where toys can come alive, or fish can talk or monsters can roam the world.

While it's common knowledge that Pixar's movies are the

product of computer animation, you might be surprised by

the amount of technology that was necessary to make them

possible. In fact, Pixar is largely responsible for some of

the most significant developments in computer graphics

history. A lot of people look at the product and they say,

oh it's the artwork and so they focus on that. But they

don't understand what went behind it. It's a blend of the

technology and the art that really makes it work. Behind

every one of Pixar's films and the visual effects of many

iconic movies to come out in the past 30 years, is a piece

of software called RenderMan.

RenderMan is a renderer, the final tool at the end of a

production pipeline that compiles all the 3D assets created

for a film. It's what translates the virtual camera the

artists work with during an animated or visual effects

production into the final image that we see of the movie.

There's lots of tools that companies and Pixar write to do

the 3D modeling, the animation, motion, camera definitions,

all flow into the very end of this software pipeline and that's the renderer.

Pixar got its start during computer graphics' infant stages.

When the most advanced CG images were primitive polygon

shapes. At this time, animation was strictly done through

illustration. It was an artist's medium, with every frame

drawn by hand and photographed into a film reel. But in the

late 70s, that began to change. In 1979 after the success

of Star Wars, George Lucas wanted to bring high technology

into the film industry and he was the only person in the

film industry who thought this was a good thing to be spending money on.

Ed Catmull was part of a small group of people in the

industry who recognized the potential of computer graphics

to create animated films. He joined LucasFilm to head its

computer division and set to work solving some of the

challenges in CGI, such as motion blur. The engineers had

to start square one, developing all the software and tools

needed to create characters and animations, everything

that's commonplace today. During this process, they

developed the precursor to RenderMan called REYES, which

stood for "Renders Everything You Ever Saw."

They built this renderer and that's what we used on the

early films like Star Trek II: The Wrath of Khan. We used

it on Sherlock Holmes. We used it on our early short films, Luxor Jr.

Lucas' group eventually spun off as an independent company

purchased by Steve Jobs, which marked the beginning of

Pixar. They would continue to go on making animated shorts,

creating the iconic Luxo lamp characters and receiving the

first Academy Award for a computer generated short. With

each and every project, they slowly evolved their tools and

the REYES renderer, eventually creating RenderMan, which

would go on to have a monumental impact in animation and

visual effects. As part of the sale to Steve Jobs, Lucas

had the rights to use Pixar's technology for their VFX

projects. Using it to create the groundbreaking CGI scenes

for the genesis sequence in Star Trek II: The Wrath of

Khan, the pseudopod creature in The Abyss, the T-1000 in

Terminator 2: Judgment Day and the dinosaurs of Jurassic Park.

When Jurassic Park came out in '93 it changed everything.

Within about a two year period, this industry which had

been very digital averse threw the switch on everything,

digital audio, digital video and computer graphics.

People thought of us like this overnight phenomenon, but in

fact, we'd been working on it for 20 years. And then Toy

Story came out two years later which changed animation history.

We always knew from day one, we wanted to do a feature. We

wanted to get into that arena. We did all the short films

because that was our stepping stone towards that. So when

we finally got Toy Story out there that was sort of like,

agh we did it. And then you go, well what's next?

Toy Story was a knockout success and launched the once

struggling company into a future filled with box office hits.

Pixar focused its efforts full-time on making more animated

feature length films. And with that came a slew of demands

to push its animation technology to new heights.

Every film represents both the directors and the artists

wanting to push in some new technical direction. And so the

rendering technology, and indeed all the tools, are sort of

structured in a way that they can be remade and remade and

remade over time to meet the artistic requirements that the

directors and artists bring to the table. New and more

elaborate ways of specifying crowds or foliage or fur on

animals. That stuff is constantly changing.

RenderMan is basically our artist's tool to create the

images that we want. Every new thing they come up with it

makes all these different images and worlds possible. It's

just sort of making the paintbrush better and better. A

film like Monsters Inc. its like, OK, we want the main

monster to have hair on him. Sullivan should have hair on

him, and everyone's like, yeah, we don't know how to do

hair. OK, so we're gonna have to R&D a project to figure

out how to do hair. And then the next one is Finding Nemo

and it's underwater. How do we do underwater? OK, let's

figure out underwater. There's these huge hurdles that

you're getting over because none of those movies were

possible in the beginning and there's this big R&D project to figure it out.

