If you’re lucky enough to live in a town where the Cars 3 ‘Road to the Races‘ publicity tour stopped by for a visit, you might have gotten to see the exclusive clip from the upcoming film that has not yet been made available to the general public.
In the clip, Miss Fritter, the scary school bus in the photo above, races around after Lightning McQueen and Cruz Ramirez in a track that is full of dirt and looks like a race track destruction zone. As you might expect, the dirt turns to squishy, wet mud creating quite the visual that most movie-goers won’t necessarily give a second thought to. There were approximately 160 shots throughout the film that included mud! ‘Motherboard’ reports that “the [Pixar] visual effects team spent six months just experimenting with the mud – determining its nature and its physics.”
“The first part of the process was going out into the world, leaving our desks, and playing in the mud,” said Jon Reisch, effects supervisor on Cars 3. “What about this material did we need to get across? How would we simulate it and recreate its physics? How does it move? How does it break? How does it interact with the characters?”
Pixar has always done an amazing job forming its animation with a real-life source whenever there is one. Pixar’s effects team used a hands-on approach to researching mud for Cars 3. They traveled to parks in their hometowns and played with mud near water and they even made their own mud behind the Pixar studio using a garden hose! “Getting our hands in it and having that sort of physical connection is really important,” said Reisch. “You’re not portraying what you think it should be. You’re portraying what it really is.”
As another form of research, the team watched videos of tractor pulls along with destruction derbies to learn the way mud reacts to vehicles as they plow through it. Some members of the team even went to a monster truck rally to get a closer view of the mud slinging.
‘Motherboard’ reports that when Pixar first ran mud tests on Side FX’s Houdini software, they ran into some issues and really counted on their unique, hands-on research to help solve them. “The thing we kept finding,” said Reisch, “is that [our rendered] mud didn’t have variation in it. The mud looked like cake frosting or chocolate. And so we started to introduce the idea of varying the viscosity and adding layers to the mud puddles themselves.”
The team began to independently program various elements of the mud to react in varying ways. They even set up a water table “so that when a car ran through the mud, water would rush in and pool to fill the tire tracks. One section of the mud might be a bit more solid. Another section of the mud might be mostly water, mixed with a little dirt. They quickly realized that mud was a bit tricky to ensure the proper appearance on screen. “It’s one of those things that’s not really a liquid and not really a solid. It’s just somewhere between, all of the time” said Reisch.
There are two major elements to take into account with mud, and making it react like mud was only part of the challenge. The other part was to make it truly look like real mud. “Reisch credits the lighting and the set shading departments for making the material look wet, reflective, and glossy, and for directing the audience’s eyes to where they need to focus.”
Sometimes when the team focuses on making things look as true-to-life as possible, they have to step back from that realism, especially if it serves the film best. “Reisch recalls a shot where a car’s tires were kicking up massive waves of mud since the wheels were spinning at a simulated speed of 200 miles per hour. The team went in and changed the effect, so the car would create 60 miles per hour mud waves instead. It read better on-screen, and that’s an important factor in an action film like this one. The audience might only have a split second to visually interpret each shot.”
“On the whole, we’re always willing to break the physics if we need to serve the story,” said Reisch. “That’s really the main aim.”
Cars 3 skids into theatres June 16, 2017.
Content Source: Motherboard
Photo Source: Disney Pixar