(Editor’s Note: The following interview contains spoilers.)
One of the toughest tech challenges in Pixar’s “Elemental” was conveying what happens when fire and water — intense Ember (Leah Lewis) and sensitive Wade (Mamoudou Athie) — finally touch after falling in love. After all, fire and water don’t mix, and Ember resists temptation during the studio’s first rom-com because of danger. But she can’t take it anymore after spending a sublime moment together in an underwater garden. The result is a new chemical reaction that grows stronger and causes them to dance and eventually kiss.
“There was so much tension about what this contact was, fear that they might kill each other,” director Peter Sohn told IndieWire. “What is this chemistry? Is it magnetic, electric? This boiling, this cloudiness?
“Pete told me he was in Hawaii on vacation, and his kids were in the pool, and he got in,” visual effects supervisor Sanjay Bakshi told IndieWire. “And he had this idea in his mind of what would happen when they touch and visually like going into that macro view, where you see the fire flare up, you see the water get really active and then steam, and the sound effect is like a humming And he wanted it to be relatable, like the first time you touch someone you’re really interested in and you get that goosebumps.
Touch was uncharted territory for both the couple and Pixar. It represented the culmination of the animation studio’s first attempt to create fully simulated volumetric characters. Pixar studied the chemical reactions for fire and water in conjunction with macro photography (also referencing Darren Aronofsky’s “Requiem for a Dream”). “Visually, there’s a macroscopic view of injecting a needle, taking drugs, and what that chemical reaction is like,” Bakshi said. “We wanted to watch it go from that wider angle to a macroscopic view and then back again.”
After all that reference, though, the artists took artistic license to create the romantic chemistry. The flames react and float down Ember’s arm to his hand, while water bubbles flow from Wade’s arm to his hand.
“You feel like they’re doing something internal to protect themselves or prepare themselves,” Bakshi said. “So there’s a lot of specific effects work that shows how they’re preparing for that touch. And then, once they can touch each other, they interlace their fingers. Eventually, they almost enter into a hug, and as Ember leans into Wade, you see steam pouring out of the bubbles, going towards Wade’s shoulder area. It was all just a one off custom job.
But the whole conceit of these two elemental characters was an innovation that required a combination of realism and stylization (emphasizing energy over anatomy) with the help of new tools for rigging and performance. Ember’s flames worked like a gas stove and lit themselves. Wade was more complicated due to reflection and refraction and required special attention to control the water and not obscure his face.
Yet they couldn’t have made Ember without the help of an AI program called volumetric Neural Style Transfer (NST), which allowed them to sculpt the fire simulation into something more stylized. “So it’s going to take this raw fire simulation and organize the flames into these more illustrative shapes using target styles,” added Bakshi. “This is a technique we used on every fire character and every hit of Ember. There was no other option to be so illustrative and beautiful.
However, the sequence in the underwater garden perfectly sets the romantic mood for the touch. Wade takes Ember to the forbidden paradise with a protective bubble of water so he can see her favorite flower, the Vivisteria, up close for the first time. The opulent yellow and purple flower was designed by director Sohn (named in honor of his daughter Vivian) to look like origami that unfolds and was animated as a fabric simulation.
“When flowers are exposed to Ember light, they are able to unravel and bloom,” Bakshi said. “They look a little iridescent and have the hint of a beautiful particle trail. Then, as the screws pass over the water bubble, it looks like they are going through a car wash with a wiper effect. It’s been really challenging because they’re hitting the bubble and folding as they go, and the bubble is reacting to them.
“It was something, like so much of the film, that we just had words to describe what we wanted to happen,” he added. “No real graphics, but all in people’s imagination.”
