Chapter 7:

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Chapter 4:

IMD2214
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Chapter 4: Character Animation

Character Animation

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Lecturer:
Norhayati

Mohd

Amin

Introduction

IMD2214
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Chapter 4: Character Animation


Any object that is animated with expression and
tries to speak to the audience through its actions
is considered a character.


In fact, the same techniques used to animate a
dog might be used to animate a dancing bottle, a
tiger or a tree.

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3D Characters

IMD2214
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Chapter 4: Character Animation


A

3D character is a digital actor.


Whether your character is a tin can that bounces
with personality, or a photorealistic human
being, the animator will need to control it easily
and interactively.


The specific requirements of the character's
motion will dictate the complexity of the
character's controls.

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A Typical Character

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Chapter 4: Character Animation


The character’s mechanics must be convincing
to an audience and the skin and clothing must
also move and bend properly.


This process of preparing character controls is
called rigging and is used to let the animator
focus on the process of animating.


A fully rigged character can be quite complex
as it brings together skeleton joints, surfaces,
deformers, expressions, Set Driven Key,
constraints, IK, BlendShapes, etc.

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A Typical Character

IMD2214
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Chapter 4: Character Animation

Skeleton Joints

Character Controls

Constraints

Selection Handles

Deformers

Bound Surfaces

Kinematics

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Skeleton Joints

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Chapter 4: Character Animation


Joints are used to create a framework for a
character’s hierarchy.


The rotation of the skeleton joints defines the
motion of the character.


You can use inverse kinematics for even more
control.

BACK

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Character Controls

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Chapter 4: Character Animation


Using animation techniques such as Set Driven
Key and expressions, you can set up attributes
for controlling different parts of a character.


For example, a hand joint could have attributes
used to control the different finger joints.

BACK

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Constraints

IMD2214
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Chapter 4: Character Animation


It is possible to constrain the kinematic controls
of a skeleton to objects in your scene or even
simple locators.


You can then animate the constraint weights to
make a character pick something up or grab hold
of a fixed object.

BACK

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Selection Handles

IMD2214
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Chapter 4: Character Animation


Selection handles give you quick access to parts
of a character’s hierarchy that are to be
animated.


This makes it easier to work with a character
after it has been rigged up for animation.

BACK

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Kinematics

IMD2214
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Chapter 4: Character Animation


To control your skeleton joints, you can choose
from forward or inverse kinematics.


Forward kinematics
allows you to
set the

joint rotations
directly.


It is computation of the position and
orientation of robot's end
effector

as a function
of its joint angles.


It is widely used in robotics, computer games,
and animation.


BACK

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Kinematics (cont)

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Chapter 4: Character Animation


The reverse process is known as inverse kinematics.


Inverse kinematics

is the process of determining
the parameters of a jointed flexible object (a
kinematic chain) in order to achieve a desired pose


is a type of motion planning.


IK allows you
to position IK handles
, which rotates
the joints.


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Kinematics (cont)

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Chapter 4: Character Animation


forward kinematics is when you know the joint
angles and you find the coordinates


inverse kinematics is when you know the coordinates
and you find the joint angles.

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Bound Surfaces

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Chapter 4: Character Animation


Surfaces of a character’s skin and clothing can be
either parented or bound to the skeleton joints
to make them move together.


Binding places points from a surface into
clusters that are then associated with particular
joints.

BACK

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Deformers

IMD2214
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Chapter 4: Character Animation


To help the surfaces bend realistically at joints,
deformers such as flexors and influence objects
can be used.

BACK

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Chapter 4: Character Animation

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