AnimationCS 551 / 651

Lecture 3Lecture 3

Classical AnimationClassical Animation

Lecture 3Lecture 3

Classical AnimationClassical Animation

Review

KeyframingKeyframing

• Provides extensive user controlProvides extensive user control

• Automated but difficult to capture artist effectsAutomated but difficult to capture artist effects

– Liner, nonlinear, easing, squash/stretch, Liner, nonlinear, easing, squash/stretch, anticipation, follow-through, secondary motionanticipation, follow-through, secondary motion

KeyframingKeyframing

• Provides extensive user controlProvides extensive user control

• Automated but difficult to capture artist effectsAutomated but difficult to capture artist effects

– Liner, nonlinear, easing, squash/stretch, Liner, nonlinear, easing, squash/stretch, anticipation, follow-through, secondary motionanticipation, follow-through, secondary motion

Review

Motion CaptureMotion Capture

• Easy to capture style, but difficult to reuse/adaptEasy to capture style, but difficult to reuse/adapt

• Data cleanup / foot slidingData cleanup / foot sliding

Motion CaptureMotion Capture

• Easy to capture style, but difficult to reuse/adaptEasy to capture style, but difficult to reuse/adapt

• Data cleanup / foot slidingData cleanup / foot sliding

Review

ProceduralProcedural

• Build once, use oftenBuild once, use often

• Difficult to buildDifficult to build

ProceduralProcedural

• Build once, use oftenBuild once, use often

• Difficult to buildDifficult to build

www.sodaplay.com

http://taat.fi/taat/porrasturvat/

Euler Angle Interpolation

Euler Angle (Roll, Pitch, Yaw)Euler Angle (Roll, Pitch, Yaw)

• Frequently encoded as 3x3 matrixFrequently encoded as 3x3 matrix

• Simple interpolation fails:Simple interpolation fails:

Euler Angle (Roll, Pitch, Yaw)Euler Angle (Roll, Pitch, Yaw)

• Frequently encoded as 3x3 matrixFrequently encoded as 3x3 matrix

• Simple interpolation fails:Simple interpolation fails:

05.00

5.05.00

001

010

100

001

100

010

0015.0interp

Identity Rotate 90 degrees InterpolatedIdentity Rotate 90 degrees Interpolated about x axis (not orthonormal) about x axis (not orthonormal)

Identity Rotate 90 degrees InterpolatedIdentity Rotate 90 degrees Interpolated about x axis (not orthonormal) about x axis (not orthonormal)

Principles of Computer Animation

John Lasseter, "Principles of Traditional John Lasseter, "Principles of Traditional Animation Applied to 3D Computer Animation Applied to 3D Computer Animation", Animation", Computer GraphicsComputer Graphics, pp. 35-44, , pp. 35-44, 2121:4, July 1987 (SIGGRAPH 87).:4, July 1987 (SIGGRAPH 87).

Ollie Johnston and John Lasseter, Course 1 Ollie Johnston and John Lasseter, Course 1 at SIGGRAPH 94, "Animation Tricks".at SIGGRAPH 94, "Animation Tricks".

John Lasseter, "Principles of Traditional John Lasseter, "Principles of Traditional Animation Applied to 3D Computer Animation Applied to 3D Computer Animation", Animation", Computer GraphicsComputer Graphics, pp. 35-44, , pp. 35-44, 2121:4, July 1987 (SIGGRAPH 87).:4, July 1987 (SIGGRAPH 87).

Ollie Johnston and John Lasseter, Course 1 Ollie Johnston and John Lasseter, Course 1 at SIGGRAPH 94, "Animation Tricks".at SIGGRAPH 94, "Animation Tricks".

Comments from LasseterKeyframing

Computers are stupidComputers are stupid• Worst case, keyframe require for every frameWorst case, keyframe require for every frame

• John discovered that some degrees of freedom (DOFs) John discovered that some degrees of freedom (DOFs) require more keyframes than others to look naturalrequire more keyframes than others to look natural

• You must start with a clear idea of the motion you desireYou must start with a clear idea of the motion you desire

• Plan actions with thumbnail sketches and plot timing on Plan actions with thumbnail sketches and plot timing on exposure sheetexposure sheet

• Refer to sketches/timing frequentlyRefer to sketches/timing frequently

Computers are stupidComputers are stupid• Worst case, keyframe require for every frameWorst case, keyframe require for every frame

