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Chapter 1
Introduction to Computer
Graphics and 3D
This book will introduce
you to the workings of 3D animation
(called computer graphics, or CG) with one of the most popular programs on the mar-
ket, Autodesk Maya. It will introduce you to many of Maya’s features and capabilities
with the intent of energizing you to study further.
he best way to succeed at anything is to practice. Go through the exercises in this
book (more than once if you care to) and also think of exercises and projects that can
take you further in your learning process. A book, class, or video can take you only so
far; the rest is up to you. Imagination and exploration will serve you well.
his is not to say you can’t be a casual visitor to working in CG—far from it. Playing
around and seeing what you can create in this medium is just lat-out fun. Don’t lose
sight of that. If you feel the enjoyment slipping away, step away from the screen for a
while. Understanding your own learning pace is important.
hroughout this book, you’ll learn how to work with Maya tools and techniques at a
pace you set for yourself. his chapter will prepare you for the hands-on study that fol-
lows by introducing the most important CG concepts and the roles they will play in your
Maya work. When you’re learning how to work with Maya, the most important concept
is discovering how you work as an artist. If you have a basic understanding of the meth-
odology and terms of computer art and CG, you can skim or even skip this chapter and
jump right into working with Maya.
Topics in this chapter include:
■
Art?
■
Computer graphics
■
The stages of production
■
The CG production worklow
■
Core concepts
■
Basic ilm concepts
 2
■
CHAPTER 1: INTRODUCTION TO COMPUTER GRAPHICS AND 3D
Art?
Art, in many instances, requires transcendence of its medium; it speaks of its own
accord. Art goes beyond the mechanics of how you create it (whether by brush or mouse)
and takes on its own life. Learning to look beyond what you’re working
with
and seeing
what you’re working
for
is the key to creating art with CG. Try not to view this experience
as learning a sotware package but as learning a way of working to an end.
Relax and enjoy yourself.
It’s hard to relax when you’re trying to cram so much information into your brain. But
keep in mind that you should try not to make this experience about how a sotware pro-
gram works; instead, make it about how you work with the sotware. Maya is only your tool.
When hiring professional 3D artists, studios demand a strong artistic sense, whether
in a traditional portfolio or a CG reel. herefore, it’s paramount to fortify the artist
within yourself and practice traditional art such as life drawing, photography, painting,
or sculpture as you learn CG, beginning with the core principles introduced in this irst
chapter. Keep in mind that the computer you’ll be using for 3D work is nothing more
than a tool. You run it; it doesn’t run you.
So before you start learning a particular CG tool—Maya, in this case—make sure you
have a grasp of the fundamental issues underlying CG. It’s important that you do.
Computer Graphics
CG and CGI are the abbreviations for
computer graphics
and
computer graphics imagery
,
respectively, and are oten used interchangeably. CG literally refers to any picture or series
of pictures that is generated by an artist on a computer. However, the industry convention
is to use the terms
CG
and
CGI
to refer to 3D graphics and not to images created using 2D
image or paint programs such as Adobe Photoshop.
Most 2D graphics sotware is bitmap based, whereas all 3D sotware is vector based.
Bitmap-based sotware creates an image as a mosaic of pixels, illed in one at a time.
Vector-based sotware creates an image as a series of mathematical instructions from
one graphed point to another. his much more powerful method for creating graphics is
behind all the impressive CG images you’ve seen in movies, videogames, and so on. You’ll
learn more about vectors and bitmaps in the section “Computer Graphics Concepts” later
in this chapter.
If you’re familiar with 2D graphics sotware, such as Adobe Illustrator or Adobe
Flash, you already know something about vectors. Maya and other 3D graphics tools
add the calculation of depth. Instead of drawing objects on a lat plane, they’re deined
in three-dimensional space. his makes the artist’s job fairly cerebral and very diferent
 COMPUTER GRAPHICS
■
3
than it is for 2D art; in 3D art, there is more of a dialogue between the let and right
sides of the brain.
A Preview of the CG Process
he process of creating in CG requires that you either model or arrange prebuilt objects
in a scene, give them color and light, and render them through a virtual camera to
make an image. It’s a lot like directing a live-action production but without any actor
tantrums.
A large community on the Web provides free and for-pay models that you can use in your
scenes. Sites such as
www.turbosquid.com
and
www.archive3d.net
can cut out a lot of the
time you might spend creating all the models for a CG scene. Taking advantage of this gives
you the chance to skip at least some of the modeling process, if that isn’t your thing.
With CG, you work in 3D space—an open area in which you deine your objects, set
their colors and textures, and position lights as if you were setting up for a live photo shoot.
Ater you build your scene in 3D using models, lights, and a camera, the computer
ren-
ders
the scene, converting it to a 2D image. hrough setup and rendering, CGI is born—
and, with a little luck, a CG artist is also born.
