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Tradigital Blender
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Tradigital Blender
A CG Animator’s Guid e to Applying
the Classic Principles of Animation
Roland Hess
AMSTERDAM • BOSTON • HEIDELBERG • LONDON • NEW YORK • OXFORD
PARIS • SAN DIEGO • SAN FRANCISCO • SINGAPORE • SYDNEY • TOKYO
Focal Press is an imprint of Elsevier
Focal Press is an imprint of Elsevier
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This book and the individual contributions contained in it are protected under copyright by
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Notices
Knowledge and best practice in this field are constantly changing. As new research and
experience broaden our understanding, changes in research methods, professional practices,
or medical treatment may become necessary.
Practitioners and researchers must always rely on their own experience and knowledge in
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To the fullest extent of the law, neither the Publisher nor the authors, contributors, or
What We Won’t Be Doing 20
Review 21
Chapter 2: Your Tool Kit 23
Optimizing the Screen for Animation 23
Controlling the Sample Character 26
The F-Curve Editor 37
The Dope Sheet 52
Chapter 3: How to Not Waste Your Time . . . 61
Resources 61
Concept 62
Character Design 63
A Brief Interlude on the Subject of Composition 66
Contrast and Focus 66
Long Shots, Medium Shots, and Close-Ups 69
The Rule of Thirds 72
Framing 72
v
Object Location and Orientation 73
Storyboarding 74
Compiling a Story Reel 80
Aspect Ratios and Resolution or “Mommy, Why is that Man
so Skinny?” 89
Preparing a File for Animation 92
On Acting and Animation 92
Chapter 4: Basic Posing and Key Framing . 99
First Pose: Walking. . 100
Pose-to-Pose and Straight Ahead Animation 122
Continued Posing . . 123
Keeping a Static Shot Alive 130
Reviewing the Poses with an Eye to the Principles 137
Chapter 9: Straight Ahead Animation. . 247
Animating the Body 248
A Final Note On Pose-to-Pose and Straight Ahead Animation 263
Chapter 10: Animation Extras 265
IK/FK Switching 265
Picking Up and Dropping Items 269
The Setup 271
The Grab 272
The Drop 274
NLA 275
Repeating and Blending Actions 277
Examining Different Takes 282
Animating the Alarm 284
Conclusion 289
Appendix: Animation Playback and Rendering . . . 291
Index . 297
vii
Contents
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An Introduction to Character
Animation in Blender
Animation as both an art form and popular entertainment has existed for
almost a century now. The early attempts were received enthusiastically
more for their novelty than for the quality of their craft. That even holds
true today: animated movies often make it through the studio process not
because of their true entertainment value, but based on the novelty of the
technological innovation of the day. It turns out that the true core of
quality animation as both art and entertainment lies in the joining of two
elements: a compelling story and superior character animation.
Before we get too lofty though, let’s take a little test.
To the contrary, rotoscoping gives you a fairly dead result. It looks okay, but
there’s clearly something missing, even though every line and jot is taken
exactly from real life. The point is that, like with so many other art forms,
the goal of an animator is not to exactly duplicate the real world, but to
implement tools and techniques that give the illusion of reality when
observed. In fact, once you learn the techniques and rules of animation,
you can push the boundaries of reality quite a bit and get your viewer to
accept as believable things that simply aren’t possible.
Fortunately for all of us, the preceding generations of animators have
already cracked this particular code. Through research, hard work, and a lot
of trial and error, they determined a set of rules and tricks that when
followed can help to give your own animations the feeling of life. Not all
animators (or books, for that matter) agree on exactly what these rules are,
or exactly how much emphasis you should put on one over the other.
However, there is an acknowledged “core” set of rules that are generally
used when teaching, and these are referred to as the “Twelve Principles of
Animation.”
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The Twelve Principles
Throughout the rest of the book, we’ll be animating a single shot using
these principles. As we do that, you’ll see exactly where and how they fit
into the animation work flow. For now though, let’s get an overview of the
principles themselves. In order to demonstrate them, we need a model. The
animation puppet that’s included with this book will do. Say hi to “Junot”
(Fig. 1.1). The character has four different skins, two female and two male,
one each with a full skin (like in the figure) and another made of separate
parts. You can see “Meyer” (the guy) in “tin can” mode in the other half of
Fig. 1.1. Looking good, Meyer. Looking really good.
Squash and Stretch
In Fig. 1.4, Meyer is about to throw a devastating punch. What’s that you say?
