Animation: Disney-Pixar's <I>Luca</I>
Issue: November/December 2021

Animation: Disney-Pixar's Luca

We all know someone in our life who pushes us beyond our comfort zone, to try new things, even when that little voice inside our head tells us we can’t or we shouldn’t. Enrico Casarosa, director of Disney•Pixar’s Luca, is not one who is afraid to try new things. Casarosa, inspired by his own childhood on the Italian Riviera, challenged the studio’s celebrated masters of the 3D animation domain, to try something different for Pixar’s 24th feature release by incorporating a 2D cartoon aesthetic within Luca’s 3D structure. Indeed, a fish-out-of-water story. In more ways than one.

In Luca, young, shy, introverted, rule-following 13-year-old Luca is befriended by free-spirited teen Alberto, who introduces him to the “finer” things on land, as the two spend an unforgettable summer on the Italian Riviera living a carefree, adventurous life as two young boys should. 

However, these two young boys have a big secret: They are actually sea monsters. Above water, they appear human; below the water (or wet), their true nature becomes apparent. Living this double life is risky, as the local human townspeople are often on the lookout for sea monsters after years of reported but unsubstantiated sightings. Despite warnings from his parents, Luca, along with his friend, are determined to enjoy the human world filled with gelato, pasta, scooter rides, and more.



The Vespa-obsessed Alberto has been living above the surface for some time, and his exaggerated knowledge of this unique world impresses his newfound friend. “Alberto literally drags Luca out of the water, and we discover that these sea monsters have the magical ability to transform into human form when they’re dry. The inspiration [for the sea monsters] was sea life, like octopuses, which are able to camouflage and change the way they look,” explains Casarosa, who also had a friend like Alberto who pushed him beyond his comfort zone while growing up in Genoa, a port city on the Italian Riviera. In fact, the character Alberto is inspired by Casarosa’s own childhood friend, also named Alberto.

The film invokes a feeling of nostalgia through its warm, painterly, watercolor style and whimsical animation. While the goal was to give the film a timeless look, the story is set in the late 1950s/early 1960s during the Italian “Golden Age” of cinema and music — a period Casarosa is particularly fond of (despite growing up in the 1980s). And, there are homages to those period movies in the form of posters and signs throughout the CG town. 
“The towns [around where I grew up] are stuck in time; they’re so picturesque,” Casarosa says.

The watercolor aesthetic carries with it 2D influences, giving the film a highly stylized look, especially compared to the more realistic CGI typically exhibited in a Pixar film. Looks can be deceiving, however. This is a 3D film, although rather than having everything appear straight, even, and realistic, as computers are tuned to do, the filmmakers wanted Luca to be caricatured and imperfect, so you can feel the hand of the artist. 
“The most technically challenging part for us was achieving the visual style that we wanted for this film. It is something that’s very different than what we’ve done in other Pixar movies,” says Character Supervisor Beth Albright.

It might be different compared to the studio’s other features, but the underlying aesthetic is actually an expansion of the look Casarosa used for his coming-of-age short film “La Luna.” Casarosa’s film style is influenced by Japanese animation and artistry. “[For Luca] Enrico would draw these sinuous, simple shapes of reflections in the water that looked like traditional woodblocks,” says Production Designer Daniela Strijleva. “With that in mind, we were challenged with simplifying the look of a 3D film, which was super fun to do, hitting a certain level of caricature that’s true to Enrico’s style. It’s very expressive and lyrical.”



While the film contains a high degree of 2D influence, Casarosa made it clear that he wanted to create something new and different for Luca. “He was very specific that it shouldn’t look like stop-motion, anime, or anything else, and that we had the power of the computer with us, so we could create something new. And that’s something we like to do at Pixar,” says Character Supervisor Sajan Skaria. “While we were inspired by all of that, we had the tools to craft it our way.”

Diverse Cast of Characters

Luca has a wide range of characters, some of whom live underwater and others on land.

Luca’s family are sea dwellers, creatures inspired by depictions of sea monsters found on old maps from the Renaissance, as well as scientific illustrations of fish from the region in addition to Japanese dragons and serpents. In fact, different types of fish were used as reference for the characters in different ways. For example, a larger silvery fish, like a big tuna or barracuda, was used as a reference for Alberto. A more colorful species, such as a reef fish, was used for Luca.

