Giant Footsteps
Issue: Volume 37 Issue 1: (Jan/Feb 2014)

Giant Footsteps

Often writers find themselves walking in the steps of literary giants. The same holds true for directors, artists, and animators, especially those working on the Walking with Dinosaurs feature film. Not only did they have to live up to the high standards set by the BBC on the six-part documentary miniseries by the same name, but they also had big footprints to fill with creating realistic CG dinosaurs and inserting them into live-action backgrounds – for the stereo 3D production.

The feature film, directed by Barry Cook and Neil Nightingale for Twentieth Century Fox/Reliance Entertainment and BBC Earth/Evergreen Films, takes audiences on a journey back in time to the latter part of the Cretaceous Period, where viewers encounter the young Patchi (a Pachyrhinosaurus) and follow him as he grows up and struggles to survive during this evolutionary time period.

The adventure is set 70 million years ago in what is now Alaska. It stars computer-generated dinosaurs created by Animal Logic that had to be realistic enough to fit naturally into live-action backgrounds. “Walking with Dinosaurs is a story about a dinosaur’s life and adventures, and we’ve gone to the ends of the world to film it,” says Cook (Mulan, Arthur Christmas, Aladdin, TRON).

THE ENVIRONMENTS in the film are shot live action with three exceptions, including this scene as the dinosaurs traverse the frozen lake.

Cook’s digital vision is complemented by Nightingale’s ability to capture nature’s wonders in unique ways. “Life’s fundamentals have not really changed since the time of the dinosaurs,” says Nightingale, who is creative director at BBC Earth, where he spearheads development of new forms of commercial content. “Thankfully, we don’t face perilous pursuit by hungry Gorgosaurs [as do the characters in the film], but audiences can identify with Patchi’s quest for survival. We meet him as a hatchling and watch him learn to navigate his environment and face the primary challenges of finding enough to eat, evade predators, and rise above his rivals in order to win a mate.”

Marco Marenghi, Animal Logic’s animation director on Walking with Dinosaurs, credits two rendering breakthroughs as being “game-changing” in the studio’s ability to bring the realistic CG dinosaurs to life in what amounted to more than 800 animated shots. “The two big ones,” he elaborates, “were the skin/scale system and the muscle system our team of character setup artists created for us, which enabled us to show how these amazing creatures were built, moved, and interacted.”

Story Evolution
The BBC’s 1999 award-winning TV production brought realistic dinosaurs to life in a nature-style documentary where the only voice was that of the narrator, Kenneth Branagh (for the UK) and Avery Brooks (for the US). In other words, the dinosaurs did not speak, which made them all the more believable in the series. In this latest project, the characters’ mouths do not move, nor do they speak per se. An Alexomis bird name Alex (John Leguizamo) serves as the film’s narrator, telling the story of the three main Pachyrhinosaurs, although the beasts can be heard in voice-overs expressing their thoughts, in a move to make what was originally a silent film more accessible to children.

While there are many similarities between the television series and the film, there are just as many differences. And, according to Animal Logic’s Will Reichelt, VFX supervisor, the film – while an extension of the TV series – was devised as its own project. “We were approached by Evergreen Films and the BBC with the idea of doing a dinosaur movie in 3D. There wasn’t any script, and we were brought on to help discuss the idea and develop it,” he says.

As a result, the studio was involved from the early stages with the evolution of the story and characters, and worked with paleontologists to ensure that the information being presented was scientifically accurate and sound. David Krentz also worked with scientists to create designs for each of the main species, which he then handed over to the team at Animal Logic to base their models on (see “Dinosaur Designs,” page 28). From there, the crew started working on character development and scene previs.

THE ARTISTS WORKED with paleontologists to create realistic and scientifically accurate models.

“Our goal was to be as photorealistic as possible with the creations and as scientifically accurate as possible,” says Reichelt. As is often the case, the BBC selected lesser-known but interesting species for the movie, and put the CG artists in touch with the leading relevant paleontologists and experts so the modelers and animators had the most extensive and up-to-date information to make the most realistic versions of the characters – realistic in terms of scientific accuracy and aesthetics. To this end, the scientists provided substantial data from fossil finds, papers, and other sources on skeletal reconstruction, muscles, skin definition, and more, which Animal Logic used during the modeling phase.

“Paleontologists helped us work out how all the characters would move. Fossilized footprints provided the speed at which they could travel,” says Emmanuel Blasset, CG supervisor. “The [scientific] information was not just about fossilized bones and skeleton reconstruction, but also provided insights to surface detailing, such as the use of feathers or scales, as well as animalistic behaviors based on migration paths and so forth. The most up-to-date paleontological research was the starting point for designing each creature on the film.”

