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4. Squash and stretch

Animation variables (avars) control object movement, like stretching and squashing a ball. Squash and stretch is a key principle in animation because it communicates an object's material to the audience and brings the object to life. Animators don't just move things, they make them seem alive, like a hopping ball instead of a simple bounce!

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Video transcript

- Now that you get the basic idea, let's have a little fun with it. We'll start by adding another control. At Pixar we call these "animation variables" or "avars" for short. This avar scales the ball out in X, and down in Y. You can control the timing of this avar using the same graph editor. Now we can make the ball stretch on the way down, and squash when it hits the ground. This idea of squash and stretch is one of the key principles of animation. Animating the squash and stretch of an object helps us to communicate what that material is made out of. Remember, our job as animators isn't just to move things around, it's to bring them to life. And one way to do that is to show the character's thought process. If this ball is alive, then maybe it's not just bouncing, maybe it's hopping. And before it hops it'll squash itself down in anticipation, just like Luxo Jr squashes himself down before taking a hop. This is some of the real magic of animation, is that we can take something that's fundamentally a lifeless object, and bring it to life. (electronic squeaking) (lampshade rattling) (metallic whining) (metallic sighing) (wooden thudding) (wooden thudding) What kind of ball do you want to animate? What's it doing? What's it thinking? Can you bring it to life?