2. Outline
1. Principles of Traditional Animation
Applied to Computer Animation
(Lasseter, 1987)
2. Animation: Can it facilitate? (Tversky and
Morrison, 2002)
3. On Creating Animated Presentations
(Zongker and Salesin, 2003)
3. Principles of Animation
• Animation is possible because of a a biological
phenomenon known as persistence of vision
And The psychological phenomenon called phi .
• An object seen by the human eye remains chemically
mapped on the eye’s retina for a brief time after
viewing.
• Combined with the human mind’s need to
conceptually complete a perceived action.
• This makes it possible for a series of images that are
changed very slightly and very rapidly, one after the
other, seem like continuous motion .
4. What is Animation?
• 'To animate' literally means to give life to.
• Animating is moving something that cannot move on it's
own.
• Animation adds to graphics the dimensions of time, which
tremendously increase the potential of transmitting the
desired information.
• In order to animate something the animator has to be able
to specify directly or indirectly how the 'thing' has to move
through time and space.
6. Cel Animation
Made famous by Disney
24 frames per second therefore a minute
may require as many as 1,440 separate
frames.
Cel animation: is based on changes that occur
from one frame to the next.
Cel stands for celluloid which is a clear sheet
with images drawn on them.
The celluloid images are place on a
background that is usually stationary.
7. Path Animation
Moves an object along a predetermined path on the
screen
The path can be a straight line or have a number of
curves.
Starts with keyframes (the first and last frame of
an action).
The series of frames in between the keyframes are
drawn in a process called tweening.
Tweening requires calculating the number of frames
between keyframes and the path the action takes,
and then actually takes, and then sketches a
series of progressively different outlines.
8. Computer Animation
Typically employes the same logic and
procedural concepts as cell animation
You can usually set your own frame rate
At 15 frames a second the animation
may appear jerky and slow
2-D animation can be an acceptable
alternative to the expense of
creating video
9. 3-D Animation
3-D Animation involves three steps: modeling,
animation, and rendering
Modeling – the process of creating objects and
scenes
Animation – the process of defining the object’s
motion
Rendering – the final step in creating 3-D
animation.
Morphing is the process of blending two images into
a series of images
Warping allows you to distort a single image
Virtual reality (VR) creates an environment that
surrounds the user so that they become part of
10. Animation Techniques
• As is evident from the history, animators have used and
invented a variety of different animation techniques.
Traditionally most of the animation was done by hand.
• All the frames in an animation had to be drawn by hand.
Since each second of animation requires 24 frames (film),
the amount of work required to create even the shortest of
movies, can be tremendous.
11. Animation Techniques
• Key Frames
• In this technique a storyboard is laid out and then the artists draw the
major frames of the
• animation. These major frames are in which a lot of changes take
place. They are the key
• points of animation. Later a bunch of artists draw in the frames in
between.
• This technique is, of course, very time and effort intensive to animate.
12. Animation Techniques
• Rotascoping:
• Rotascoping is a technique where images are copied from
a moving video into an animation.
• The animator draws the motion and shape of the object by
referring to the video as opposed to imagining in his head.
• With the help of the rotascoping one can animate some
complex scenes that would be hard to visualize otherwise.
• The disadvantage is that one will have to hunt for the exact
video that one wants to animate.
13. Animation Techniques
• Motion Capture
• Another technique is Motion Capture, in which magnetic or vision-based
sensors record the actions of a human or animal object in three dimensions.
• A computer then uses these data to animate the object.
• This technology has enabled a number of famous athletes to supply the actions
for characters in sports video games.
• Motion capture is pretty popular with the animators mainly because some of
the commonplace human actions can be captured with relative ease.
• However, there can be serious discrepancies between the shapes or dimensions
of the subject and the graphical character and this may lead to problems of
exact execution.
14. Animation Techniques
• Simulation:
• Unlike key framing and motion picture,
simulation uses the laws of physics to
generate
• motion of figures and other objects. Virtual
humans are usually represented as a
collection of rigid body parts.
