The technology allows us to build fanciful kinds of worlds
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.