• John discovered that some degrees of freedom (DOFs) John discovered that some degrees of freedom (DOFs) require more keyframes than others to look naturalrequire more keyframes than others to look natural

• You must start with a clear idea of the motion you desireYou must start with a clear idea of the motion you desire

• Plan actions with thumbnail sketches and plot timing on Plan actions with thumbnail sketches and plot timing on exposure sheetexposure sheet

• Refer to sketches/timing frequentlyRefer to sketches/timing frequently

Lasseter: 2-D vs. 3-D

Native computer character is 3-DNative computer character is 3-D

• Sometimes makes it Sometimes makes it harderharder

– A character’s hand may go through its body A character’s hand may go through its body when seen from a certain anglewhen seen from a certain angle

• Sometimes makes it Sometimes makes it easiereasier

– Animation reuse: An animation may look very Animation reuse: An animation may look very different when seen from different locationsdifferent when seen from different locations

Native computer character is 3-DNative computer character is 3-D

• Sometimes makes it Sometimes makes it harderharder

– A character’s hand may go through its body A character’s hand may go through its body when seen from a certain anglewhen seen from a certain angle

• Sometimes makes it Sometimes makes it easiereasier

– Animation reuse: An animation may look very Animation reuse: An animation may look very different when seen from different locationsdifferent when seen from different locations

Lasseter: Weight and Size

• Rendering can make realistic-looking objects Rendering can make realistic-looking objects (marble, feathers, steel)(marble, feathers, steel)

• Good rendering benefits are lost if animation is poorGood rendering benefits are lost if animation is poor

• Physics matters – heavy things take longer to Physics matters – heavy things take longer to start/stop moving…start/stop moving…

• Proper timing/spacing of poses is more important Proper timing/spacing of poses is more important than the poses themselvesthan the poses themselves

• Rendering can make realistic-looking objects Rendering can make realistic-looking objects (marble, feathers, steel)(marble, feathers, steel)

• Good rendering benefits are lost if animation is poorGood rendering benefits are lost if animation is poor

• Physics matters – heavy things take longer to Physics matters – heavy things take longer to start/stop moving…start/stop moving…

• Proper timing/spacing of poses is more important Proper timing/spacing of poses is more important than the poses themselvesthan the poses themselves

Lasseter: Thinking Character

Every motion must exist for a reasonEvery motion must exist for a reason

• MoodMood

• PersonalityPersonality

• AttitudeAttitude

You must convey the character’s You must convey the character’s thoughts to tell the storythoughts to tell the story

• Use anticipationUse anticipation

Every motion must exist for a reasonEvery motion must exist for a reason

• MoodMood

• PersonalityPersonality

• AttitudeAttitude

You must convey the character’s You must convey the character’s thoughts to tell the storythoughts to tell the story

• Use anticipationUse anticipation

Lasseter: Anticipation

Lead with the Lead with the eyeseyes• Move eyes first, with lock-in of focus a few frames Move eyes first, with lock-in of focus a few frames

before the headbefore the head

• Head follows and leads the body by a few framesHead follows and leads the body by a few frames

• More delay implies more thought requiredMore delay implies more thought required

– Use this relationship as a toolUse this relationship as a tool

• External forces cause opposite timing relationshipExternal forces cause opposite timing relationship

Lead with the Lead with the eyeseyes• Move eyes first, with lock-in of focus a few frames Move eyes first, with lock-in of focus a few frames

before the headbefore the head

• Head follows and leads the body by a few framesHead follows and leads the body by a few frames

• More delay implies more thought requiredMore delay implies more thought required

– Use this relationship as a toolUse this relationship as a tool

• External forces cause opposite timing relationshipExternal forces cause opposite timing relationship

Lasseter: Moving Holds

Traditional 2-D animation permits “holds”Traditional 2-D animation permits “holds”• Reuse of one drawing for multiple framesReuse of one drawing for multiple frames

• This is one way to control timingThis is one way to control timing

In computer animation action dies In computer animation action dies immediatelyimmediately• Perhaps due to realistic rendering and smooth Perhaps due to realistic rendering and smooth

animationsanimations

Eye picks it up every timeEye picks it up every time

Traditional 2-D animation permits “holds”Traditional 2-D animation permits “holds”• Reuse of one drawing for multiple framesReuse of one drawing for multiple frames

