FOLLOW THROUGH & OVERLAPPING: 2D Animation principle

17 December, 2008

FOLLOW THROUGH & OVERLAPPING: 2D Animation principle

When you animate a character,
you will notice certain things. Especially while a character moves, every thing
does not start and stop at the same time. Primary action begins first, secondary
action reacts to it. Primary action stops, secondary action stops after some
time. So it is best advised to follow the primary action, animate secondary
action on a separate layer as it follows a different timing and spacing.


Just as a golfer’s
follow-through communicates the result of the swing, the transition from one
action to the next is important in communicating the relationship between the
actions. Actions rarely come to a sudden and complete stop. So, too,
follow-through and overlapping actions allow you to establish the flow of the
character’s motion. You can typically implement this by varying the speed at
which different parts of a body move, allowing movement beyond the primary
aspect of the motion. For example, the fingers of a hand typically follow the
movement of the wrist in a hand gesture. This principle also emphasizes that
actions should not come to a complete stop, but smoothly blends into other

Follow-through and
overlapping action
are two techniques that help make the action richer and
fuller with detail and subtlety. Follow-through action consists of the reactions
of the character after an action, and it usually lets audiences know how he or
she feels about what has just happened or is about to happen. In overlapping
action multiple motions influence, blend, and overlap the position of the
character. In three-dimensional computer animation a lot of the common
follow-through motions of clothing and hair, for example, can be animated with
dynamics simulations. The layers and channels in three-dimensional computer
animation software allow us to mix and blend different overlapping motions from
different areas of the character.

When the main body of the
character stops all other parts continue to catch up to the main mass of the
character, such as arms, long hair, clothing, coat tails or a dress, floppy ears
or a long tail (these follow the path of action). Nothing stops all at once.
This is follow-through. Overlapping action is when the character changes
direction while his clothes or hair continues forward. The character is going in
a new direction, to be followed, a number of frames later, by his clothes in the
new direction. “DRAG,” in animation, for example, would be when Goofy starts to
run, but his head, ears, upper body, and clothes do not keep up with his legs.
In features, this type of action is done more subtly.

Example: When Snow White
starts to dance, her dress does not begin to move with her immediately but
catches up a few frames later. Long hair and animal tail will also be handled in
the same manner. Timing becomes critical to the effectiveness of drag and the
overlapping action.

Follow Through: While
anticipation is the preparation of an action, follow through is the termination
of an action. Actions rarely come to a sudden and complete stop, but are
generally carried past their termination point. Follow-through is what happens
to an object when it goes from a state of motion to a state of rest, and
conversely from rest to motion. The effect of acceleration and deceleration can
be seen in the way that the energy of motion affects the object and its
disparate parts when it moves from one state to the other.

Initiation: In figure
movement, actions of the parts are not simultaneous, some parts initiate moves,
while others follow. For example, the wrist leads the hand and fingers in a


Weight and Drag:
Appendages or loose parts of a character or object will drag behind the leading
part of the object. Then as the object comes to a stop, the looser parts
continue to move taking longer to settle down and stop. Weight of the appendages
dictates the speed with which they follow the lead, heavier objects drag farther
behind. The lighter the object the smaller the drag and the quicker the stop.

Overlapping Action is another of the
cornerstones of animation. By overlapping the actions of a characters’ body,
hair, tail, clothing, etc. your animation will feel more fluid and life-like. In
life, everything moves at different speeds and at different times. Overlapping
action is a tool used by animators to emphasize the action and mood of the
character. When a character moves across the screen some parts of the body move
before or at different rates than others. Some parts of the body will lead the
action and some parts will follow the main action.

When animating a scene begin with the main action
and then add the overlapping and secondary actions. From a practical standpoint,
one of basic elements of overlapping action is
the use of “S” curves when something changes direction.


Overlapping actions occur when
elements begin, arrive or stop at different times. All actions move with their
own arcs. That includes: body parts, hair, tails, clothes, etc. When animating a
scene begins with the main part of the action there add the secondary and
overlapping actions.

Overlapping action is usually a
good idea in animation to have a time lag between the movements of different
parts of the figure. This is called overlapping action. In a slow gentle action
this may not be necessary, but in a more violent movement it helps to give
fluidity. If several characters are dancing in unison on the screen, that is,
using the same animation traced off several times, their movements look much
more alive and fluid with an overlap of one or two frames on some of the
characters. The result is that these characters are just out of sync with the
others, which appears less mechanical than having them exactly in unison.
Trained soldiers marching when the effect should be rather machine-like should
of course be timed exactly together. For a squad of new recruits, however, a
four-frame overlap on some of them may not be enough to give a ragged look to
their marching.