15. Overview: Traditional Animation
• Early 2D Animation: Used traditional
techniques
• Early 3D Animation: Neglected traditional
techniques.
16. 11 Fundamental principles of traditional
animation techniques
• Understanding the 11 Fundamental principles of
traditional animation techniques is essential to producing
good computer animation.
17. 1. Squash and Stretch
• Teaches basic
mechanics of
animation.
• Defines rigidity of
material.
• Important in facial
animation.
18. Squash and Stretch Cont.
• Can relieve the
disturbing effect of
strobing.
19. 2. Timing and Motion
• Gives meaning to movement.
• Proper timing is critical to making ideas
readable.
Examples:
1. Timing: tiny characters move quicker than
larger ones.
2. Motion: can define weights of objects.
21. 4. Staging
A clear presentation of an idea.
Some Techniques:
1. Use motion in a still scene or use of static movement
in a busy scene.
2. Use of silhouettes (to the side)
22. 5. Follow Through and
Overlapping Action
1. Follow Through
Termination part of an action.
2. Overlapping Action
Starting a second action before the first has completed.
Example: after throwing a ball
Example: Luxo Jr.’s hop with overlapping
action on chord.
23. 6. Straight Ahead Action and
Pose-to-Pose Action
1. Straight Ahead
Animator start from first drawing in the scene and
draw all subsequent frames until the end of scene.
2. Pose-to-Pose
Animator plans actions, draws a sequence of poses, in
between frames etc.
24. 7. Slow in and Out
Spacing of inbetween
frames to achieve
subtlety of timing and
movement.
1. 3d keyframe comp. Systems
uses spline interpolation to
control the path of an object.
2. Has tendency to overshoot at
extremes (small # of frames).
25. 8. Arcs
• Visual path of action for natural movement.
• Makes animation much smoother and less
stiff than a straight line.
26. 9. Exaggeration
• Making it noticeable the essence of an idea
via the design and the action.
• Needs to be used carefully.
Example: Luxo Jr. made
smaller to give idea of a
child.
27. 10. Secondary Action
• Action that results directly from another action.
• Used to increase the complexity and interest of a
scene.
Example:
Body movement is the primary
action, facial expression is the
secondary action
28. 11. Appeal
• Refers to what an audience would like to see.
• Character cannot be too simple (boring) or too
complex.
Examples:
Avoid mirror symmetry,
assymmetry is interesting.
33. Role of Personality
• Animator’s first goal is to entertain.
• Success of animation lies in the personality of the
characters.
Conclusion
Hardware/Software are simply not enough, these
principles are just as important tools too.
34. Critique
PROs
1. Clear and concepts
explained well with
pictures and
examples.
CONs
1. Need more examples on
“bad animation”
2. What really makes good
vs bad animation? Need
to make a better one on
one comparison.
3. Personality section: is it
necessary?
35. Outline
1. Principles of Traditional Animation
Applied to Computer Animation.
2. Animation: Can it facilitate?
3. On Creating Animated Presentations
36. Overview
• Graphics have many advantages.
• What makes graphics effective ?
1. Congruence Principle
2. Apprehension Principle
• Can Animation facilitate?
37. Advantage Graphics
1. Help in communication.
2. May save words by showing things that would otherwise
need many.
3. Externalize internal knowledge
I. Reduces the burden on memory and processing by off-
loading.
II. Makes underlying structures and processes transparent.
4. Used carefully can facilitate comprehension, learning,
memory, communication and inference
Graphics are not always effective. (text vs graphics)
38. Criteria 1:
Congruence Principle
The structure and content of the external
representation should correspond to the
desired structure and content of the internal
representation.
39. Animation
• By Congruence Principle: should be natural way for
conveying concepts of change, just as space in graphics is a
natural for conveying actual space.
• Appear to be effective for expressing processes ie. Weather
patterns, circuit diagrams, or circulatory systems etc.