He isn’t? Clearly, Meyer does not look like someone who is about to strike.
Myths about Bruce Lee being able to deliver a devastating blow from mere
inches away without any kind of wind up aside, when one person—and thus,
FIG 1.2 Junot Stretching as She
Flies.
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FIG 1.3 (a, b) Smith Just Fell Off
the Roof. Don’ t Worry. He’s Okay.
FIG 1.4 AreYouGonnaDo
Something, or Just Stand There and
Bleed?
An Introduction to Character Animation in Blender
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acharacter—does something, one almost always anticipates the action.
The larger or more forceful the final action, the correspondingly big the
anticipation must be to make it feel right.
Anticipation helps to bring balance to your animation, not in the sense of left-
to-right or in making sure that the character’s weight makes sense over its
points of support, but balance in time. What comes after necessitates that
something comes before.Wedon’t think about it in those terms when we go
about our daily lives, but that is only because our bodies are so good about
planning ahead for us. Almost constantly, our bodies are one step ahead of us,
preparing themselves for the next thing that they already know we are going
to do. What happens when our bodies don’t plan properly and that
anticipation doesn’t happen? We turn around and walk into the door (or flying
ball, or car) we didn’t see and a whole different branch of physics takes over.
Additionally, anticipation can be used to grab and direct the viewer’s
attention. Not only does it provide the proper physics, but it also shouts
supposed to be and the visual lines of the light and the ground itself
point us to Junot.
FIG 1.6 Citizen Kane This Is Not.
Composition Matters.
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Not every shot must be a stylistic masterpiece, but you at least need to
make sure that your staging isn’t fighting against your animation. Your
animation will lose.
Overlap and Follow Through
Although they are used for different effects, both of these terms
demonstrate the physical principle of inertia on the character. Remember
Newton’s first law of motion (paraphrased): stuff wants to remain at its
current velocity (which could include zero velocity—standing still), unless
something happens to it. Kind of obvious, but the implications in animation
are immense. Inertia is simply an object’s desire to just keep doing what it
is that it was doing before. A block of wood on the ground isn’t going
anywhere by itself. Give it a kick, and it takes off.
Think about the foot that gave the kick for a moment. It was just happily
planted on the ground a moment ago, when all of the sudden the hip
rotated, which pulled the upper leg along with it, which put torque on the
knee joint, which transferred that energy to the lower leg, on again to the
foot which finally moved. In real time, it didn’t take long for that chain of
motion to reach the leg, only a fraction of a second, really. But each part of
the leg experienced inertia and wanted to just stay where it was until
something else made it move. If you were to slow down a karate kick with
high speed film, the effect would be obvious. At first, the foot and lower
leg drag behind the rotating hips and driving quads, only snapping forward
at the end like a whip.
Fig. 1.8 shows Junot’s leg doing just this. When you make your characters
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beginners think that since the computer handles this for you, it’s not
relevant any more.
While it’s true that computer interpolation can generally handle ease in and
out, the way that it does so encodes a lot of information for the viewer.
Check the very standard “bouncing ball” diagram above in Figs. 1.9 and 1.10.
The Fig. 1.9 demonstrates a standard ease in/out for a moving ball. Note
how the more widely spaced balls near the bottom of the figure suggest that
the ball is moving rapidly there, while the closely spaced ones near the top
of the arc indicate slower vertical motion. It looks like a ball bouncing along
afloor.Incontrast,Fig. 1.10 shows a different motion path, one without a
“bounce” point where our intuition tells us that a floor would belong in the
other illustration. It certainly doesn’t look right for a bouncing ball. Perhaps it’s
an overhead view of a ball weaving back and forth across a plane. Really
though, the only difference between the two motion paths of the ball is the
way that slow in/out has been handled. Properly handling this slow in/out is
crucial to the perception that your motion is physically correct.
Arcs
This one’s pretty simple, and not as much of a problem in 3D as it is in
traditional animation. Fig. 1.11 shows Smith’s arm m oving at t he
shoulder. Note the arc that the fingertips make. It’s pretty obvious why this
FIG 1.9 Two Balls, Moved in Time
(Ball Bouncing along a Floor).
FIG 1.10 Two Balls, Moved in Time
(Ball without a Bounce Point).
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happens. Your arm is more or less a rigid figure. If you brace the elbow,
your arm will be the same length no matter how you position your
shoulder. In traditional animation, artists called “ In Betweeners” had the job
Secondary action can give dimension to your characters. Is the secondary
action at odds with the primary action in a meaningful (but subtle) way?