“We looked at marine iguanas because of the way they swim underwater and use their limbs, and their tail is really interesting and different from the way another type of reptile might move or swim,” says Albright. As a result, the sea monster versions of the boys are more creature-y and less humanlike when they swim. “We combined all of these different influences to make our sea monsters really unique,” she adds.

The artists also had to ensure that the underwater animation illustrated drift and water resistance. “The characters couldn’t stop too abruptly in the water, so they would hit a pose and then float a little, letting the energy dissipate into the water and slowly come to a stop,” Michael Venturini, animation supervisor, explains.
The creatures, which are hardly monsters, are appealing and expressive, each playing a stereotypical family member role. Daniela is Luca’s overly cautious mother, whose number one rule is not to go near the water’s surface, where land monsters supposedly live. Lorenzo, Luca’s dad, is often distracted by his hobby of raising prize-winning crabs. Grandma, meanwhile, understands Luca’s yearning for something more and secretly supports his adventurous ambitions.



The people in the town of Portorosso are representative of those found in a typical small town. In all, the artists created 56 individuals for this film, some main characters and others relegated to the background. “This is one of those movies where we’re not literally just populating the entire place with a bunch of characters. We know them,” says Albright. “It’s like each one was handcrafted. We spent time with them, and that quality shows on-screen.”

Ercole, a blowhard, is the town bully who likes to target Giulia. He also owns a shiny Vespa and is the repeat champion of the town’s Portorosso Cup race, which Giulia longs to win. Giulia is friendly and adventuresome, though she does not have many local friends since she is a summer resident who lives there with her divorced fisherman father. So, she quickly befriends the two strangers — Luca and Alberto — who suddenly appear in town. 

Monster Mash

The main characters, Luca and Alberto, presented an even bigger challenge for the character artists and animators due to their ability to shape-shift. In some shots, these characters appear in blended form. “It took us about a year to figure it out,” says Skaria of the transformations. The goal was to make the transformation bold and crazy, but not creepy.

The group began by looking at various character transformations that have occurred on-screen, such as Mystique’s transformation in X-Men, which involved feathery, scaly textures. Yet, Pixar wanted something that was more exaggerated and stylized look-wise, as their character scales needed to be much bigger to fit into the style of this movie. The team also was inspired by the ripple that runs through Gigi the cat’s fur in Hayao Miyazaki’s film Kiki’s Delivery Service. 

The artists used its 3D pipeline to achieve the desired look, which includes tools that have evolved from previous shows, such as a silhouette sketching tool used on Inside Out. Also, there are new tools that were built for this film, such as robust controls to make the eyes more graphic, as well as the transformation rig used to shape-shift Luca and Alberto. 

During the transitioning phase, both the human and sea monster rigs are present, along with a third, the transformation rig. As parts of that rig are turned on, those elements from the two rigs (human and sea monster) are revealed. “It’s like a magic trick where we’re kind of just showing parts of the human and parts of the sea monster, but we give that control to the animators so they can slide things and turn things on and off, and show bits and pieces of each character,” says Skaria. “We literally have two Lucas in the same space and show parts of each.”

Typically such transformations would be hidden off-screen or would be obscured by adding smoke in front of the character, for instance, due to the effort involved. However, the director was very specific about this occurring on-camera in Luca. “It’s the core of the movie, it’s about Luca as a human emerging out of the sea monster, and we want the audience to see it,” says Skaria. 

When the character becomes fully human or fully sea monster, the transformation rig was not needed and the shot was animated normally. 



Transformation and Animation

The transformation occurs in and around 50 shots, so the artists spent a good deal of time and effort on it. Mostly, though, the characters appear in one form or the other. “We wanted to feel the hand of the artist in every-thing we did on this movie,” says Albright. For instance, all the sea monster scales were hand-painted by an artist. Those paintings then were used to derive the geometric scales the artists used as part of the transformation process. In total, the sea monster Luca has 3,436 scales on his body.

Luca’s animation style is inspired by 2D animation. “For animation, we wanted to incorporate the bold, illustrative choices and stylized timing of 2D animation, while preserving the richness we’ve come to expect from a Pixar film,” Venturini says.

In all, the film features 1,500 shots, but artists produced an average of 10 drawings per scene (amounting to about 15,000 drawings) to help the animators stay true to the illustrative design with their poses. 

