The second day of three found James diving into the techniques and mechanics of effective animation.  He worked his way through a variety of topics pointing out key concepts and approaches that he has discovered throughout his animation career.

Believability.  Making acting choices believable enough so the audience forgets that the characters are animated.  You need to have a good command over how the world works so that the audience will buy into your character’s movements.  You want them to forget that the characters are animated.

Body Acting

Muppets are James’ favorite example of acting with just the body.  Without any facial expression they’re able to communicate the attitude.

In order of importance to James in animating a scene:

• 1. Body Language
• 2. Expression
• 3. Lip Sync

The body is the heaviest part of a character and therefore takes longer to change direction (see Inertia below).  To try this out with your own body, move your head left to right 6 inches.  Takes a relatively short time.  Now try moving the same distance with your torso.  Takes longer.

It’s not that heavier things move slower, just that it takes them longer to get up to speed.  That’s what will make it look big.  If you animate heavy objects slowly all the time, they’ll just look like they’re moving underwater.

In contrast, small characters take less time to accelerate and decelerate.

Head Acting

The classic head turn has a character arcing their head under (Illusion of Life example).  This is not necessarily true, it’s not always like that.  As your head rotates side to side there is a natural tilt that occurs with your head at the end of the action; this could be the reason the arcing under simplification.  Point is you don’t always have to arc under - it might come across as artificial (espec. if it is done too much).

Another common action is to have the point of the head lead the head turn (a more exaggerated version of the head arcing under).  Not sure if he’s seen too many people actually do this (unless for comic effect).  Believes it came out of the characters in the 30’s and 40’s (like the dwarfs in Snow White) where the character’s heads were so large, like giant flour sacks, that those head arcing shorthands seemed to work nicely.

The angle of the head denotes the character’s attitude.

Why do characters tilt their heads?  Most often seen when a character is asked a question.  Subconsciously the character is trying to a different view, one different from the one they had when originally asked.  Change of head angle = change to a new idea.

Pay attention to the timing of the head tilt.

(James videotaped someone in the audience shaking their head violently, then stepped through the filmed action)

The follow-through on the cheeks happened on the frame directly after the key.  Why?  Because the cheeks are so small and so closely attached to the skull.

Expressions

Two books you must read: Illusion of Life by Frank Thomas and Ollie Johnston and The Animator’s Survival Kit by Richard Williams.  James rereads the Illusion of Life occasionally.  With each read it’s interesting how he understands what they are talking about a little more.  Illusion of Life is more like animation philosophy than a guide.  Williams’ book is more of a step-by step technical guide (with about 90 pages on walks!)

Facial Unity

Freddie Moore’s influence where the eyes, eyebrows, eyelids, etc. all radiate from one central location (more of a visual note).  All elements are joined together and affect one another - a connection between the mouth and eyes.  There is a graphic rhythm to a facial expression.

Be careful to not always accent the eyes in time with the mouth movement unless it is a big shape.  If you always do it, the eyes will always look like they’re twitching.

Tremendous change of shape in the eyes when they look around.  There is a rotating of the eyelids with the eyeball.

(James videotaped himself looking all over the place in a severe close-up.  Clear that eyes do not retain a singular shape)

Eye direction always means something - Up and out often means the character is looking for an answer, searching for something.  When a character lies they almost always looking down.  But there are exceptions to the rule, a character could look down as they search for an answer.  Just be conscious of why and where the eyes are.

Dialogue

Time to dispel the 2 frames earlier myth

1st up - listen for accents within the dialogue - figure out the rhythm (the ups and downs of the jaw).

In a word like “beginning” with beGINning being where the accent is, James would often do an open mouth on the accent, then back closed, then slightly open again for the last part of the word and then back - like a seesaw.  Found in CG that it worked more effectively to simply pause slightly on the way back closed - so that you have little “ski slopes” in your curve editor.

2 frames earlier rule is basically a misunderstanding of how mouth shapes are formed.

Live action is always perfectly in sync - why shouldn’t animation?  The impulse to shift the animation comes when animating explosive shapes like Bs, Ps, and Ms or mouth shapes that involve the tongue like T, C, and K.  They look off-sync if you don’t shift and that’s because of the confusion into what really makes those sounds.

Dialogue is an action.

An M mouth and a P mouth and B mouth are not closed mouth shapes as described in popular animation books (like Preston Blair) - those are the mouth shapes that happen BEFORE the sound is heard; the preparation for the mouth shape.  B is an action.  You don’t hear the B sound until the mouth pops open.  T is not the sound your mouth makes when your tongue touches the roof of your mouth (again as illustrated in some books).  The T sound occurs when your tongue relaxes off of the top of your mouth.

