Inertia

One of the key terms used in the field of animation is “weight”. It is one of the biggest things that the animator must consider in any shot he or she works on. However I would say that we should be a bit more specific about what we mean by the word.

I started thinking about this when watching ‘Avatar’ before Christmas. There was a shot at the start of the film where soldiers wake up from hypersleep and float around in zero gravity. Now the film on the whole was very well made in my opinion, but I thought this one shot was frankly awful. The reason? The characters’ weight was off. I believe they did that shot with some kind of rig holding the actors up, but I have seen many instances of the same problem in animation.

I really think that animators should maybe think more in terms of inertia. It takes a certain amount of force to get any object moving, to stop it moving, or to change its direction. The more massive the object, the more effort is required to affect it. This is a principle that is universal and independent of things like gravity. Weight on the other hand is a consequence of gravity. If you remove the gravity, you create a weightless object, but this does not mean you can ignore all you have learned. The object has the same mass as it had with gravity and so has inertia and requires forces to move it around.

Practically speaking, it is fine to think in terms of weight or mass or sausages, or whatever you want. Just don’t forget that you need to think carefully about these things ALL of the time. In Avatar, just like with many films, it felt like they forgot this.

Weight In Walks

When walking, people have to propel themselves forward somehow. It seems to me that there are three ways in which people do this.

1) The use of body weight. The person leans forward, the weight of their torso giving forward momentum. This is how we come to think of walking as ‘controlled falling’. These people often take short steps, having to catch their body frequently.

2) The use of arm weight. The person swings their arms in large arcs, the weight of the arm forcing the body forward.

3) The use of leg weight. The person puts plenty of force behind their legs as they swing them forward, propelling the body along. These people often (but not always) lean further back in their walk, possibly to maintain balance.

Different combinations of these attributes produce different kinds of walk.

Power Walk

On occasions I have notes that could really do with some examples to illustrate them. However I’m pretty pushed for time and might not have chance to do said examples. This is one such occasion I’m afraid! Hopefully when I have a little more time available, I’ll go back and add some.

If you read ‘The Animator’s Survival Kit’ by Richard Williams, you will see that in his standard walk, the arms swing to their greatest extent on the ‘down’ position. I wanted to animate a person walking along purposefully the other day and happened across a quick and easy way to do it.

All you do is….

1) have the upper arms at the greatest part of their swing on the down position, as per Richard’s book.

2) Rather than having the forearms drag behind the upper arms, have them precede them. Have the forearms at the greatest part of their swing on the contact positions. You can do the same with the hands for extra effect.

Of course this effect can be added to with leaning the upper torso forward and so on, but the arms along will make a more purposeful walk.

Again, apologies for the lack of an animated example, but I just don’t have time to do one at the moment.

Extremes and Breakdowns

Just a little tip for today. When creating an extreme or a breakdown, always keep in mind the next extreme that you haven’t yet drawn or posed. Hopefully you have done a bit of planning before starting, so you should know roughly what the next pose will be. Keeping it in mind will guide you in creating the previous pose, so the positions of all the body parts will be more appropriate for the movement.

See? I told you it was small!

The Second Purpose of Anticipation

All animators are accustomed to using anticipation to help sell the following action, for example a character crouching down before springing up into the air. However anticipation can have another use than to prepare the audience. It can fool the audience.

Using anticipation, one can encourage the viewer to think that a corresponding action is about to happen. However there is no reason why that action has to happen. Why not do something different to surprise them? Here’s an example from Richard Williams….

Composition of Ideas

I notice a common mistake is to have too much going on in a shot at once. Imagine a shot with two characters in it.

Now if these two characters are doing independent things, it becomes too much to show both at the same time. The viewer’s eye doesn’t know where to look. It is much better to present one character first, followed by the other. This can be done by showing one character and then zooming, tracking or cutting to a view involving the second character.

Now what many people seem to like doing in animation is to do a ‘Hot Shots’ style shot where something is happening in the foreground focus point of the shot, with something hilarious happening in the background. In such a case, it would spoil the gag to show the background joke and then track out to the person or people in the foreground. However there is one vital point that so many people seem to miss. The thing going on in the foreground MUST NOT be important.

Too often an important story point is missed because the audience is busy looking at the background joke. No matter how funny the joke, it just isn’t worth the loss of a story point. In ‘Hot Shots’, these scenes always worked because the foreground event was of no real significance to the plot of the film.

Materials

When animating anything, whether living or inanimate, always consider what material it is made from. I forget this from time to time, most recently in animating a scene for Lego Harry Potter, which unfortunately I can’t put on here yet. The scene involved harry flying on a broomstick. I made the tail of the broom flop around wildly, forgetting that a real broom consisting of sticks would not behave like this.

The problem is further confused in my case by the fact that I am animating Lego – a plastic toy. Does a Lego broom behave like it is made of sticks, or like it is made of plastic? This is the kind of question I try to consider as much as possible.