Digital Dinos
In addition to Patchi, his brother and rival Scowler, and their herd of Pachyrhinosaurs, the film features a number of other species, including the large duck-billed Edmontosaurus, the small lizard-like Parksosaur, the smaller-yet Hesperonychus, the bird-like Alexomis, the T. rex-on-steroids Gorgosaurus, the feathered Troodon, the webbed-wing Quetzalcoatlus, and more. The species in the film vary greatly in size, shape, and look, presenting a challenge for the Animal Logic crew. In all, there are at least a dozen main species – 10 of which are scaled and two feathered – as well as many variations of those species.

“We wanted to transport audiences back to a real world, to meet dinosaurs that truly existed, and to immerse audiences in that world,” Nightingale says. “For a big motion-picture experience, it’s also vital to have a strong and emotionally engaging story. So we used what we knew about Late Cretaceous Alaskan dinosaurs as inspiration for a fictional, character-driven story that would entertain families.”

Directing the Animal Logic animation team was Marenghi (Alice in Wonderland, Minority Report), who was one of the original animators who worked on the television series. The modelers began with Krentz’s initial Pixologic ZBrush sculpts, then extracted the topology and did the final tweaks in Auto­desk’s Maya. Each model contains an average of 70,000 to 100,000 polygons – that is, before scales were added. Millions of scales.

Animal Logic developed a number of tools that helped push the boundary of reality in the film. The artists used a procedural- rather than textural-based approach to the scales. Instead of painting them on or modeling them individually, they opted for a technique that was similar to what they used to create fur and feathers, “where we use a lot of maps to describe the kind of scale in different areas of the body in terms of shape, size, profile,” explains Blasset.

To this end, the studio developed a scale system, called Reptile, under the supervision of Look Development Super­visor Jean Pascal Leblanc and R&D Lead Daniel Heckenberg.

The main surfacing challenge for the prehistoric cast resulted from the scale-based characters. “Commonly in movies, dinosaurs have leathery skin because it is simple to texture. When the leather stretches, you accept the stretching as part of the surface. The paleontologists said they were tired of seeing leathery-based characters and wanted more reptilian, scale-based surfaces,” says Blasset. “But the challenge with reptile-like surfaces is that you have to model, surface, and deform each scale separately to the skin lodged in between, since you need to be able to stretch and compress the skin rather than [stretch] the scales.”

As a result, the artists produced a very subtle effect for the area between the scales. The results are front and center in one shot, an extreme close-up, where audiences can see the ripple of the compression due to the stretching of the skin as the beast blinks.

Just how many scales are there on a character? “To extract the maximum level of detail in the render, you are talking about hundreds of millions of polygons on each character. We stopped counting scales after a million,” says Blasset. “If you look at a character full frame, individual scales can be distinguishable. But with all the deformation around main articulations, skin folds, mouth, and eyes, tiny scales had to be introduced as well – we are well into the millions.”

The artists made subtle tweaks here and there, particularly with patterns and color that helped define the texture maps laid on top of the scales and on the skin. “We dealt with many specific markings to distinguish the main cast. When you deal with a lot of characters and species on screen, you need to be able to recognize one character from another, from a storytelling standpoint,” says Blasset. “A lot of time was spent designing and surfacing, giving each character individual markings and [a unique] palette.” Variations were also made to the Pachyrhinosaurs’ horns and frills. In fact, the hero Patchi has a unique marking – a bite hole on his frill – that was introduced early as a story-driven element, so he can be picked out of the crowd easily in large-herd scenes.

Reptile Run
Understandably, keyframe animation was used to make the prehistoric characters move, whether trotting, running, or walking. The crew devised the animation rigs in Autodesk’s Softimage XSI, which enabled them to quickly define the characters and setups, along with variations of the rigs that were propagated across an entire species. Animators spent the time early on defining motion cycles, so the first stage of animation involved assigning and adapting the cycles leading up to a shot and defining the animation path.

Key to the animation was a new muscle system, dubbed Steroid, which enabled the team to push the results beyond what they had achieved in the past. “Muscle systems are difficult. Some companies often go back to a traditional blendshapes approach to mimic muscles,” says Blasset. “Typically, it is difficult to get stable results out of a muscle system without a lot of shot-based tweaking.”

ANIMAL LOGIC USED a procedural approach to add scales to the reptiles through its proprietary Reptile system.

Rigging Supervisor Raffaele Fragapane and R&D Lead Aloys Baillet came up with the brand-new system, which properly managed individual muscles and bones, and provided interaction with the outer skin and internal fat. The process was completely transparent to animators and did not require shot-specific adjustments. “The bulk of our cast is very muscular, and you have to be able to see the ribs poking out when they breathe and read the effects of the skin sliding on top of bulging muscles,” Blasset says. “We had to put a lot of surface detailing on our creatures, but it was equality important to deform them realistically.”

