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Preface

Traditional Animation methods approach animation from a Timing point of view, which makes a lot of sense because animation is a sequence of drawings changing over time. I always felt traditional methods for constructing an animation left me with a few questions unanswered. I have been keeping notes on my own approaches as they make their way into my workflow and mindset. As the workflow has developed, I found that I was looking at animation in a different way: to forget about timing and concentrate on weight only. I found that timing can be easily applied to drawings afterwards, provided they were the right drawings. Once I fully committed to this mindset, everything clicked into place for me. I could forget about timing completely while concentrating fully on making the drawings, Poses and Weight right. I’ve also found that it could be applied equally to all scenarios; action, acting, walks, etc equally. Now, I know the traditional approach to be the best approach for the majority of people - and it’s proven, but I also expect there to be some people out there who’s brains are wired a bit like mine, and to them, I hope this approach proves useful.

Summary:

The weight based approach is the idea that each action comprises a sequence of weight shifts, and each shift has a beginning, middle and end. In traditional terms, the middle would closely resemble an Extreme, and the beginning and end would be Breakdowns. This approach defines where these Breakdowns should be and how they should look, or as I will call them, Beginnings and Ends. Because the Beginning, Middle and End will be defined exactly, these Key drawings can be made in sequence (straight-through) or with multiple passes. This approach has also somewhat been developed out necessity, due to the fact that I animate on a computer using Part-Time IK (IK Pose Manipulation, but FK animation).

What are Poses?

A Pose is the shape of the body at the Beginning, Middle and End of a weight shift. In order for us to create these Poses there are 3 fundamental points of reference we will need:

• The Weighting Point
• The Leading Point
• The Attention Point

The Weighting Point

There is only one point on which a (two-legged) character bears the most of their weight. While other points will bear some of the weight - we are looking for the one that bears most. This is true for both characters in motion and still characters. The lesser weight bearing points are considered only in terms of balance.

There are of course exceptions. At one important instance in time, the weight can be shared exactly equally between two points - but this will ONLY be for an instant when weight is in the process of being transferred from one point to another - it should be remembered this point in time is never held, and it will not last more than one frame.

And we have another exception when no points bear weight - in the Middle of a jumping action, for example.

The Leading Point

The Leading Point is usually a joint on the body that drives the character’s conscious action, i.e. the action they are thinking about. For example a character pointing the finger: The Leading Point will be anywhere from the shoulder to the finger tip. How far ‘out’ the Leading Point will be on the arm will depend on the amount of conviction the action is performed with.

The Attention Point

Usually this is simply where the character’s eyes are focussed, but not always. It can be a very strong story-telling tool to have the character’s Attention Point in a place where they are trying very hard not to look.

Weaving the 3 Points into a Pose

Good Poses will incorporate all 3 points in a way that the whole character’s body-shape will accentuate the 3 Points.

It is common to think of a ‘line of weight’ and a ‘line of action’… we’ll also add a ‘line of attention’.

Line of Weight

The Line of Weight Originates in our Weighting Point, and moves up through the Body’s joints (ankle, knee, hip, spine, etc.).

A sketch line which is drawn through these points will form a smooth and simple curve, slightly ‘C’ or ‘S’ shaped.

The Line of Action

The Line of Action will originate in the Leading Point and move out through adjacent joints in a way that will complement or contrast the Line of Weight.

The Line of Attention

The Line of Attention will originate at the Attention Point and move back through the Posed Body shape, again in a way the will contrast or compliment the other Lines.

Some examples

Let’s look at an example: This is the cover shot for Pixar’s Boundin’ (cover shots for animations are usually very easy to read these lines from).

Looking at the Sheep’s Line of Weight we can see it leads nicely into his Line of Attention. We can see how smooth and simple the curves are. Except one - the line that falls from the Sheep’s Leading Point - it’s a bit wobbly for such a short line. This is because his action doesn’t yet have much conviction (also written all over his face). And he is leading from the knee rather than the foot, so the rest of the leg dangles. The Line of Action going back to his Body is shown going up through his Spine to compliment the Line of Weight, but another could be shown going across’s the Hips and down the weighted leg, both lines contrasting and complimenting the Line of Weight.

Of course the Jackalope’s attention is on the Sheep’s Leading Point. His Lines of Action and Attention would be very similar because he is holding his position and his only conscious act is to watch the sheep’s leg. I’ve also shown a balance point and line in the dotted red going from his elbow back through his spine because it supports the large curve going through his right hip. Yet more lines could be added along the top of the rock, through the Jackalope’s elbows and shoulders and even in the framing of the sheep’s elbows and ‘hand’ hooves - everything leading to the Leading Point in this shot.

One last thing worth noticing is that the Sheep’s knee is also the only element of this shot that falls on Thirds. But of course, it’s easy to find patterns in anything if you look long enough…

So How do we put this into our Animation?

Now we have some nice tools to help us produce good Poses, and we sit down to put together an animation based on an action we have in mind… but the first question that always pops up is: “Where do I start???”.

In order to produce animation reliably and efficiently, there is a tried and tested procedural approach to do exactly this. The procedure is called Blocking or Blocking Out.

Blocking

Blocking is the process of picking the right Poses to draw that will define boundaries and reference points for our animation. Blocking provides the whole structure for our animation.

