Animation Vladimir Savchenko [email protected]

AnimationAnimationVladimir Savchenko

[email protected]

PrefacePrefacePrefacePreface

What is What is animationanimation?? AnimationAnimation is the rapid display of a is the rapid display of a

sequence of images of 2-D artwork or sequence of images of 2-D artwork or model positions in order to create an model positions in order to create an illusion of movement. It is an illusion of movement. It is an optical optical illusionillusion of of motionmotion due to the phenomenon due to the phenomenon of of persistence of visionpersistence of vision. .

• An An optical illusionoptical illusion - the information - the information gathered by the eye is processed by the gathered by the eye is processed by the brain to give, on the face of it, a brain to give, on the face of it, a perceptpercept that does not tally with a physical that does not tally with a physical measurement of the stimulus source. measurement of the stimulus source.

• MotionMotion means a continuous change in the position means a continuous change in the position of a body relative to a reference point, as of a body relative to a reference point, as measured by a particular measured by a particular observerobserver in a particular in a particular frame of referenceframe of reference. .


What is What is animationanimation??• According to the theory of According to the theory of persistence of persistence of

visionvision, the perceptual processes of the retina , the perceptual processes of the retina of the human eye retains an image for a brief of the human eye retains an image for a brief moment. Persistence of vision is said to moment. Persistence of vision is said to account for the illusion of motion which results account for the illusion of motion which results when a series of film images are displayed in when a series of film images are displayed in quick succession, rather than the perception of quick succession, rather than the perception of the individual frames in the series. the individual frames in the series.

• ObservationObservation is the observing of phenomena, is the observing of phenomena, actions, or eventsactions, or events

• In physics, observation refers to a provided set In physics, observation refers to a provided set of axes from which an observer can measure of axes from which an observer can measure the position and motion of all points in a the position and motion of all points in a system, as well as the orientation of objects in system, as well as the orientation of objects in it. it.


Animation techniques Animation techniques Traditional animation Traditional animation

- Also called - Also called cel animationcel animation, the frames of a traditio, the frames of a traditionally animated movie are hand-drawn. nally animated movie are hand-drawn.

• Walt Disney developed a number of principles• Computer graphics animators have adapted them t

o 3D


Animation techniques Animation techniques Computer animationComputer animation Computer animation encompasses a variety Computer animation encompasses a variety

of techniques, the unifying idea being that of techniques, the unifying idea being that the animation is created digitally on a the animation is created digitally on a computer.computer.


2D animation2D animation Figures are created and/or edited on the compuFigures are created and/or edited on the compu

ter using 2D ter using 2D bitmap graphicsbitmap graphics or created and edi or created and edited using 2D ted using 2D vector graphicsvector graphics. This includes auto. This includes automated computerized versions of traditional animmated computerized versions of traditional animation techniques such as of tweening, morphination techniques such as of tweening, morphing, onion skinning and interpolated rotoscoping. g, onion skinning and interpolated rotoscoping.

• TweeningTweening, short for in-betweening, is the proces, short for in-betweening, is the process of generating intermediate frames between tws of generating intermediate frames between two images to give the appearance that the first io images to give the appearance that the first image evolves smoothly into the second image. mage evolves smoothly into the second image.


2D animation2D animation

• MorphingMorphing is a special effect in animations is a special effect in animations that changes (or morphs) one image into that changes (or morphs) one image into another through a seamless transition. another through a seamless transition.

• Onion skinningOnion skinning is a 2D computer is a 2D computer graphics term for a technique used in graphics term for a technique used in creating animated cartoons and editing creating animated cartoons and editing movies to see several frames at once. movies to see several frames at once.

• InterpolationInterpolation is a method of constructing is a method of constructing new data points from a discrete set of new data points from a discrete set of known data points. known data points.


3D animation3D animation Figures are created in the computer Figures are created in the computer

using ,for example, polygons. To allow using ,for example, polygons. To allow these meshes to move they are given a these meshes to move they are given a digital armature (sculpture). This process digital armature (sculpture). This process is called rigging. Various other is called rigging. Various other techniques can be applied, such as techniques can be applied, such as mathematical functions (gravity), mathematical functions (gravity), simulated fur or hair, effects such as fire simulated fur or hair, effects such as fire and water and the use of motion capture and water and the use of motion capture to name but a few.to name but a few.

• The armature is analogous to the major The armature is analogous to the major skeleton and has essentially the same skeleton and has essentially the same purpose: to hold the body erect. purpose: to hold the body erect.