Making an animated film is an extremely time and labor

intensive process that draws upon the talents of hundreds

of artists and computer engineers. It's on the order of

20,000 person weeks. We shoot for lower than that but we've

had much worse actually. Once the story is figured out for

a film, which can take months, even years itself. Artists

start by creating all the different digital assets needed.

Every character, prop and location must be sculpted and

modeled. From there, the surfacing team adds all the

relevant textures. Objects that are wood or metal are given

the appropriate materials to reflect their composition.

Clothing is given a fabric appearance, skin an organic look

and so on. Character models have controls attached to their

limbs so they move in a realistic way. Once all of these

assets are complete, animators bring the characters and

world to life, conveying the story through personality and

action. Completed shots are then passed on to the lighting

department, which gives the film its cinematic look and

style.

This is before lighting and you kind of get a sense of what

the world looks like a little bit. But then we throw the

lighting in there and all of a sudden you can see WALL-E,

where before you can't even really see WALL-E, but you

start to pull WALL-E out.

Someone like me, the lighting DP might go on three years

before it ever comes out in theaters and we create a whole

three-dimensional world inside the computer. And if we

don't put lights in it it actually comes out black because

the computer is trying to mimic real life. And that we have

little icons of lights we move around. So if it's sunset, I

put the sun in and I can make it kind of orange and put it

at the horizon and start sort of building the scene up that way.

The Coco set at Pixar was I think one of the most

complicated that we've ever put into a film. And it was

difficult because the cameras that they chose to fly

through the world of the dead, or through the giant main

Grand Central train station, or the big cemetery, each of

those sets were hugely complex. One scene in Coco there was

eight million light sources illuminating in this sort of

interesting glow of candlelight and other light sources. If

you have more than a dozen lights it's often a problem and

so to scale that up into thousands and millions was a huge challenge for RenderMan.

This is the shot where we have eight and a half million

lights and it's like, I don't know, that's probably eight

million more lights than we've ever done in a scene before.

Because the assets being worked with are extremely resource

intensive from a computing perspective, artists must work

with lower resolution versions of the film. The actual

final image and look isn't known until it's processed

through RenderMan. Taking all the lighting, shading and

data aggregate into an image and turning it into a finished

2D frame. Compiling all these digital assets and processing

them into their final form is an extremely intensive computing task.

A typical frame takes hours to render, if you were going to

render them all on your home computer it would take a

couple hundred years probably to make one of these movies.

And so we solve that problem by having whole networks full

of computers that all render simultaneously different

frames at the same time. The sequences being rendered by

Pixar are so complex, even with state-of-the-art machinery,

it can take days. An image is anywhere between 50 hours to

100 hours, on modern computers.

That roughly translates to around 1,200 to 2,4000 hours of

rendering for every second of a movie.

I always try and remind people that we're not pushing a

button and a movie comes out the back end. That the huge

number of people involved, from fine artists through the

engineers that are writing RenderMan. It's a very human

intensive task making one of these films.

The influence of Pixar's work in computer animation had a

profound impact on the industry, but its applications

spread far beyond just entertainment. From the beginning,

when we started building the renderer we were thinking

about commercializing it. Making it available to anybody

who wants to use it in doing visual effects, to doing

animation, to doing scientific exploration. If they want to

make images, it's basically a way of making images.

There's a big advertising market. People use it in

architecture visualization. One of our longest standing

customers is NASA. There's a group there that is tasked

with visualizing some of the huge amounts of data they get back from their satellites.

Over 30 years ago, Pixar started as a hyper technical

software company pioneering advances in computer graphics and animation.

We're able to tell the story we want to because the

technology enables us to. Ultimately what we're doing here

is really this amazing combination of art and technology

that, if you pull them apart, they aren't as strong as when

we combine them here. In the early days, we sort of had to

hold it back. I had to tell John Lasseter, No, I just can't

let you try to make it rain in this sequence. We can't get

it done in time. We don't want to make those restrictions

anymore, we want to try to make it be whatever you want. It

shouldn't be the renderer that's holding us back.