According to Venturini, the facial rigs were especially different, particularly in the mouth area. The characters have fun, graphic mouth shapes that can be especially small or large. To get the consistent round corners of the mouth, though, required new rigging.

“To be more illustrative, we had to come up with new controls, particularly with this design language that Enrico wanted, and to be able to move the mouth all over the face and go into profile,” Venturini says, noting there are 221 and 223 individual controls in Luca’s and Alberto’s mouths, respectively, to help animators create the rounded mouth expressions used throughout the film. “Most of our characters in an average Pixar film have a narrower range of movement, so the rigging doesn’t have to be as robust or versatile. Immediately when we started to do some of our early animation tests, we were just breaking the technology that we had out of the gate. Then we started building the new pieces that we would need in keeping with the design language.”



Typically, the animators avoid having characters move into profile, but on Luca they embraced it, focusing a lot on the silhouette and design of the poses. Here, the silhouette is clean and round. There is not a lot of anatomy; the designs are simple, bold, and graphic. So they would not break the silhouette when the character is in profile, the artists would turn the head while keeping the mouth inside the silhouette and then popping it into the profile. Custom controls and sculpting let the artists adjust the silhouettes, profiles, and the shape of the mouth and the eyes to allow for the desired versatility. “It was more like a hand-drawn quality in 3D because we were literally sculpting in space with the camera,” adds Skaria.  

With the squash-and-stretch style came some fun design departures, including some multi-limb animation, popular in the 2D world, to illustrate fast action. This was done using a variation of the transformation rig, only in these instances it used two human rigs, for example, as opposed to a human and sea monster rig. 

Water Craft

With a film set in a seaside town and with a cast that includes sea creatures, you know there is CG water, and lots of it. Jon Reisch, effects supervisor, recalls looking at the storyboards two years ago and seeing “hundreds and hundreds of shots in Luca that involved water” — the sea in the background, the Portorosso harbor, the boys splashing in and out of the water, and more.

While Pixar’s tool set has become better and better at capturing realism when it comes to water, for this film, the focus was on stylization and playfulness, thus requiring the team to push their tools in a totally different direction in order to achieve more controllable and designable water. 

First, they focused on the color of the water, with all the beautiful blues and greens, driven through volumetrics underneath the surface. The goal was to make this water feel like it is from the Mediterranean as opposed to some tropical setting. “Volumetrics is one of the cornerstone building blocks we use in the effects department, typically for clouds, smoke, or explosions. But it turns out that the way light interacts with the water when it passes through the volume of the water in the Mediterranean Sea and in the ocean, it scatters and has similar properties to the way the light scatters around in a cloud,” explains Reisch. 



Second, the effects department pushed the stylization of the ocean surface and that of the splashes — and married those two worlds together. While Pixar has tackled water before, for this film the artists used a different system than they did on Finding Dory, requiring a good deal of back-and-forth work with the RenderMan team to figure out a way to seamlessly blend at render time the procedural stylized ocean that is mostly seen on-screen with the simulated areas of splashes by the characters.

Artists needed control over the sculptural shapes that would be injected into their splash simulations. To this end, Pixar reworked some of its tools, giving individual artist control over certain bands of frequency in the water sims by allowing them to dial the high-frequency detail up or down. “It was about challenging what our own preconceptions were about how we would approach that work and using the tools we had in a slightly new way to push into that more simplified, stylized, almost storybook look,” says Reisch.

Most of the effects work, including the cartoon water splashes, was done using SideFX’s Houdini, with the Houdini FLIP simulator at the core. The ocean, meanwhile, was shaded with RenderMan and OSL, then rendered in Foundry’s Katana. Custom nodes were used to generate the initial spectrum of ocean waves. 

Over the Land and Under the Sea

It’s clear that Luca, with its unique style, is somewhat atypical for Pixar. Then again, what really is “typical” for a studio that is constantly pushing new boundaries? 

A phrase we often hear in the film is “Silencio, Bruno,” a phrase turned by Alberto (and then by Luca) as a way of ignoring that little voice that tells you, “No, you can’t,” and holds you back. Thank goodness Casarosa and the Pixar team hushed that little voice when creating this very special film. Grazie.

Karen Moltenbrey is the chief editor of CGW.