Perhaps the character is conflicted. A purposeful, determined character’s
secondary actions will appear directly in service of the primary. Secondary
action can also help to provide balance to your character, both physically
and visually. A strong primary action will need to be balanced in time by
anticipation and follow through, but an extreme action like reaching way
up to grab something from a shelf should be balanced with a secondary
action, integrated right into the pose. The rear leg lifting off the ground
provides this, as shown in Fig. 1.14.
Timing
While arcs a nd secondary action are fairly easy concepts to learn, timing
is probably the most difficult. There are so many aspects to timing that
you could devote your entire life to studying it and probably not learn
everything that there is to learn. Su mmed up simply, timing is “When
thi ngs happen.” It can convey an enormous amount of information.
Fig. 1.15 shows a ball colliding with a box. The timing of what happens
next tells the viewer a lot about the reality of the scene. If the ball stops
dead, and the box slowly tips over until it falls off the ledge, the timing has
indicated to us the relative masses of the two objects. If both the box and
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ball fly off the ledge, with the ball hardly slowing down, it tells us that the
ball was heavy and that the box was probably empty.
Timing can refer to such overall issues as when one character enters a scene
relative to something important that just happened. It can be as tiny as how
long it takes a particular character to blink. Consider one more timing
example: a character hits another one with a cast iron skillet. If it is done in a
serious fashion, the timing of the action would need to be realistic, and the
result would be violent. Change the timing though, and the whole timbre of
desire to recreate the real world in such exacting detail.
We don’t need to. We can use the shorthand.
Part of that abbreviated visual language lies in exaggeration. Take a look at
the video called “Junot Strut” on the web site (Fig. 1.16). If a real person
walked like that it would be ridiculous, but when you strip away all of the
subtleties of the real world, it works. In fact, it only works because of the
exaggeration.
Exaggeration is not only about making things bigger and more intense,
although that’s the simplest form of it. It is really about emphasis: what
traits within our characters we choose to highlight as animators.
Solid Drawing
In traditional animation, this refers to the ability to draw. You have to be
good at it. Really good, actually. If you’re not, you’re not going to make it.
In CG, one can (in theory) be a very good animator without being able to
draw even a bit. The goals of “solid drawing” in traditional animation are to
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have your characters and sets drawn in a professional fashion and to have
elements drawn identically from frame to frame. A face has got to look like
a face, and if you can’t draw one, well, forget it. Likewise, if you’re
animating a character turning around and you can’t make sixty drawings of
your character in a row that make it appear to hold its volume as it rotates
in space…
Fortunately, the computer takes care of that aspect of “drawing” for us. Yes,
you need construction skills when you design and model your own
characters and sets, but once it’s time to animate, you don’t need to worry
about it so much any more.
Solid drawing is not lost on us though. It comes through in our other
decisions: how we pose the character, the camera angle, and how we use
our tools. “Solid drawing” is a measure of how well a traditional animator
the odds are that at some point, you’ll want other people to see your work.
Making something that has to appeal to millions to have any chance of
distribution is old and busted. Making something that appeals to yourself
and letting the Internet help an audience to find it is the new hotness.
Straight Ahead Action and Pose to Pose
This last principle has no fancy illustrations, as it refers more to a method
of working than anything else. When an animator decides that they want
to use the “straight ahead” method, they think: Smith is being chased by a
tiger. I want him to careen through the jungle, flailing madly and tripping
over himself and everything else around him in panic. Then, they proceed to
do just that, from start to finish, literally. On the first frame, they create
Smith’s first pose. Advancing a few frames, they create the next pose.
Repeat. Now, a classical (i.e., hand drawn) animator might animate Smith’s
body and legs in a straight ahead fashion, then go back and fill in the
arms, then, hair and any flowing clothes. But each time, the animator thinks
about all of the other principles and builds them into each pose as he
works. There is no “Well here’s a key pose, and I’ll just go back later and
add the overlap and anticipation.” It’s straight ahead.
The result of well-done straight ahead animation is usually dynamic, full of
energy, and often just on the verge of losing control. Happy accidents can
occur while working that bring out aspects of the action you never would
have considered from an analytical standpoint. The down side is that it
sometimes doesn’t fit too well with production schedules and plans (“It
took him how many frames to get to the other side of the room?!”). It can
also end up feeling too loose. To make it work, you have to really know
what you’re doing.
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