The animators could load a shot, and the rendering system would implement the muscle tool. The animators could then quickly see the results – what the muscles were doing in relation to the motion – and refine the motion easily.

For rendering, the studio used Pixar’s RenderMan and Animal Logic’s proprietary Maya-to-RenderMan software called MayaMan. According to Blasset, a typical final animation render for this project took approximately 100 hours per frame.

Lighting Supervisor Max Liani and Associate CG Supervisor Steve Agland revisited the studio’s lighting and shading pipeline with a physically plausible lighting and shading approach. “From the ground up, it provided a photorealistic look and showed all the detail we created on the characters,” Blasset says.

To ensure that the CG characters blended seamlessly into the plates, the team captured HDRI images on set for just about every shot and implemented those into the physically plausible lighting and shading pipeline. “That gave us a very solid base for lighting the characters right out of the box, and gave us a very realistic view of what the characters should look like and gave the lighters more time to focus on the artistry,” says Reichelt.

On set, the filmmakers mostly used natural lighting. “Often ‘out of the box’ was the most realistic but not always the prettiest. Usually we spend all our time trying to make things look real, so this gave us the time to get the reality first and more time getting it to look good,” adds Reichelt.

The crew also captured survey data, collecting points to determine where the cameras and lights were on set.

Cretaceous Environments
Reichelt estimates that approximately two-thirds of the backgrounds in Walking with Dinosaurs are live action; nearly a quarter are all-CG, while the rest comprise both CG and live action. Filming involved three separate shoots, with the initial one occurring in June 2011 in Alaska, with a follow-up there in October 2011. The main filming was done in New Zealand from February to July 2012.

The all-CG backgrounds, which entail a few hundred shots, encompass three different sequences, including the showdown in the forest between Patchi and his brother at dusk and later at night. Another sets the scene when the herd must cross a frozen lake surrounded by mountains. In the sequence, the herd is separated into two different groups and then reforms after the beasts cross the lake. It is about the changing of the guard and how the hero manages to reach his full potential. When they meet up again at the end of the lake, all hell breaks loose. “The decision to use CG for the ice and ice breaking, as opposed to a real location, had more to do with the complexity of the interaction between the dinosaurs and the environments,” says Blasset.

According to Nightingale, the dinosaurs had to interact with the ground, so the CG artists created the computer-generated ice. “This was the most effective way for us to get our dinosaurs to interact and fight, ensuring that their fall through the ice looked and felt realistic in keeping up with the dramatic pace of the movie,” he says.

IN ADDITION TO the scaled dinosaurs, there were two species requiring feathers, resulting in heavy models throughout the scenes.

All the CG locations were derived from actual locales, and the showdown scene is based on a site in Primrose, Alaska, with gnarly tree stumps pushed out of the ground and washed over and smoothed with water and rocks. “It looked very prehistoric,” Blasset says.

All the locations have a Cretaceous aesthetic and resemble the dinosaurs’ original habitats 70 million years ago. “The intention,” says Nightingale, “was for Walking with Dinosaurs to look as though a real wildlife cameraman had gone back in time to capture the footage. So we found locations, as closely as we could in the modern world, that would replicate Arctic Alaska in the Cretaceous Period.”

In the digital scenes as well as those containing live-action plates, the objective was the same: to make them as real as possible. To this end, it was imperative to match the level of detail in the CG to that in the natural environments, which are rich with color and texture. “We had to take both the creatures and the environments to a level where they would fit with the live-action plates and audiences wouldn’t question it,” says Reichelt.

To tie the characters into the live-action plates, the crew scanned the locations with LIDAR (Light Detection and Ranging). LIDAR uses light pulses to find distance information about environmental objects. The information was also used for previs: framing and editing, and determining camera angles. Indeed, LIDAR technology has been used for years in CG shots to capture backgrounds, but never before for nearly an entire movie, as it was here. “You will be able to see that this process brings an entirely new level of realism in contact dynamics as the characters interact with each other and their world,” says Mike Devlin, CEO of Evergreen Studios.

On set, the group used dinosaur stand-ins made with PVC pipes to be sure the characters would fit properly in the shot once they were composited with The Foundry’s Nuke. “We needed to validate on set. For instance, we needed to know we would be able to insert three 15-foot-long dinosaurs in a plate, and for every shot, we had a procedure where we would set up the PVC dinosaurs and walk them through their paces. We made sure everything would work once we got back to the studio,” says Reichelt.