• This is one way to control timingThis is one way to control timing

In computer animation action dies In computer animation action dies immediatelyimmediately• Perhaps due to realistic rendering and smooth Perhaps due to realistic rendering and smooth

animationsanimations

Eye picks it up every timeEye picks it up every time

Lasseter: Moving Holds

Have some part of the character continue to move Have some part of the character continue to move in same direction during holdsin same direction during holds

Remember to coordinate realism of character to Remember to coordinate realism of character to realism of motionsrealism of motions

• More realistic characters (rendering style and dimensions) More realistic characters (rendering style and dimensions) require more realistic movementsrequire more realistic movements

• This rule limits the straightforward reuse of human facial This rule limits the straightforward reuse of human facial mocap for non-human 3D charactersmocap for non-human 3D characters

Have some part of the character continue to move Have some part of the character continue to move in same direction during holdsin same direction during holds

Remember to coordinate realism of character to Remember to coordinate realism of character to realism of motionsrealism of motions

• More realistic characters (rendering style and dimensions) More realistic characters (rendering style and dimensions) require more realistic movementsrequire more realistic movements

• This rule limits the straightforward reuse of human facial This rule limits the straightforward reuse of human facial mocap for non-human 3D charactersmocap for non-human 3D characters

Lasseter: Emotion

Character’s personality conveyed through emotionCharacter’s personality conveyed through emotion

Emotion dictates animation paceEmotion dictates animation pace

Distinguish emotional state of two characters Distinguish emotional state of two characters through contrast in movementthrough contrast in movement

• No two characters perform same action in same mannerNo two characters perform same action in same manner

Character’s personality conveyed through emotionCharacter’s personality conveyed through emotion

Emotion dictates animation paceEmotion dictates animation pace

Distinguish emotional state of two characters Distinguish emotional state of two characters through contrast in movementthrough contrast in movement

• No two characters perform same action in same mannerNo two characters perform same action in same manner

Lasseter: Readability of ActionsTo make sure an idea or action is To make sure an idea or action is

unmistakably clear, the audience’s eye unmistakably clear, the audience’s eye must be led to the right place at the right must be led to the right place at the right timetime• TimingTiming

– Not too slow or audience eyes wanderNot too slow or audience eyes wander

– Not too fast or action is misunderstoodNot too fast or action is misunderstood

– The faster the motion, the more critical it is to The faster the motion, the more critical it is to make the audience focus on itmake the audience focus on it

To make sure an idea or action is To make sure an idea or action is unmistakably clear, the audience’s eye unmistakably clear, the audience’s eye must be led to the right place at the right must be led to the right place at the right timetime• TimingTiming

– Not too slow or audience eyes wanderNot too slow or audience eyes wander

– Not too fast or action is misunderstoodNot too fast or action is misunderstood

– The faster the motion, the more critical it is to The faster the motion, the more critical it is to make the audience focus on itmake the audience focus on it

Harold Whitaker and John Halas, Timing for Animation, 1981

Readability of Actions

Staging

• Audience can only see one idea at a time

• Object of interest must be contrasted against rest of scene

– Pick strongest and simplest technique

ex: Still object vs. busy background

Staging

• Audience can only see one idea at a time

• Object of interest must be contrasted against rest of scene

– Pick strongest and simplest technique

ex: Still object vs. busy background

Lasseter: Readability of Actions

Anticipation

• First action should not be brought to complete stop before starting second

–Slight overlapping preserves flow

–ex: Luxo Jr.

Anticipation

• First action should not be brought to complete stop before starting second

–Slight overlapping preserves flow

–ex: Luxo Jr.

Lasseter: Story Tricks

Animation must be timed to stay slightly Animation must be timed to stay slightly ahead or behind audience’s ahead or behind audience’s understandingunderstanding• AheadAhead conveys suspense and surprise conveys suspense and surprise

– Initial scene of Luxo Jr. where Dad is surprised Initial scene of Luxo Jr. where Dad is surprised by ballby ball

– Closing scene of Red’s DreamClosing scene of Red’s Dream

• BehindBehind reveals the story to the audience before a reveals the story to the audience before a character to convey character’s discoverycharacter to convey character’s discovery

Animation must be timed to stay slightly Animation must be timed to stay slightly ahead or behind audience’s ahead or behind audience’s understandingunderstanding• AheadAhead conveys suspense and surprise conveys suspense and surprise

– Initial scene of Luxo Jr. where Dad is surprised Initial scene of Luxo Jr. where Dad is surprised by ballby ball

– Closing scene of Red’s DreamClosing scene of Red’s Dream

• BehindBehind reveals the story to the audience before a reveals the story to the audience before a character to convey character’s discoverycharacter to convey character’s discovery

Lasseter: Ask Why

Why is this here?Why is this here?

