, multi-layered oily specular pore looks with soft reflective fall-off at the edges – all these qualities come naturally, due to the way this data is captured."

Dappling Effects
An effective way to make the bee sequence dynamic and fast-moving was the use of light as the characters zoomed in and out of shadow. On set the actors had some moving lights on them, but of a fairly low intensity, which needed enhancing to create the dappling effect of moving in and out of the light. "In the composite they lightened up or darkened down the light on the actors on cues from the forest lighting team working in Houdini and Mantra. The Mantra team could provide animated HDRI texture maps to be used as environmental lighting domes so that, for CG background shots, we could get perfect integration of lighting between the Mantra forest and the 3Dlight camera," Mark said.

"We would start with a physical approach to lighting, re-creating what the sun and shadow were actually doing, given the forest that they are moving through but inevitably, this wouldn't be exciting enough. We'd enhance that with extra dappling maps that the characters would fly through, just to keep the shot lively and flashing enough. Once the CG characters were handed over to compositing, and the live action characters positioned over them, the compositors would give final tweaks to match the dappled effect across the actor from the CG underneath."

A fairly automatic initial instancing system that put static feathers across the entire bird would follow any deformation of the underlying model. The primary feathers were actually exposed to animation and the lighters in the base geometry. The riggers put these into the rig so that the animators could access them as they posed the skeleton to strike dynamic poses or flutter.

For example, the first dramatic backlit shot of the bird attacking from the sky had a lot of character animation applied to the feathers for very specific poses and the slow motion rolling and ruffling. All secondary feathers could be applied with a procedural system. Once those were placed statically a character TD  would run a simulation on the m to put wind movement through them as well. All of this was then supplied to the lighters as an RIB archive.

"The fur system was not entirely new but we had to extend the automation of it for many shots," said Mark. "We used Joe Alter's Shave and a Haircut in Maya and added all the fur dynamics for interaction with that as well. But lots of work went into automating this so we could push a dozen simulations a day on a given set of shots through the render farm. The fur team handling the grooming were kept quite busy since every shot needed at least static fur on the bees for the longer shots, and interactive moving fur for closer looks. We used rotomated models again for the fur interaction with actors.

Selling the Scale
The main challenge for the animation team was selling the scale of the animals. "As we searched through lots of beautiful, slow motion reference of bees, and even found footage specifically of the European Bee Eater in flight, we meanwhile knew we would have to make the forest and animals feel extra large. The risk in that is making the humans look small but for this story, the characters had to remain feeling normal sized," Mark explained.

"So we played with various techniques to sell the scale of the forest and the characters. We played with stereo cameras to fine tune the interocular distance, the atmosphere and other aspects of stereo to enhance the scale. But the most successful techniques turned out to be animation. It took a lot of back and forth communication with the client to find that sweet spot where the bird moves just fast and aggressively enough to pose a serious threat, a monster on the verge of eating the characters."

But if they were allowed to move too quickly they started to feel cute and small again. The total performance of a big slow wing beat, the up and down motion of the body up and pivoting the head while tracking it with the body had to be developed through many cycles before Boyd and the director could find that spot where the scale worked.

It was the same for the bees. Obviously such a bee would be a heavy weight to carry on those wings but they developed a blurry wing bea, through numerous iterations with the right amount of motion, swinging and hanging the way real bees fly around, to sell it as something closer to the size of a car than a bee.

Mark and the team at Method has created just about every other kind of environment in films for specific reasons – a real place where a production cannot shoot, or a place that used to exist that they had photo reference for, or even an invented place with no references from reality. "In this case," Mark said. "Brad Peyton wanted a place that no one has ever seen before but, nevertheless, looks like somewhere you could go."