Knowing this will help you become more intelligent about the mouth shapes you choose while animating.

We only have 24ths of a second (at least for now) so when in doubt, have it fall a frame earlier.

The idea that the reason the 2 frame shift works is because light travels faster than sound is ridiculous.  If that were true you’d want to have the sound come earlier (the mouth shape would then fall 3 to 4 frames after the modulation).

In the end it’s all about the preparation for the mouth shapes.  If you prepare them early enough, you’ll be in a good place.  Mouth begins to construct sentences long before a sound is even uttered.  You can have 8 or 10 frames where the character is forming a mouth shape, even before they’ve started talking.

Example from Terminator 2 with the T-1000 spilling into the helicopter.  He says “Get Out” but it looks like “Met Oww” - no preparation for the G and no follow through on the jaw for the T at the end.

Wary of lip-sync libraries as they’re might be a mouth shape that is only using a control for 1 or 2 frames.  It’ll look like it pops on.  His old methodology was to figure out the jaw ups and downs first.  Then go back in and hand-sculpt mouth shapes irregardless of the jaw keys - that way the two work in and out of each other in a more naturalistic way.

A lip-sync library helps ensure that a character stays on model but mouth shapes should be a very personal thing - should come from the animator.

Mechanics

Everything is based around the bouncing ball.  Easy to forget how important that basic concept is.  Bouncing balls are everywhere: gravity, inertia, impact, etc.  The classic image of a bouncing ball basically describe what you’d see on a curve editor.

It’s an easy concept to screw up.

Objects accelerate at 32 ft. per second per second (James didn’t make this up, apparently it’s real).

Hard to illustrate without drawing but here it goes (where A is a measure of 32 feet):

Second 1: A
Second 2: (A+A)+A (object falls the distance it has already fallen plus a new one, this repeats…)
Second 3: ((A+A+A)+(A+A+A))+A
Second 4: ((A+A+A+A+A+A+A)+(A+A+A+A+A+A+A))+A (and so on)

(I think I got that right.  It should describe a parabola.

Once you leave the ground you are a bouncing ball.  Nothing is going to stop you unless something hits you or pushes on you.  Until that counter-force occurs you will complete that parabola.  Can’t change direction midway in air.

Takes approximately 1/2 a second for an object to fall from head to toe (due to gravity).

(James videotaped someone dropping a tennis ball - took 17 frames (out of 30/second))

Everything falls at the same speed - bowling ball or tennis ball doesn’t matter.  This had never made sense to me until James explained how it was explained to him - think of the bowling ball as really 6 or 7 tennis balls all mashed together.  Gravity wants to act on all of them the same way - unless the object is so light that air gets in the way.  At this point he showed an image depicting where gravity is the strongest on Earth.  Objects in the Andes mountains will fall faster than those in the Hudson Bay - all because of how dense and bulgy the planet is at those spots.  And it doesn’t necessarily mean things fall faster in the mountains - more dependent on the depth of the crust.  James likes to research where a film takes place and apply those rates of gravity to the characters he animates (just kidding about that last part).

Inertia

Everyone’s favorite animation principle!

Inertia joins together all the animation concepts of drag, follow-though, slow-ins and slow-outs.  Explained in Newton’s Laws of Motions:

• 1. Bodies in physical states of motion want to continue in motion while those at rest wish to remain at rest.

This is why, when a character comes to a stop, the end of their clothing (like a robe or a jacket) will continue moving.  Until it reaches that point where it crashes into the character or where it reaches its furthest possible length, it will continue moving along at the same speed - until another force acts on it.

• 2. Acceleration is equivalent to the force acting on it.  More force, greater acceleration.  F=Ma (Force = Mass*acceleration)

If you have a big force and a tiny mass the acceleration will be huge.  If you have a tiny force on a large mass you’ll have a tiny acceleration.

• 3. Each action has an opposite and equal reaction.

This one is not as important for animators.  In the real world the actions are spread out into so many things that you don’t really have to pay all that much attention to it.

In a walk the up and downs are not as sharp because the knees and legs lessen the impact (instead of bouncing ball type path - smoother on the contact).

You use your muscles to retain balance all the time - foot placement is most important.  Your feet land within 1/2 an inch of where they should be to keep your body in balance - but you never really think about it.  Happens automatically.

Often your foot will move far forward of the body right before a direction change happens.

Relationship between the feet and where the body is over the feet is paramount!

Starting and Stopping

Stomach tightens just enough to get the shoulders over your feet; gravity does the rest.  It’s a subtle switch that happens before the first step even happens.

Stopping - last step is always an over-stride because of the inertia one has to counter-react.  That last contact angle of the body has the character leaning back.  Again body angle relating to foot placement is most important. 

