Adobe Flash CS4 Professional for Windows and Macintosh: Visual QuickStart Guide

277

Animation

with Motion

Tweening

11

In a classic tween, you create animation

by setting up a series of keyframes; each

keyframe contains a separate instance of the

symbol you want to animate. You manipu-

late each symbol individually to change its

properties. Flash calculates any di erences

in the symbols’ properties at each keyframe

(position, size, rotation, and so on) and uses

that information to create a series of images

in which the symbol changes incrementally.

Motion tweens work somewhat di erently.

You set up a single keyframe, with a single

symbol instance, then de ne a motion-tween

span. Within that span property keyframes

account ...