Like Rising Sun Pictures, Method found that Boyd's reference coverage of every shoot location on Hawaii was incredibly dense and thorough. Hawaii had been captured for them in full stereo 3D shots, LIDAR scans and more. But capturing that meeting point between fantasy and realism wasn't easy. Early in production, Method began creating and testing matte paintings. Overall, those early looks were effective but, as Mark explains here, they required numerous iterations, adding or removing trees, creating more elaborate rock waterfalls, until they finally arriving at the director's vision.

Illusion of Depth
Everything within that first reveal is based on studying real spaces that Brad and Boyd liked, taking from that data what was real to combine with the fantasy of the matte paintings, and bringing these elements together into a space people would believe long enough for that moment. The live action for the scene was shot on blue screen early on, long before anyone had decided what the island was actually going to look like. Therefore, the team took cues from the actors' performances and eyelines. They also built compositionally to guide viewers' eyes into the valley and down to a rocky arch and other story points in the distance.

"The combination of CG elements, matte paintings and stereo 3D creates a challenge," Mark said. "When you look at a 2D matte painting, depth is missing. You only have an illusion of depth as the brain goes to work making sense of the details. But putting that image into a true stereo space sends the brain mixed signals and the illusion fails. Overcoming this requires its own scene building process – and still more iteration."

"All these factors taken together helps the audience see what you want them to see," said Mark. "Our CG pipeline, based on Maya, wasn't unusual, but we were pushing Nuke's 3D space capabilities to their limit, and using Ocula for the stereo component within the composite to clean up frames and plates. Because stereo makes it hard to get good, matching tracks we used various matchmoving and tracking software including Boujou, PFTrack and Silhouette."

Mark explained why matchmoving was necessary on virtually every shot they handled. "In a 2D production, you only need to track the plate, which gives you a CG camera with which to build your environment for compositing. But for a stereo project, you need a stereo camera pair, achieved through matchmoving, that can be translated into a Nuke camera pair. All your small compositing tasks like wire removal, can't be done by painting a patch – the patch will simply hover in the air. You have to be able to do the removals in stereo, which can be accomplished in Nuke using projections and building a 3D environment, but you still need the stereo camera. That way, every render produces two images and all compositing jobs from clean up to blue screen comp, tracking and colour correction become possible."

Camera Data
Mark mentioned that having VFX producer Randy Starr to keep the time spent on perfecting the stereo part of the project within reasonable bounds was especially helpful. "It's extremely time-consuming work and has to be done well. Identifying stereo problems early is the key. Our team found we learned a huge amount about 3D tracking and matchmoves in particular on this show."

Every shot came with a complete set of metadata from the set including all camera data. This was obviously very useful but they found that it sometimes was not quite accurate or didn't fully record what was happening to the rig, such as the cameras' gradual shift out of position in terms of interocular distance and other values.

"The computer gives you its best estimate, but problem-solving is still up to you. About 50 to 75 per cent of the shots, about 50 in total, needed some special attention to work out the camera movement and replicate it in CG."

Mark is certain that when the opportunity to work on a stereo project comes up again, they won't hesitate to take it up. The team's head of matchmove Peter Hart put a great deal of effort into working these issues out and for Mark, making that effort worthwhile is the main reason to get involved with another project.

Stereo Bounce
In a humorous scene, the main character Josh throws berries at his muscle-bound step-father Sean, which bounce off of his chest. In this case, not only did the scene need matchmoving but the position of the actors' bodies had to be matchmoved as well. So when the CG berry is thrown, it leaves the 3D position of one actor's hand, flies up through 3D space, hits Sean's 3D chest position and then bounces back into the camera. "So the position of everything, including the camera, must be established perfectly. In a 2D film you would just track the single camera and composite in the berry, straightforwardly. But here, the berry also had to pop out of frame at the audience," Mark said.

Tree House
"In order to place the tree house accurately into the shots we also had to model the tree itself, to know exactly where it was in the plate," he said. "The house had to sit perfectly in 3D space, have depth and be viewable from every angle. Trying to model the tree from that massive number of points proved extremely difficult and if we meshed it, only the trunk and major branches were successful at first."