Imagine a dog running along and
coming to a stop. The first things to stop are probably his front feet, then his
back legs and feet come up behind. As he has gone into a ‘squash’ onto the front
feet at first, once all four feet are firmly on the ground he comes out of this
and might even go up too high and settle back into the final pose. If he has
floppy ears, these are probably the last things to come to rest.

The principle, on which
overlapping action is based, is really only that of momentum, inertia and action
through a flexible joint. The reason it works so well in animation is that the
natural tendencies of movement work in this way and these are picked up and
exaggerated. An object’s functional parts move at different rates during
acceleration and deceleration, depending on their individual place in the
physical structure of the whole. This is why you will see that the beginning
motion of a leg will overlap the middle portion of the motion of an arm, which
will overlap the forward movement of the hair, and so on. The ability to see and
understand the phenomenon of follow-through and overlapping action is critical
to creating the illusion of movement.

The overlapping and
follow-through of the secondary objects depends on:

  1. Its own weight.
  2. Its degree of flexibility.
  3. Its reaction to air

The path of action that
secondary objects follow will be different from that of primary one, but is
determined by primary object.

Five categories of Follow
Through and Overlapping Action:

Appendages: The first
category is very easy to see in real life and applies to any appendages, long
hair, a big overcoat, or a tail. Anything that is loose or hanging from the
figure that is doing the action will continue to move even after the figure has
stopped. It’s important to pay special attention to the timing of appendages to
create the right feeling of weight, because if the timing is off it could very
well make your animation look worse rather than better. It is also very
important to make sure that the appendages follow through on the same path that
the figure was moving in. if you do not you will end up with a very unnatural

Body Parts: The entire
body never actually moves all at once. In stead it moves different parts at a
time. While the torso of the body may have already reached its destination the
arm might still be in motion. Everything is twisting, turning moving ahead, and
trying to keep up. In order to portray your characters attitude correctly the
chest, head and shoulders may stop all together. Since this is the part that
portrays the characters emotion and the part that the audience should see. Then
a few frames later the rest of the body parts start to settle into their final
position, but not all at the same time. When the whole figure has come to a
complete stop in a definite attitude, this is called a held drawing.

You should use held drawings to
show a characters feelings and emotions. When a character is in full motion it’s
difficult to portray emotion but when the drawing has come to a brief halt you
want to maximize the opportunity to portray the way he feels.

Loose Flesh: The loose
flesh on a figure will typically move at slower speeds than the skeletal parts
of the body.  For example when a person moves their head their cheeks, lips and
ears will trail behind the more solid head. The action of trailing behind the
main figure is called drag and it gives a looseness and solidity to the figure
that is vital to the portrayal if life. When this technique is done well it
should be hardly detectible. You are drawing pictures the way they would look at
that exact moment, and are not designed to be seen by themselves but in sequence
with all the other pictures.

The Ending: Many times
an action goes by so fast that you can’t really portray much about a character
with that action. Instead you have to portray the character immediately before
and or after an action is taken.

Example: A golfer takes
a mighty swing which covers only a few frames, but what happens afterwards can
easily take five feet of film and is much more revealing, whether he is graceful
and slick in his follow through or wraps himself up in a knot.

The anticipation sets up the
action we expect (or is it the action the character expects?), the action
whizzes past and now we come to the punch line of the gag, the follow through,
which tells us what happened and how it all turned out. The ending of every
action should always be considered part of the action. It should never be enough
to simply reach the action and then quit, if you do this your animation will be
short choppy and not nearly as entertaining as it could be.

Moving Hold: When a
character needs to stand still for a while to portray a feeling or emotion it’s
tempting to draw one careful drawing of the main pose and then just hold that
pose without movement for a few extra frames. While this is definitely the
easiest way to go, it really isn’t the best way to go. The problem is that when
a drawing is held motionless for that long it breaks the flow of action, the
illusion of dimension will be lost, and the drawing will begin to look flat. The
best way to hold a drawing and yet still keep it moving is to make two drawings,
both with all the key elements of the post but one slightly more extreme than
the other.

Tags: , , , , , , ,

Leave a Reply

Your email address will not be published. Required fields are marked *