Does it further the story?Does it further the story?

Does it support the whole?Does it support the whole?

• Change of shape shows a character is thinkingChange of shape shows a character is thinking

• ““It is the thinking that gives the illusion of life.It is the thinking that gives the illusion of life.It is the life that gives meaning to the expression”It is the life that gives meaning to the expression”11

• ““It’s not the eyes, but the glance – not the lips, but the smile”It’s not the eyes, but the glance – not the lips, but the smile”22

Why is this here?Why is this here?

Does it further the story?Does it further the story?

Does it support the whole?Does it support the whole?

• Change of shape shows a character is thinkingChange of shape shows a character is thinking

• ““It is the thinking that gives the illusion of life.It is the thinking that gives the illusion of life.It is the life that gives meaning to the expression”It is the life that gives meaning to the expression”11

• ““It’s not the eyes, but the glance – not the lips, but the smile”It’s not the eyes, but the glance – not the lips, but the smile”22

1. Frank Thomas and Ollie Johnston, Disney Animation – The Illusion of Life, 1981

2. Saint-Exupery, Wind, Sand, and Stars, 1932

Johnston Notes

Use attitudes and actions to illustrate ideas Use attitudes and actions to illustrate ideas and thoughts, not words and mechanical and thoughts, not words and mechanical movementsmovements

Squash and stretch the entire body for Squash and stretch the entire body for attitudesattitudes

• Preserve volumePreserve volume

• Useful for face tooUseful for face too

Use attitudes and actions to illustrate ideas Use attitudes and actions to illustrate ideas and thoughts, not words and mechanical and thoughts, not words and mechanical movementsmovements

Squash and stretch the entire body for Squash and stretch the entire body for attitudesattitudes

• Preserve volumePreserve volume

• Useful for face tooUseful for face too

Johnston Notes

• Change of expression and dialog are points of Change of expression and dialog are points of interest – don’t move head too muchinterest – don’t move head too much

• Concentrate on drawing clear, not cleanConcentrate on drawing clear, not clean

• Everything has a function – know whyEverything has a function – know why

• Let the body attitude echo the facialLet the body attitude echo the facial

• Find best part of character’s pose to squash Find best part of character’s pose to squash and stretchand stretch

• Change of expression and dialog are points of Change of expression and dialog are points of interest – don’t move head too muchinterest – don’t move head too much

• Concentrate on drawing clear, not cleanConcentrate on drawing clear, not clean

• Everything has a function – know whyEverything has a function – know why

• Let the body attitude echo the facialLet the body attitude echo the facial

• Find best part of character’s pose to squash Find best part of character’s pose to squash and stretchand stretch

Johnston Notes

The eye is pulled by the eyebrow musclesThe eye is pulled by the eyebrow muscles

Get a plastic quality in the faceGet a plastic quality in the face• Cheeks, mouth, and eyesCheeks, mouth, and eyes

The audience has a difficult time reading the The audience has a difficult time reading the first 6 – 8 framesfirst 6 – 8 frames

Actions can be eliminated and staging Actions can be eliminated and staging “cheated” if it simplifies the picture you are “cheated” if it simplifies the picture you are trying to show and it doesn’t disturb the trying to show and it doesn’t disturb the audienceaudience

The eye is pulled by the eyebrow musclesThe eye is pulled by the eyebrow muscles

Get a plastic quality in the faceGet a plastic quality in the face• Cheeks, mouth, and eyesCheeks, mouth, and eyes

The audience has a difficult time reading the The audience has a difficult time reading the first 6 – 8 framesfirst 6 – 8 frames

Actions can be eliminated and staging Actions can be eliminated and staging “cheated” if it simplifies the picture you are “cheated” if it simplifies the picture you are trying to show and it doesn’t disturb the trying to show and it doesn’t disturb the audienceaudience

Johnston Notes

Spend half your time planning your scene Spend half your time planning your scene and the other half animatingand the other half animating

How to animate a four-legged walk:How to animate a four-legged walk:

• Work out acting patterns with squash and stretch in Work out acting patterns with squash and stretch in body, neck, and headbody, neck, and head

• Animate the legsAnimate the legs

• Adjust up and down motion of body according to Adjust up and down motion of body according to legslegs

Spend half your time planning your scene Spend half your time planning your scene and the other half animatingand the other half animating