For the house itself the team were sent sketches and architectural plans of the inside of the set where the live action was shot. For this kind of architectural element Method uses a Maya – mental ray pipeline, and constructed the exterior based on these plans to ensure continuity from shot to shot.

To help them fit the resulting model convincingly into the tree, Mark and the modeller first built a support system for it to make it believable, complete with pulleys and ropes. "It went pretty accurately into the tree in the plates, although we had to remove a few stray branches poking up through the middle," Mark said. "Cutting branches off a tree in 3D space is a task I may not try again in a hurry."

Rocky Arch
On the beach after the characters' helicopter crash-lands onto the island, they are temporarily trapped by impenetrable cliffs looming on all sides. They only way to reach the island's interior is through a small cave. However, the cliffs in the plate were in fact much lower than in the story and only stood at the back of the beach. Boyd shot the location from a helicopter – a safer one - and supplied the team with 4K scans.

But later on, the very high quality data captured at ICT Light Stage of the actors made Method's exciting sequence at Spooky Bridge possible. This bridge is a precarious rocky arch where the actors couldn't actually go.  As the characters pass over it, the camera move and angle momentarily reveal a scary face designed into the rocks, and then the camera gradually passes by and lets the face disappear. But it also passes quite close to the characters.

Perfect Doubles
The skin textures, body dynamics and other information in the Light Stage data had every detail the modelling team could have needed for the doubles. The models were animated with motion capture allowing the helicopter with the camera to pass right over the top of the scene and stay focussed on them for several moments.

Mark explained, "Light Stage is a giant dome with scanning equipment that produces flat-lit character data that can be re-lit for different scenes in 3D. They output a model to animate with motion capture data, and provide the skin of the actor plus associated clothing. The amount of data they provide is huge, but essential to make the characters look real. We are, in fact, under pressure to put it all to good advantage. We communicated via conference calls with Light Stage to make sure we were setting up our render passes and so on correctly."

Actually, for this sequence, the first hurdle was the fact that during the shoot, the right eye camera came very loose, which made the stereo data inaccurate. They had to re-build the entire right eye plate from the left eye to be able to put in cliffs, rocks, characters - everything - into the shot. Next, they needed to design the right sort of 'scary face' as a spooky but believable rock formation incorporating stalagmites, stalactites, ivy overgrowth and so forth to suspend disbelief just long enough as the camera passes.

Ruined City of Atlantis
For the great, ruined city of Atlantis, the Art Department had provided drawings of an astounding environment that needed a lot of development before it could be effectively constructed. However, a number of practical set pieces of this city had been built for the shoot. These were ultimately what they used as the conceptual building blocks to design, shape and build out the city to match.

The basis of the city's design was a series of concentric circles, moving closer together to form a giant centrepiece.  The back story for the inhabitants of Atlantis involved managing and transporting the water supply as an explanation for this design. Mark noted, "These back stories are quite important for making sense of complex, fantasy environments. You ask yourself, how does it work? As a result, we were constructing sewage and water systems as well as houses and buildings. Then of course, we had to break it all to turn it into ruins!"

Early enough in the process they also needed to provide Scanline with a basic .obj model of the city to start work on their monumental flood waters. Later, Method was able to provide their model at higher resolutions with textures for Scanline to refine their simulation with. The city as built in space measures 3 to 4kms across, which immediately dwarfs the actors but gives lots of scope for stereo depth.

Another big challenge, however, came when putting the stone structures together with the overgrowing plants. Mark said, "We initially had a subroutine that laid plants over everything procedurally, which worked but didn't look very real. Plants of certain types will naturally grow in particular spots in cracks and so on, not randomly anywhere, and drop leaves in certain ways. Therefore, in the end, every plant was placed by hand. When the camera zoomed in, it made quite a difference to the believability of our shots."
Words: Adriene Hurst
Images: Courtesy of Warner Bros Pictures