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Pixar in a Box
Course: Pixar in a Box > Unit 15
Lesson 1: Rendering 101Introduction to rendering
Rendering is the final phase in film production, transforming 3D virtual space into a series of 2D images to create a movie. It's a complex, time-consuming process that involves calculating the color of each pixel by solving the "rendering equation". This equation describes how light, which determines color, bounces around in the environment.
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What programming language did I see being used? (It looked like C to me.)(1 vote)
It was probably C++ or something among the higher coding languages(3 votes)
wait, so those people at pixar do some of the parts from scratch??(2 votes)
how long does it take to movie?(1 vote)
i tried to make a rendered animation, and it took me 5 hours to make a 10 sec animation!
its exhausting. ;((2 votes)
Is rendering used in non-animated movies too? Just asking.(1 vote)
Yep. The company I work for, Muse VFX, does mostly live-action visual effects. We're a pretty small company, but even we have a render farm of about 30 computers (and getting bigger). We try to keep even our most complex images down to less than three hours per frame, but I've seen a couple of shots at that company that went up to 19 hours per frame.(2 votes)
If we can create the illusion of 3D on a 2D plane, can we create the illusion of 4D in a 3D area?(1 vote)
Is it hard to make a movie?(0 votes)
how long does it take to render something?(1 vote)
Depending on what you're rendering, it can take up to several years(1 vote)
- how long does it take to animate(1 vote)
- 10sec animation = 5hours(including making the animation and rendering)(1 vote)
- You must have some pretty smart five year olds in your area if that's the only prerequisite to understanding this!
I'm looking at that one repeated equation:
L(x, w_0) \int_\Omega f(x, w_i, w_0) L(x, w_i) cos(\theta) dw
Out of curiosity, does this equation have a name? What do the individual portions of the function calculate?(1 vote) - what is the difference from just scanning and displaying a series photographs?(1 vote)
Video transcript
Hello. Hold on for just a second, please.
Welcome to "Rendering." I'm Christophe Hery and
I'm a researcher at Pixar. Rendering is the last phase of
the pipline and film production that takes our movies
from this to this. Rendering is where the world we've created
in the virtual three-dimensional space of the computer is finally realized
as a series of perfectly rendered two-dimensional images
that play one after another for 96 minutes and
become our movie. Rendering is an incredibly
time-consuming process, all focused on answering
one simple question: "What color is this pixel –
and then this pixel – and then this pixel
and this pixel?" Seems simple enough. I mean, the balloon is blue,
so the pixel will be blue, right? Well not exactly. A pixel is a tiny portion
of the final image. It acts like a little window
into the virtual 3D world. To understand what
color it should be, we have to figure out
what part of the picture we see through that window. We translate this question,
"What color is this pixel?", into math. This equation is called
the "rendering equation." It's a mathematical description of how
light bounces around in the environment. I know we said "color."
And this equation is about light. But there's a good reason for that. Color is light – just light
+of different wavelengths. So when we ask the question,
"What color is this pixel?", we're really asking "What light is coming
through this pixel towards the camera?" The solution to the equation
will be the answer to our question. "This pixel is – purple?"
[Asks in an unsure way.] To render a movie like "Up,"
we have to ask this question: "What color is this pixel?"
billions and billions of times. But just like every part of this process,
each little calculation isn't hard to do. It's the layer upon layer
of calculation that makes it complex, but also makes it possible to bring
something this beautiful to the screen.