Principles of Character Animation

1
Principles of Character Animation
2
Agenda

• Keyframes
• 2D vs 3D
• Weight and size
• The thinking character
• Moving holds
• Emotion
• Readability of actions
• A story trick
• Ask why

3
Learning Objectives

• Understand the principles of character animation.

4
Acknowledgments

• References
• Lasseter, John. Tricks to animating characters
  with a computer. ACM SIGGRAPH Computer Graphics,
  Volume 35 ,  Issue 2, May 2001 45-47.
• Available online.

5
What is Character Animation?

• Character animation refers to any time sequence
  of visual changes from the picture of a characer.
• The goal of character animation is to make
  characters that move in a convincing way to
  communicate personality and mood.
• It is OK to use tricks to obtain the desired
  result like in traditional animation.

6
Keyframes

• In classical animation
• Keyframes are poses of the entire character at
  important times in the scene.
• Generate the inbetweens afterwards.
• In computer animation
• Work in the hierarchy of a model.
• Create keyframes for the different controls of
  the model.

7
Keyframes

• In computer animation
• Work in the hierarchy of a model.
• Create keyframes for the different controls of
  the model articulation controls in the
  hierarchy.
• Number of keyframes needed varies between levels.
• Computer calculates the inbetweens based on a
  spline curve connecting the keyframe values.

8
Keyframes
9
Keyframes
10
2D versus 3D

• Classical animation is 2D versus computer
  animation is 3D.
• Create the animation viewing it at least from two
  views to see in 3D.
• From two different camera angles, the scene may
  look completely different.
• Can be used to generate crowds same character
  from different angles looks like different
  characters.

11
2D versus 3D
12
Weight and Size

• Traditional computer graphics techniques are good
  for making fixed objects look real.
• For moving objects, more is required to make them
  look real.
• Weight of objects influences the movement
• Heavy object moves more slowly, slower to
  accelerate, more difficult to stop. Allow time to
  start, stop, change movement direction.
• Light objects accelerate more easily, more prompt
  to move.

13
Weight and Size

• Movement of an object depends on
• Spacing between the poses themselves
• Behave like the object it models
• Timing of motion
• Giant moves more slowly, starts more slowing,
  stops more slowly
• Tiny character moves fast, starts fast and stops
  instantly.

14
The Thinking Character

• Every movement or action exists for a reason.
• Movements and actions are results of characters
  thought process.
• Give life to the character as the thinking
  character.
• Walt Disney In most instances, the driving
  forces behind the action is the mood, the
  personality, the attitude of the character or
  all three. Therefore, the mind is the pilot. We
  think of things before the body does them.

15
The Thinking Character

• Anticipation always lead the eyes or the head
  eyes move first, then head, then body. The eyes
  are the window to the characters thoughts. Can
  be a couple of frames.
• When an external force is driving the movement
  of the character, do not need anticipation by
  eyes movement.

16
Moving Holds

• Difference between hand-drawn animation and
  computer animation
• In hand-drawn animation, animate an action, then
  slow into a pose, and hold the drawing of that
  pose for several frames, before moving into
  action again.
• Not in computer animation, causes the motion to
  die. Use a moving old instead have some part to
  move slowly, like an arm, a head, or the whole
  body. Keep character alive with even a slight
  movement.
• Pitfall of motion capture can be applied from a
  human to a human, but not to a chicken. Modify
  the motion capture to adapt it to the character.

17
Emotion

• Personality of the character conveyed through
  emotion.EX character happy ? movements faster
  character sad ? movements slower
• Make characters different contrast of
  movement.Ex compare Luxo JR and Dad hitting the
  ball.

18
Readability of Actions

• Timing is important to making ideas readable
• Anticipation of an action
• Action itself
• Reaction to the action (follow through).
• Needs to be neither too slow, nor too fast.
• Action must not be too fast so that the audience
  cannot understand its meaning.
• Lead the eye of the audience to make action
  unmistakably clear.
• Timing, staging and anticipation.
• Must be done very clearly, as if the animator was
  saying Look at this, now look at this, and now
  look at this.
• Action should not be completely stopped before
  starting another action. Keep a slight overlap
  to maintain a flow of continuity.Ex Luxo Jr,
  action leads constantly (no sound)

19
A Story Trick

• In storytelling, timing of ideas and actions is
  important to lead the audience.
• Animation should stay slightly ahead of
  audiences understanding, or slightly behind.
• Action timed slightly ahead ? suspense and
  surprise
• Action timed slightly behind ? see the character
  discover what the audience already knows.
• Makes audiences emotions stronger.

20
Ask Why

• At every step of the production of an animation,
  ask yourself why?
• In the story, the design, the staging, the
  animation, the editing, the lighting, the sound.
• Character animation is when an object moves like
  it is alive, like it is thinking, like it is
  feeling, like it is moving following its thought
  processes.