Rendering
is the process of calculating lights and shadows, the placement of textures and
colors on models, the movement of animated objects, and so on to produce a sequence
of 2D pictures that efectively “shoot” your virtual scene. Instead of an envelope of 4n6
glossy prints, you get a sequence of 2D computer images (or a QuickTime or AVI [Audio
Video Interleave] movie ile) that sit on your hard drive waiting to be seen, and invariably
commented on, by your know-it-all friends.
In a nutshell, that is the CG process or worklow. his worklow is based on building,
arrangements, and relationships. But it’s an easy worklow to pick up and master in time.
It can be learned by anyone with the desire and the patience to give it a try.
Animation
Animation
shows
change over time
. In other words, animation is the simulation of an
object changing over a period of time, whether it’s that object’s position or size, or even
color or shape. In addition to working in the three dimensions of space, Maya animators
work with a fourth dimension: time.
All animation, from paper lipbooks to ilm to Maya, is based on the principle of
persistence of vision
that when we see a series of rapidly changing images, we perceive the
changing of the image to be in continuous motion. If you have a chance to pause and step
through an animated ilm, frame by frame, on your DVD player or DVR, you’ll see how
animation comes together, step by step.
 4
■
CHAPTER 1: INTRODUCTION TO COMPUTER GRAPHICS AND 3D
To create CG animation yourself, you have to create scene iles with objects that exhibit
some sort of change, whether through movement, color shit, growth, or other behav-
ior. But just as with lipbooks and ilm animation, the change you’re animating occurs
between static images, called
frames
, a term carried over from ilm. You deine the
object’s animation using a
timeline
measured in these single frames.
You’ll learn more in the section “Basic Animation Concepts” later in this chapter. For
now, let’s move on to the stages of CG production.
The Stages of Production
he CG animation industry inherited a worklow from the ilm industry that consists of
three broad stages: preproduction, production, and postproduction. In ilm,
preproduc-
tion
is the process in which the script and storyboards are written, costumes and sets are
designed and built, actors are cast and rehearse, the crew is hired, and the equipment is
rented and set up. In the
production
phase, scenes are taped or ilmed in the most eicient
order.
Postproduction
(oten simply called
post
) describes everything that happens ater-
ward: he scenes are edited into a story; a musical score, sound efects, and additional
dialogue are added; and visual efects may also be added. (In a ilm that has special efects
or animation, the actual CG creation is usually completed in postproduction. However, it
may start in the preproduction phases of the ilm or project.)
Although the work performed at each stage is radically diferent, this framework is
useful for understanding the process of creating CG as well.
Preproduction
Preproduction for a CG animation means gathering reference materials, motion tests,
layout drawings, model sketches, and such together to make the actual CG production
as straightforward as possible. Whether you’re working on a small job or a complex ilm,
entering into production without a good plan of attack will not only cause trouble but
also stunt the growth of your project. Not only that, but having diferent perspectives on a
subject based on research is the key to understanding it.
The Script
To tell a story, CG or not, you should put it in words. A story doesn’t need to contain
dialogue for it to beneit from a script. Even abstract animations beneit from a detailed
explanation of timings and colors laid out in a treatment (because there is likely no dia-
logue). he script or treatment serves as the initial blueprint for the animation.
The Storyboard
A storyboard is a further deinition of the script. Even a rudimentary storyboard with
stick igures on napkins is useful to a production. You break the script into sequences,
 THE STAGES OF PRODUCTION
■
5
and then you break those sequences into shots. Next, you sketch out each shot in a panel
of a storyboard. he panels are laid out in order according to the script to give a visual
and linear explanation of the story. Storyboards are useful for planning camera angles
(framing a shot), position of characters, lighting, mood, and so on. Figure 1.1 shows a
rough storyboard for a character falling asleep while watching TV.
Figure 1.1
A storyboard helps
deine the action.
The Conceptual Art
Conceptual artworks
are the design elements that you may need for the CG production.
Typically, characters are drawn into character sheets in three diferent neutral poses:
from the front, from the side, and from an angle called a
3/4 view
. You can also create
color art for the various sets, props, and characters to better visualize the colors, textures,
and lighting that will be needed. Props and sets are identiied from the script and boards
and then sketched out into model sheets. he better you visualize the conceptual art, the
easier it will be to model, texture, and light everything in CG.
Production
Production begins when you start creating models from the boards, model sheets, and
concept art. You model the characters, sets, and props, and then you assign textures
(colors and patterns). he animators take these
assets
and animate everything according
to the boards and script. Shots are then lit and ready for rendering. To make a long story
short, 3D scenes are created, lit, and animated in the production phase.
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