Animation principles1. Squash and stretch2. Staging3. Timing4. Anticipation5. Follow through6. Overlapping action7. Secondary action8. Straight-ahead vs. pose-to-pose vs. blocking9. Slow in, slow out10. Exaggeration11. Appeal


Animation principles

• Squash and stretchSquash: flatten an object or character by pressure or by its own power

Stretch: used to increase the sense of speed and emphasize the squash by contrast

Note: keep volume constant


Animation principlesStaging• Present the idea so it is unmistakably

clear• Audience can only see one thing at a time• Useful guide: stage actions in silhouette• In dialogue, character faces ¾ towards

the camera, not right at each other


Animation principlesTiming• Timing affects weight:– Light object move

quickly– Heavier objects move

more slowly• Timing can completely

change the meaning of an action


Animation principlesAnticipation• An action breaks down into:– Anticipation– Action– Reaction• Anatomical motivation: a muscle must extend before it

cancontract• Prepares audience for action so they know what to expect• Directs audience’s attention• Amount of anticipation can affect perception of speed andweight


Animation principleSecondary action• An action that

emphasizes the main point, but is secondary to it.


Animation principlesStraight-ahead vs. pose-to-pose vs. blocking • Straight ahead: proceed from frame to frame without

planning where you want to be in ten frames. Can be wild,

spontaneous. • Pose-to-pose: Define keyframes and “inbetweens”. • Blocking: computer graphics animators adaptation:

– Start key – framing at the top of the hierarchy– Refine level by level– Keyframes for different parts need not happen at the

same time.


Animation principlesSlow in, slow out• An extreme pose can be emphasized

by slowing down as you get to it (and as you leave it)


Animation principles

Exaggeration- Get to the heart of the

idea and emphasize it so the audience can see it.


Animation principlesAppeal • The character must interest the

viewer. • It doesn’t have to be cute and c

uddly. • Design, simplicity, behavior all a

ffect appeal. • Note: avoid perfect symmetries • Example: Luxo, Jr. is made to a

ppear childlike

Examples. Examples. Animation by space Animation by space

mapping technique mapping technique

Examples. Examples. Animation by space Animation by space

mapping technique mapping technique The space mapping technique is applied in 3D space and caThe space mapping technique is applied in 3D space and ca

n serve for computing of surface transformations according to n serve for computing of surface transformations according to the user demands the user demands

• The left image shows the “Lion-dog” model (courtesy of Yutaka OhtaThe left image shows the “Lion-dog” model (courtesy of Yutaka Ohtake and A Belyev of Max-Planck-Institut für Informatik) (24930 verticeke and A Belyev of Max-Planck-Institut für Informatik) (24930 vertices, 50000 polygons), whose surface was generated from range data s, 50000 polygons), whose surface was generated from range data

• The right image shows plausible deformations after applying space The right image shows plausible deformations after applying space deformations by two 3D points (the time required to calculate deformdeformations by two 3D points (the time required to calculate deformations is about 0.0001 seconds)ations is about 0.0001 seconds)

Examples. Examples. Facial AnimationFacial Animation

Examples. Examples. Facial AnimationFacial Animation

emotions1[1].aviemotions1[1].avi (7000 triangles, 100 frames (7000 triangles, 100 frames per sec)per sec)

elasticbox1[1].avielasticbox1[1].avi

Volume visualization and animationVolume visualization and animation

• Temporal transformation or metamorphosis can be Temporal transformation or metamorphosis can be useful in different applications, for instance, artistic useful in different applications, for instance, artistic animation or recognition tasks. animation or recognition tasks. arhnew.aviarhnew.avi

• Figures illustrate shapes constructed by the linear interpolation of tFigures illustrate shapes constructed by the linear interpolation of two (volume) shapes with using a linear blending function which specifwo (volume) shapes with using a linear blending function which specify the relative contribution of each shape on the resulting blended shay the relative contribution of each shape on the resulting blended sha

pe.pe.

Character animationCharacter animation

• NekoAnimation\Neko.htmlNekoAnimation\Neko.html

Character animationCharacter animation

• fontanim.movfontanim.mov

Key-frame animationKey-frame animation

• Artificial Artificial fishfish

• fish4.avifish4.avi

Particle physically based animationParticle physically based animation

• NekoAnimation\Cometaimage2.hNekoAnimation\Cometaimage2.htmltml

Documents

Animation Vladimir Savchenko [email protected]