If we think of a child drawing a house. They will always begin with a square - this is their structure. Once the square is in place it gets easier to add details like the windows, doors, roof etc. Without the structure they would fail to draw something that would normally be easy.

In the same way Blocking provides the structure for animation. It is important that the structure we build is as good as we can get. In fact, a well structured piece of animation can stand on its own without adding detail. But the inverse isn’t true, lots of great details without structure wouldn’t work.

The Blocking Process

We have many approaches to Blocking, this Weight Based approach is primarily concerned with the following 2 Steps, or Passes:

• The Posing Pass
• The Forces Pass

In The Posing Pass we draw Poses that describe how the character’s Weight is being held or transferred for each action. It will concern the position, weight and balance of every part of the whole body. It will also express the character’s subconscious attitude.

The Forces Pass shows how the Leading Point effects the rest of the body. We have already put it in place during the Posing Pass - now we have show how the adjacent body parts react to the forces generated by the Leading Point. This will usually only concern one or two limbs, parts or appendages - but in some extreme cases can have effects rippling through all parts of the Body.

There are many fundamental differences between the 2 Passes, so here’s a few comparisons:

• The Posing Pass
• This forms the STRUCTURE
• This concerns the WHOLE Body shape
• This shows WHAT the character does
• This Pass can stand alone
• The Pass expresses the character’s subconscious attitude

• The Forces Pass
• This forms part of the DETAIL
• This concerns only some LIMBS
• This shows HOW the character does it
• This Pass can’t exist alone
• The Pass gives more expression to the character’s conscious action

As the Posing Pass is the really important part of animation, we’ll concentrate there for the rest of this post.

Drawing the Poses

Every action is made up of a sequence of weight shifts. Every weight shift is made of three Key Poses: a Beginning, Middle and End.

To determine the position and Pose of the 3 Key Poses, it can be easier, at first, to find the Middle Pose. The Middle Pose is often the same as an Extreme in usual terminology.

The Middle Pose

The Middle Pose is the point in time where the Weighting Point is taking more weight than at any other time during the Action. It will also happily coincide with hand-gestures, facial expressions, and everything else that the character is showing.

For example, if the character points at something with their finger: the finger and arm will be at their most out-stretched at the same time that the ball of the foot is taking most weight. Or if our character slumps into dejection - the head and shoulder will be at their lowest points when the heel takes most weight (not counting for reactions to forces yet, which have their own Pass).

Or if a character is looking left and then right - this is 2 Extremes (while it would be possible to turn a head from left to right without having any weight-shift, it is also very unnatural).

Or if a Character has one hand extended out an up to the left above their head in a kind of 70’s dancing Pose, and then switches to a mirrored type Pose with the opposite hand - this can require 4 Middle Poses, as the Weighting Point can transfer from Left Heel to Left Ball to Right Ball to Right Heel through the course of the action.

The weight shifts are more obvious if we act them out for ourselves, and it takes some time to get tuned to listening to your body - to feel which part is taking weight. At the same time, one should be careful to carry out the actions at normal speed, and not slo-mo, because this can ‘contaminate’ the true weight shifts.

Now we are starting to see a difference between Traditional ‘Extremes’ and Weight Based ‘Middles’. In the last example we would normally have drawn only 2 Extreme Poses: Pointing Left and Pointing Right. The other weight-shifts would have been left as Breakdowns, and they would not have any clear requirements of how they needed to be drawn or what they might look like - already leaving things to guesswork, trial and error. But now we know exactly when they should appear - when the Balls are taking most weight. And when we consider the Weighting Point and Line of Weight, we will be able to decide how they should look.

Remember these extra Middles are not replacements for Breakdowns, they are still Extremes - just extra ones, so lets qualify the equivalent of Breakdowns…

Beginnings and Ends

Every Action needs a Beginning, Middle and End, we’ve already talked about Middles, so lets look at Beginnings and Ends.

There are some very obvious Beginning and Ends, and when talking about Walks, they even have their own great names already - Contacts. Lets take an even more obvious example: A typewrite key being pressed. The Beginning is the precise moment when the finger comes into contact with the key, the Middle is where most pressure is being applied and the key is down, the End is the precise moment where contact is just about to be broken.

Unfortunately not all Beginnings and Ends are as obvious as to have their own Contacts, but once we know the Middles that we will need, we can simply wrap them with Beginnings and Ends on either side.

If this is sounding like it going to become a lot of Poses, here’s some good news: the End of one weight shift, will be exactly coincident with the Beginning of the next. This is the exact point of Weight-Transfer when two points bear the weight of the Body equally. Remember this is only an instance in time and can never be held, it only lasts for one Frame.

Should the End/Beginning or moment of transfer happen halfway between Middles?

No, generally Beginnings cover a longer distance when getting to Middles and Ends cover short distances. How much distance is drawn between Beginning and Middle or Middle and End is hugely important as this defines how smooth or snappy the action will be. Or how much ‘lead-in’ and ‘follow-through’ through we want.

Conclusions

Now that we have the complete structure built for our animation, we can add timing as frame intervals between the Key Poses and details as reactions to Forces.

Since the structure is built on a procedural approach this should also facilitate a more predictable experience when timing out actions in a pencil-shooter (or similar), and thereby speed up the timing-for-animation learning curve.

To see how this process is applied in IK Boost, please see the Animation Workflow post.

Finally, please feel free to leave comments, questions and thoughts