Although Jack-Jack appeared in The Incredibles, director Brad Bird wanted a softer, fleshier baby for
“All the Parrs have basic geometric shapes,” says supervising animator Tony Fucile. “Bob is an upside-down U. Helen is a heart. Dash is a square. Violet is a circle. Jack-Jack is a circle with a hair horn. That’s easy to draw but hard to do in CG.”
For reference, the team looked at babies, including Fucile’s son Eli, who voices Jack-Jack. They looked for ways they could use new technology to change the original sculpt and create a softer character. For example, “We rounded and thickened Jack-Jack’s gums, made his eye-nose-mouth area tighter and sweeter,” Fucile says. “And he’s three months older, so we added a couple teeth.”
Audiences might not notice the difference, but they will notice Jack-Jack’s new superpowers: pyrokinesis, invisibility, laser vision, levitation, the ability to hang out on ceilings and walls, multiplication, phasing that gives him the ability to move through closed doors, projecting bolts of electricity, telekinesis, teleportation, transforming into heavy metal or goo, and turning into a demon baby.
“We used the opportunity to keep everything rooted in the original look, but bring it into modern technology,” says effects supervisor Bill Watral. “We can have so many more details. One of our biggest challenges with Jack-Jack was maintaining the look of the baby, whether he’s turning to goo or on fire. Nobody wants to see a burning baby.”
Effects technical artist Jason Johnston had the task of creating the fire effect.
“We went back to look at what was done in 2004, when Violet drops the baby into the bathtub, and we decided to redesign the look,” Johnston says. “Jack-Jack’s role would be bigger. He’d have more screen time. We’d need to read his animation. And, the technology can do more.”
The artists decided that Jack-Jack needed to be the source of the fire, not be on fire. There would be no smoke or embers because that conveys the idea that something is on fire, although anything he lights on fire could have them.
Then, they looked for sources of fire that burn but don’t look like they’re on fire, and vice versa. For the first test, they created fire with a transparent center, which looked interesting but didn’t feel right. They made the fire more orange and gave Jack-Jack glowing eyes. They tried changing the color of Jack-Jack’s skin, but he looked like a red devil baby. They allowed the flames to be more apparent. Then, they placed moving flames over Jack-Jack’s skin and gave him glowing eyes, which they liked. But, they continued experimenting.
“We added a new fire simulation over his body that we could affect without affecting the underlying simulation,” Johnston says.
Creating a final frame often involved 12 steps, starting with a base fire simulation, Jack-Jack renders, body-only fire simulations, Jack-Jack masks made with blurred renders, and various combinations and blends with glows and orange eyes.
“By having fire in different layers, we could control the effects per shot,” Johnston says.
To first put Jack-Jack on fire in front of Bird took the artists nearly a month. After that, Bird could have Jack-Jack on fire whenever he wanted.