Adobe Flash CS4 Professional How-Tos: 100 Essential Techniques

Chapter SixCreating Tweened Animation

Thanks to a process called tweening, not all animation has to be drawn frame by frame. If you give Flash two keyframes—one showing the way an object looks at the start of a sequence, and the other showing what it looks like at the end—Flash can compare the keyframes, analyze the differences between them, and gradually change one to the other by generating a series of in-between frames.

There are two kinds of tweens: shape and motion. Both types accomplish similar tasks, but they are suited to different types of objects: Shape tweens are used to animate editable paths; motion tweens are used primarily to animate instances of symbols. You’ll be grateful for the amount of time you save when you ...