Arc – The Seventh Principle | Principles Of Animation
ARC – In this topic, we will now discuss and learn the seventh principle of the 12 principles of animation, the arc.
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The 12 principles were introduced by Ollie Johnston and Frank Thomas, both of which are Disney animators who wrote this in their book called The Illusion of Life: Disney.
The seventh principle, as I mentioned in an overall implies that most natural actions follow an arched trajectory. In other words, objects follow a semi-circular or curved motion in order to make the action more realistic.
By definition, it is a part of the circumference of a circle or other curve.
With this principle, according to AnimationMentor, like any of the principles, it is one of the vital tools to make the animation realistic and graceful. Otherwise, a broken one would make the movement less believable.
The seventh principle usually applies to natural movement, in terms of circular ones. For rigid movements like a robotic arm, linear arcs are usually used.
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The seventh principle may be applied to the weight and direction of an object.
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For weight, when it is heavy, the movement tends to move inwardly in contrast to light ones, in which they move outwardly.
Here is a simplified video of the seventh principle, again by Alan Becker, the creator of the famous “Animator vs Animation” series.
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