Flash 8 Cookbook

4.6. Looping Animations

Problem

You want to create an animation, or a portion of an animation, that loops indefinitely.

Solution

Embed the animation in a movie clip symbol.

Discussion

Unless you use ActionScript to tell it otherwise, every timeline begins playback as soon as it is loaded and plays through the timeline at the document frame rate until it reaches the end. After it plays the last frame, it loops back to the beginning and plays all over again. In other words, looping animations is Flash’s default behavior, and all you need to do to create one is to create any animation and export the .swf file.

But you may find that you need to loop portions of an animation, while other portions are not looped, or not looped as often. Imagine a cartoon in which a character is chased across a background; the camera follows the character, who remains in the center of the screen while the background scrolls by. Several animated elements may be in play, such as the following:

• A 5-frame loop depicting the legs while the character is running

• A 5-frame animation of the arms swinging wildly

• A single-frame graphic of the torso

• A 5-frame looping animation of the head turning back and forth

• A 10-frame loop of a distant bird’s wings flapping

• A 50-frame loop of the background

Because the animation comprises elements that loop and others that don’t, and because the loops are of different lengths, the animator cannot rely on the overall looping behavior of the main timeline. Each loop needs to animate independently ...