How to animate a four-legged walk:How to animate a four-legged walk:

• Work out acting patterns with squash and stretch in Work out acting patterns with squash and stretch in body, neck, and headbody, neck, and head

• Animate the legsAnimate the legs

• Adjust up and down motion of body according to Adjust up and down motion of body according to legslegs

Anticipation

Can be anatomicalCan be anatomical

• Swinging your foot back before kickingSwinging your foot back before kicking

Device that attracts viewer’s attentionDevice that attracts viewer’s attention

• Staring off camera until character enters at that Staring off camera until character enters at that positionposition

Can help convey mass. More wind-up or Can help convey mass. More wind-up or concentration implies increased scaleconcentration implies increased scale

Can be anatomicalCan be anatomical

• Swinging your foot back before kickingSwinging your foot back before kicking

Device that attracts viewer’s attentionDevice that attracts viewer’s attention

• Staring off camera until character enters at that Staring off camera until character enters at that positionposition

Can help convey mass. More wind-up or Can help convey mass. More wind-up or concentration implies increased scaleconcentration implies increased scale

Staging

Contrast is powerful staging techniqueContrast is powerful staging technique

• Motion is one exampleMotion is one example

• Original Disney characters were black and white (no Original Disney characters were black and white (no grayscale)grayscale)

– Important motions had to be drawn in silhouette Important motions had to be drawn in silhouette because limbs passing in front of others were not because limbs passing in front of others were not easy to seeeasy to see

– Even when grayscale (and color) is possible, Even when grayscale (and color) is possible, silhouette makes actions more visiblesilhouette makes actions more visible

Contrast is powerful staging techniqueContrast is powerful staging technique

• Motion is one exampleMotion is one example

• Original Disney characters were black and white (no Original Disney characters were black and white (no grayscale)grayscale)

– Important motions had to be drawn in silhouette Important motions had to be drawn in silhouette because limbs passing in front of others were not because limbs passing in front of others were not easy to seeeasy to see

– Even when grayscale (and color) is possible, Even when grayscale (and color) is possible, silhouette makes actions more visiblesilhouette makes actions more visible

Follow through and Overlapping Action

""It is not necessary for an animator to take a It is not necessary for an animator to take a character to one point, complete that action character to one point, complete that action completely, and then turn to the following action completely, and then turn to the following action as if he had never given it a thought until after as if he had never given it a thought until after completing the first action. When a character completing the first action. When a character knows what he is going to do he doesn't have to knows what he is going to do he doesn't have to stop before each individual action and think to stop before each individual action and think to do it. He has it planned in advance in his mind.do it. He has it planned in advance in his mind.""

""It is not necessary for an animator to take a It is not necessary for an animator to take a character to one point, complete that action character to one point, complete that action completely, and then turn to the following action completely, and then turn to the following action as if he had never given it a thought until after as if he had never given it a thought until after completing the first action. When a character completing the first action. When a character knows what he is going to do he doesn't have to knows what he is going to do he doesn't have to stop before each individual action and think to stop before each individual action and think to do it. He has it planned in advance in his mind.do it. He has it planned in advance in his mind.""

Walt Disney

Ease-in and Ease-out

A facsimile of physicsA facsimile of physics

• First, second, and third order continuityFirst, second, and third order continuity

• Remember challenges getting splines to interpolate Remember challenges getting splines to interpolate endpointsendpoints

A facsimile of physicsA facsimile of physics

• First, second, and third order continuityFirst, second, and third order continuity

• Remember challenges getting splines to interpolate Remember challenges getting splines to interpolate endpointsendpoints

Digital Editing

Frames are always represented digitally (no Frames are always represented digitally (no degeneration)degeneration)

Infinite compositingInfinite compositing

21Mb/sec required for playback21Mb/sec required for playback

1 hour of video = 76 Gb of storage1 hour of video = 76 Gb of storage

D1 and digital Betacam are industry D1 and digital Betacam are industry standardstandard

Digital to analog or film?Digital to analog or film?

Frames are always represented digitally (no Frames are always represented digitally (no degeneration)degeneration)

Infinite compositingInfinite compositing

21Mb/sec required for playback21Mb/sec required for playback

1 hour of video = 76 Gb of storage1 hour of video = 76 Gb of storage

D1 and digital Betacam are industry D1 and digital Betacam are industry standardstandard

Digital to analog or film?Digital to analog or film?

Homework

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