• Compelling and attractive
40. Evaluating Animation
• Needs to be compared to graphics that do
not change with time, as it is change with
time that animation adds.
• How well does animation teach complex
systems: mechanical, biological, physical,
and operational.
42. Incomparable Content in Static and
Animated Graphics
Examples:
1. Circulatory system (Large et al., 1996) -
animated had blood pathways
2. Electronic Circuit (Park and Gittelman 1992) -
animated showed fine structure.
3. Pythagorean theorem (Thompson and Riding,
1990) - paper graphic equivalent to discrete
animation, but not equivalent to continuous
animation.
43. Incomparable Procedures In
Static and Animated Graphics.
1. Interactivity versus Animation
2. Prediction versus Animation
Why the confusion?
• Success of animation due to advantages of extra information
conveyed, rather than animation of the information.
• Animation is attractive and exciting.
44. Criteria 2:
Apprehension Principle
The structure and content of the external
representation should be readily and
accurately perceived and comprehended.
45. Why Do Animations Fail?
1. Animations may be hard to perceive.
2. Animations may be comprehended discretely.
3. Not universally preferred and often require
expertise for understanding.
46. Conclusions and Implications
1. Many apparent successes turn out not to
be successes.
2. Congruence and Apprehension Principles.
3. Interactivity may be key to overcome
animations’ drawbacks.
4. Animation must be used with care.
47. Crtitique
PROs
1. Good overview of
where animation
research is.
2. Clearly written.
3. Well supported
claims.
CONs
1. No figures!
2. Too many examples
were vaguely
explained.
48. Outline
1. Principles of Traditional Animation
Applied to Computer Animation.
2. Animation: Can it facilitate?
3. On Creating Animated Presentations
49. Overview
1. Microsoft estimates ~30 million ppt
presentations are made everyday
2. Animation could improve them.
3. PPT is essentially static in nature.
4. Examine how meaningful animations can be
created to improve live presentations.
50. Authoring Principles for
Animations for Presentations
1. Use parameterization at all levels of the
system.
2. Treat animations as models - animations
are treated as parameterized models that
have a single parameter: time.
3. Build slides hierarchically
51. Example of Parameterization
Parameterization lets us animate the diagram by manipulating a
single abstract “amount of pull” parameter, rather than managing
all the individual graphical elements individually.
52. 1. Implemented as a set of libraries in Python.
2. Users have access to complete, general-purpose
programming language.
3. A collection of drawing objects.
53. Three Major Drawing Objects
1. Parameterized diagrams - functions that draw
objects and are redrawn each time it is executed.
2. Animation Objects - One scalar parameter and
provides mapping to a set of other drawing
objects to be invoked.
3. Interactive Objects - same as animated objects
except can be edited while being played.
54. Animation Principles for
Presentations.
1. Make all movement meaningful
2. Avoid instantaneous changes
3. Reinforce structure with transitions
4. Create a large virtual canvas
5. Smoothly expand and compress detail
55. Animation Principles for
Presentations cont.
6. Manage complexity through overlays
• Do one thing at a time.
• Reinforce animation with narration.
• Distinguish dynamics from transitions.
56. Comparing to Presentation
Software
PowerPoint vs Slithy
1. WYSIWG (what you see is what you get)
2. Difficult to do complex animations :resort to
videos.
3. Built with animations in mind.
4. Script to describe animation.
CounterPoint vs Slithy
Focused on using animated navigation between slides
to convey the structure of the presentation.
57. Comparing to Animation
Software
1. Menv
2. Algorithm animation
3. Alice
4. Flash
Overall, SLITHY provides much more flexibility
and ease for animations for presentations.
58. Future Work and Conclusion
1. Still need to find an animated presentation
tool that is both very general and easy to
use.
2. Presented ideas provide useful steps at
creating and experiencing more
informative and exciting presentations.
59. Critique
PROs
1. Presents a somewhat novel
problem in today’s
presentations.
2. Interesting views on what
makes a good animation in
presentations.