Further establishing the CG into the shots required dynamic interaction between the digital characters and the environments, and footfalls were an important part of that as the characters kicked up grass, rocks, dust, and debris while running, as were the splashes and spray when the beasts fell into the water. “We auto-generated footprints and then used them to displace the ground with just the right pressure,” explains Reichelt. “When the characters are running on soft sand, we have clumps of sand coming off the feet. We had contact points and generated a map. Sometimes the feet connected cleanly, sometimes not, but [the map] at least gave us when and where the contact points happened so we could work out how best to show the interactions.”

There is a plethora of effects, generated in Side Effects Houdini and other software, that help sell the interaction between the CG characters and the real environments.

In 3D
The characters in Walking with Dinosaurs are large and fascinating. And because they are shown in stereo 3D, their presence was even more commanding on screen. “Stereo 3D was a consideration at every step in the process,” says Reichelt.

Animal Logic partnered with 3D production and technology specialists Cameron Pace Group (CPG) for the 3D. The stereo plates were shot using CPG’s Fusion Camera System and tracked using the LIDAR scans.

WALKING WITH DINOSAURS follows Patchi, a Pachyrhinosaurus, as it grows from a hatchling into a herd leader. The film also features several other lesser-known but interesting dinosaur species. 

According to Blasset, framing was a big consideration on location in terms of the stereography. Performances were reassessed within the stereo volume. Dailies were reviewed in stereo. Every element was examined.

“Stereo is unforgiving if an element is slightly off,” says Reichelt. “It changes the way you frame shots and perceive the characters. When you play with interocular distance and convergence, whether something is pushed to the back or brought forward, it has an impact on the story. How you continue the stereo from one shot to another also has an effect. For instance, in the scene when the main character falls into the river, the director wanted more depth, more impact. So by increasing the interocular distance on those shots, we travel with [Patchi] in the water, and the audience is more immersed in the environment and not just looking at the screen.”

The journey back to prehistoric times was a long one for the Animal Logic team in Sydney, which collectively numbered 300. All told, they spent three and a half years immersed in the Cretaceous era, starting with an early test in mid-2010 to prove the concept of photoreal dinosaurs in live action.

While Animal Logic has created CG characters for movies such as Legend of the Guardians and Happy Feet, that work was more stylized. With Walking with Dinosaurs, the artists accomplished an evolutionary step from cartoony to photoreal. And they achieved this in a big way, walking in the footsteps of the prehistoric giants they brought to life on the big screen.

Dinosaur Design

Longtime dinosaur artist and enthusiast David Krentz (Fantasia 2000, John Carter) created the character designs for the film. He has extensive experience hatching a range of prehistoric beasts for several dinosaur-themed movies, including Disney’s Dinosaur, Dinosaur Revolution, and Dinotasia, but he still spent countless hours with at least five paleontologists before reaching the final look for the characters in Walking with Dinosaurs.

“I had to keep them in the world of realism, but at the same time caricature them enough so audiences could tell the differences between the characters on screen,” says Krentz. As the movie developed, so did the characters, requiring the designer to make slight evolutionary changes to the designs that made them slightly anthropomorphized and appealing to young viewers.

Nevertheless, Krentz’s designs still had to adhere to the standards set by the scientists: make them as accurate as possible based on the fossil evidence available. To this end, he conducted his own research and was provided up-to-date information by the paleontologists.

Krentz modeled the dinosaurs in Pixologic’s ZBrush after first making pencil sketches. “I used to do orthographic drawings, which is what I did for the Disney dinosaurs in 1996. But with ZBrush, I can get all the hidden areas right away and communicate [the design] very quickly,” he explains.

Krentz designed the main character species and their variants, including juveniles. “The cool thing with ZBrush is that you can do variations quickly and get those in front of the director,” he notes. Later, Animal Logic transformed the sculpts into the animated models that eventually appear in the film and populated the environments with additional members of the species.

The Pachyrhinosaurus provided a wealth of design opportunity due to the shape of its skull and horns: This natural ornamentation enabled the artists to individualize the creatures while adhering to their mandate of “keeping it real.” For instance, the horns could vary in size and shape. They could be bent forward or backward. Nose bumps could be made rounder or sharper. The personality of the characters also played a part in Krentz’s design. He used circular shapes for the hero Patchi, while Scowler was crafted with triangles and parallelograms to make him appear sharper, more edgy. For the female Juniper, the artist used soft-baked triangular shapes to giver her a more feminine feel.

During the design phase, scientific information about the Pachyrhinosaurus was still being unearthed, and the scientific expert was prepping newly excavated fossils. “We were going back and forth on what the face looked like, things like that. But [the paleontologist] had enough information to make sound, educated guesses,” says Krentz.

Even though Krentz had visited the prehistoric period many times before, he never tires of creating dinosaurs. “This was a dream project for me. It’s very rare in one’s career to get a project like this,” he says. – Karen Moltenbrey

Karen Moltenbrey is the chief editor of CGW.