Basic Methods of Flash Animation

In Flash, there are three basic methods of animation:

• Frame-by-frame animation is achieved by manually changing the individual contents of each of any number of successive keyframes.

• Tweened animation is achieved by defining the contents of the start and end points of an animation (with keyframes) and allowing Flash to interpolate the contents of the frames in between. There are two kinds of tweening in Flash:

  • Shape tweening

  • Motion tweening

• Timeline Effects were introduced in Flash MX 2004. Timeline Effects give you "automated" animation and visual effects that you can apply to shapes or symbols. Timeline Effects are created by prebuilt scripts that you can control by choosing settings in a preview dialog box before the Effect is rendered. After you choose settings and apply an Effect, Flash generates Graphic symbols and adds a new layer to the Timeline to hold the frames needed to display the Effect. You don't even have to make any keyframes!

Advanced Flash developers tend to animate almost exclusively by controlling Movie Clips with ActionScript. Although this might seem intimidating to illustrators or animators who are more comfortable using analog tools, this programmatic approach to creating motion (and even artwork) dynamically makes sense. After all, computer animation is the art of orches-trating items according to various properties over time — and in the digital realm numbers describe all properties, even color. The Timeline Effects feature is a big step toward making this type of authoring more accessible. Coders now have an easy way to distribute or reuse scripted animation and effects, and designers can take advantage of these without having to learn how to write or edit advanced ActionScript.

Cross-Reference 

Although the methods for authoring custom Timeline Effects are beyond the scope of this book, we describe the basic process for adding and using a custom Timeline Effect in Chapter 12, "Applying Filters and Effects." In a quick tutorial in the same chapter, we'll show you how to install and use Samuel Wan's "Jitter" Effect. The Timeline Effects that ship with Flash are only the beginning.

Flash components and Timeline Effects make it easier than ever for beginning programmers to integrate ActionScripted elements into Flash projects. But, before you jump into scripted animation, it helps to know how to animate on the Main Timeline with simple groups and graphics.