Introduction
Disney’s twelve basic principles of animation were introduced by the Disney animators Ollie Johnston and Frank Thomas in their 1981 book The Illusion of Life: Disney Animation.
Principles
- Squash and stretch 挤压和拉伸
This is the principle that animated objects will get longer or flatter to emphasize their speed, momentum动力, weight, and mass.
It can be applied to simple objects, like a bouncing ball, or more complex constructions, like the musculature of a human face. Taken to an extreme, a figure stretched or squashed to an exaggerated degree can have a comical effect.
In realistic animation, however, the most important aspect of this principle is that an object’s volume does not change when squashed or stretched. If the length of a ball is stretched vertically, its width (in three dimensions, also its depth) needs to contract correspondingly horizontally.
The ball doesn’t have to be stretching the entire time that’s falling. Don’t overdo squash and stretch“.
2.Anticipation预备动作
Anticipation is used to prepare the audience for an action, and to make the action appear more realistic.
The technique can also be used for less physical actions, such as a character looking off-screen to anticipate someone’s arrival, or attention focusing on an object that a character is about to pick up.
Taking anticipation of step further, you can actually have multiple levels of anticipation.
- Staging演出布局
Staging is the presentation of any idea so that it’s completely and unmistakably clear.
This principle is akin类似的 to staging, as it is known in theatre and film. Its purpose is to direct the audience’s attention, and make it clear what is of greatest importance in a scene.
This is a very broad principle because it covers so many areas of animation, such as acting, timing, camera Angle and position and setting.
The essence of this principle is keeping focus on what is relevant, and avoiding unnecessary detail.
It should also have proper timing. Let one action finish before the other person starts their action instead of overlapping them.
Sometimes you need to insert pauses if there’s something on the screen that needs to be processed by the viewer before moving on.
Sometimes if there’s any text on the screen. You should keep it on screen for as long as it takes to read it out loud three times.
- Straight ahead action and pose to pose 连贯动作法与关键动作法/逐张画法和原动画法
These are two different approaches to the drawing process.
- Straight ahead action scenes are animated frame by frame from beginning to end.
“Straight ahead action” creates a more fluid, dynamic illusion of movement, and is better for producing realistic or unpredictable action sequences, such as fire, water particles, clouds of dust, explosions.
The reason why straight ahead works well is because there are laws of physics that work at a constant rate, and it’s hard to predict how it will work post a pose.
However, it is hard to maintain proportions and to create exact（but doesn’t in computer animation）, convincing poses along the way.
B． “Pose to pose” involves starting with drawing a few key frames, and then filling in the intervals later.
“Pose to pose” works better for dramatic or emotional scenes, where composition and relation to the surroundings are of greater importance. A combination of the two techniques is often used.
There is some vocabulary that goes into it.
Key关键张: Main poses
Extremes极端张（原画）: Secondary poses
Breakdowns细分张（小原画）: further broken-down poses.
Make the keys first. Perfect them. Then decide the farthest the character will go in each direction using extremes. And then decide how you want the extremes to connect using breakdown poses. At this point you can start in-betweeing中间画.
- Follow through and overlapping action跟随动作与重叠动作
That is a technique of having body parts and appendages附件dragged behind the rest of the body and continue to move when the body stops.把身体的各部位及附加物与身体分开的技术，在身体运动停止时继续运动。
Follow through: the way parts of the body continue to move after the body is stopped.身体静止后身体部件（由于惯性）还在继续运动。
Overlapping action: the offset between the timing of the main body and its other parts.主体和他的其他部件的时间错开（产生重叠效果）。
Drag: the technique of delaying the movement of body parts in relation to the main body.延迟身体各部位跟主体之间运动的技巧。
Basically, when the main body moves, the tip of the appendage should be the last to catch up. And when the body stops, the tip should follow through the farthest before settling back.
The amount of drag that you give something says something about its mass.
The “moving hold” animates between two very similar positions, even characters sitting still, or hardly moving, can display some sort of movement, such as breathing, or very slightly changing position. This prevents the drawing from becoming “dead”.
- Slow in and slow out 缓入缓出
The movement of objects in the real world, such as the human body, animals, vehicles, etc. needs time to accelerate and slow down. For this reason, more pictures are drawn near the beginning and end of an action, creating a slow in and slow out effect in order to achieve more realistic movements.
This concept emphasizes the object’s extreme poses. Inversely, fewer pictures are drawn within the middle of the animation to emphasize faster action. This principle applies to characters moving between two extreme poses, such as sitting down and standing up, but also for inanimate, moving objects, like the bouncing ball in the above illustration.
With 3D animation and motion graphics, adding slow in and slow out as a matter of changing the motion curves from linear to spline by adjusting the Bezier handles.
- Arc 弧线运动
Most natural action tends to follow an arched trajectory, and animation should adhere to this principle by following implied “arcs” for greater realism. This technique can be applied to a moving limb by rotating a joint, or a thrown object moving along a parabolic trajectory抛物线轨迹. The exception is mechanical movement, which typically moves in straight lines.
- Secondary action 附属动作
Gesture that support the main action to add more dimension to the character animation.
Secondary action is not Overlapping Action.
Adding secondary actions to the main action gives a scene more life, and can help to support the main action. A person walking can simultaneously swing their arms or keep them in their pockets, speak or whistle, or express emotions through facial expressions. The important thing about secondary actions is that they emphasize, rather than take attention away from the main action.
- Timing 时间控制
The personality and nature of an animation is greatly affected by the number of frames inserted between each main action.
- Exaggeration夸张
Exaggeration is an effect especially useful for animation, as animated motions that strive力求for a perfect imitation of reality can look static静态and dull.
If a scene contains several elements, there should be a balance in how those elements are exaggerated in relation to each other, to avoid confusing or overawing the viewer.
When motions are quick. The exaggeration needs to be bigger in order to be noticed. In order to boost its presence you can either make it stay on the screen longer.
A good rule to foolow is to push the exaggeration level until it actually becomes too much. Then wind it back until you’re satisfied with it.
- Solid drawing 扎实绘图
The principle of solid drawing means taking into account forms in three-dimensional space, or giving them volume and weight.确保提及看上去像再有体积，重量，和平衡的三维空间中。
The animator needs to be a skilled artist and has to understand the basics of three-dimensional shapes, anatomy解剖, weight, balance, light and shadow, etc.
How to drawing solidly:
- Draw a figure from all angles.
- A straight line instantly makes the circle look flat.
- Avoid making parallel lines. Lines should be bent towards to the vanishing point.
- When doing a rough pass of the character, use basic solid shapes like spheres, cubes and cylinders.
- Draw perspective lines on the ground.
- Use overlap as many as possible.
- When doing lines is to avoid symmetry, avoid “twinning”.
- Appeal 吸引力
Basically characters that you animate should be somewhat pleasing to look at. They should have some kind of charismatic超凡魅力 aspect to like about them.
Giving character a dynamic design can greatly boost its appeal:
- Variety of shapes. 使用大量形状
- Proportions. 玩转比例
- Keep it simple. 最简原则
Conclusion
While originally intended to apply to traditional, hand-drawn animation, the principles still have great relevance for today’s more prevalent computer animation.
related link:
https://www.bilibili.com/video/BV1cx411x7y8/?spm_id_from=333.788.videocard.10