3. Good implementation
details.
CONs
1. Presented Animation
Principles are not
supported.
2. Evaluation is based on
personal experience,
there is no user-case
studies.
3. Software requires an
expert level of a a user.
Editor's Notes
The papers summarized in this talk are the following 3. The first paper basically describes the basic 2D hand-drawn animation principles. The second paper is basically a review paper on animation research up to date and the last paper is on a software application called SLITHY that is used to create animated presentations.
Squash and stretch, timing/motion, anticipation, staging, follow through/overlapping action, straight ahead action/pose-to-pose action, slow in and out, arcs, exaggeration, secondary action, and appeal.
Drastic stretches = more pliable
Volume remains constant.
Tiny characters have less inertia and would move quicker than a large character.
Important that only one idea is seen by the audience at a time.
Too much leads to main idea being “upstaged” or overlooked.
Series of overlapping actions.
Used when scene requires more thought and poses and timing are important.
Early on, animation was drawing fairly even. But when poses of pose-to-pose animation became more expressive, animators wanted them to see them.
Obvious method but it.
Does not mean distorting shapes or objects or making an action more violent or unrealistic.
If one part exaggerated it runs the risk of standing out too much.
If everything is exaggerated it runs the risk of unrealism.
Such as two arms doing the exact same thing.
Preparation
Action proper
Termination of action.
Use of squash and stretch, anticipation, follow through, overlapping action, and secondary action.
Graphics should be accurately perceived and appropriately conceived.
Up to date: often too complex and too fast to be perceived accurately.
But animations seem to be effective in real time reorientations in time and space.
Two benefits:
Reduces the burden on memory and processing by off-loading.
Makes underlying structures and processes transparent.
Graphic should correspond to the content and format of the concepts to be conveyed. For example, maps, building plans and graphs and charts.
Newton’s Law of motion (Rieber 1990) - shows kick as it starts and stops the ball in
No equivalent procedures to assess benefits possible benefits from animation. Which facilitates learning.
Some kinds of motions, observers can select the correct path from an animation, but still produce it incorrectly.
If motion is conceived as in discrete steps, then it should be potrayed in discrete steps instead of being animated. IE. Operating a machine or assembling an object of some sort.
Already shown in previous talks that interactivity can facilitate learning but no studies on interactivity of animation vs interactivity of static graphics.
Animation in PPT is really embellishments to static layouts
Allows creation of a set of behaviors that restrict how parts of a diagram can move and change.
Both animations and models are objects that map a set of input parameters onto a set of output graphical primitives. Advantage: we can construct animations in smaller logical units and combine them to make slides.
Want the ability to nest models within each other to any degree of depth: Models and animations can be much more abstract in presentations, and often makes sense for them to be included in one another. Imagine a block diagram of a system, each block may contain a thumbnail animation to suggest to the audience the task performed inside the box. Small animations will also contain their own models as well.
Parameterization lets us animate the diagram by manipulating a single abstract “amount of pull” parameter, rather than managing all the individual graphical elements individually.
2. System also has a number of built-in objects to display things like background fills, text boxes, still images, and bulleted lists.
Squash and stretch and exaggeration : Found it distracting when the goal is to inform. That is people in the audience are more interested in the animation than the presenter himself.
Such as cross-fading - getting information on and off the screen. Sudden cuts create uncertainty and tension.
Using subtle transitions to increase impact of showy effects when they are used.
Use panning and zooming to increase area. Figure that slides off the same slide remains more “visible” than one that simply blinks out of existence.
Use the screen as a magnifying glass for examining figures of a variety of scales.
6. Separating detail into layers which become visible when required such as simple animated transitions such as quick fade-in or a small sliding motion can provide a suble and effective cue for differentiating the layers of information.
Slow with pauses so animations match the speakers words.
Presenter describes what is happening - talking about something different creates confusion.
Dynamics: refers to change over time in a real-world process
Transitions: animations used to highlight and draw attention and to move the talk from one topic to the next.