When starting a run, have to kick your feet out to get body out of balance quickly.  In a run you have to lean really far back to come to a stop.

In a run, the head is directly over the foot when a plant is made (showed clips of Carl Lewis long jumping).  This keeps a character moving forward.  Strides are so large because you need to get your foot up and forward far enough so that when it comes down and strikes the ground it is moving at its highest velocity.

In a radical change of direction, as in a long jump, the step right before the jump will have the character throwing their foot way out in front to transfer the direction of energy from forward to up.

The head and arms and chest weigh enough to be able to be used as weights to help propel the body (like carrying around 20-30 lb. weights).  Often used to rotate and counter-rotate (showed footage of gymnasts).  Use the extremity’s to change the center of gravity.

Center of Gravity

The center of gravity is the point at which you could rotate the body around if the pose was still - not necessarily the center of the body.  Depending on the action could be in front of or behind the torso.  If you wanted to not think about it you could just move the pivot point for the body forward and back (in 3D).  Probably not a very functional idea, but conceptually it’s the same idea.

Example of a pencil bouncing off a table top.  If the angle is just right it will jump up instead of simply flying forward.

When running fast the ups and downs are minimized; the driving force is trying to keep everything moving forward.  The center of gravity remains relatively straight while the weight of the chest and hands drives the rotation.

Feet need to be placed far enough out of place to change direction or slow down. (Example of a long jump)  The center of gravity is always on that parabola.  The down comes right before the last step (on the 2nd to last).  Last step helps propel the body up.

Walking in a Circle

Point your toes so you have a big enough window from which to rotate.  Characters know subconsciously where they are going and will compensate by twisting the feet in enough to allow the body rotation to happen naturally and in balance.  That foot placement has to last for the entire rotation.

You tend to pivot on the balls of your feet and it only happens when your weight is not on that foot.

You can pivot on the heel (rarely) also when no weight is on it.  Same action as in preparing for a turn.

Planning

When planning out a character beginning to walk choose foot placement wisely; If the character needs to move quickly set the foot placement in such a way that the character can get off balance quickly.

Helpful technique can be to figure out foot placement in reverse (if there is a certain pose you are trying to hit somewhere down the line).  It’s something you should plan out from the beginning so that you can hit the right pose you are looking for.  Helpful to put target poses in. (Showed example from William’s book of the guy picking the chalk off the ground and writing on a board).

Ricochet Actions

Everything has a counteraction to everything else.

In a punch the hand has so much weight forward that it will pull the shoulder muscle out.  If it is violent enough the head will turn and the shoulders will come back or twist.  The force ricochets throughout the entire body. Actions don’t just happen on their own - disconnected from the rest of the body.

Difference between vigorously shaking an open hand or a closed one - open hands the body doesn’t move at all, but a closed fist will bring the shoulder and body along with it.  Open floppy hand shaking has hardly any follow through at all in the body.

You don’t overlap a lot in the wrists when gesturing.  Pointed out familiar shorthand technique of cartoon acting where the wrists will break - “floppy hands.”  The hands aren’t heavy enough to warrant this kind of uncontrollable action.  Wrist and hand work together.

Overlap

Usually has to be animated straight-ahead.  Recognizes that most of this is accomplished by simulations now in CG - but you might want to go in there and tweak it yourself.

In 2D, the primary action often had to be broken down on 2s or 4s in order to effectively predict where the object will be.

Remember what the object overlapping is made of - will help determine the rate of acceleration and deceleration.  Stiff whip will overlap differently from a feather.

Cloth is less stiff at the ends of a garment - those points will move more than those at the top.  There is less stuff to get in the way at the bottom as well.

Usually dynamics like this are done at the end.

Pay attention to the shapes created to make it flow into a better shape, thinking of where you have been and where you want to go.

Miscellaneous

Dance is edited movement.

In dance there are no real inbetweens.  There are extremes where things change direction, but every frame is important.  Not to say you have to key every single frame in a scene.

Easy to see that characters are not just torso, arms and legs.  The chest can collapse, rotate in, etc.

The shoulder structure starts close in towards the center of the body; shoulders just aren’t these things sitting on the edge of the torso.  Knowing this will help believability.

Fingers start at the wrist not at the start of the palm.  Hand works as one giant unit.

When walking a dog (where the dog walks you), you’re trying to compensate for this force pulling on you, which is why it doesn’t work very well.

Conclusion

Remember that even though you’ve been working on the film for a year, it is the first time your character is doing this action. (Example of Moses touching the “hot” stick in The Prince of Egypt - had to make sure that it seemed like Moses was doing this for the first time, even though it took days to animate).