Wired Movies and Sprites

Sprite Animation

Sprite animation differs substantially from traditional video animation. With traditional video animation, you describe a frame by specifying the color of each pixel. By contrast, with sprite animation, you describe a frame by specifying which sprites appear at various locations. At a given moment a sprite displays a single image selected from a pool of images shared by all of the sprites.

You can think of a sprite animation as a theatrical play. In a QuickTime movie, the sprite track bounds are the stage; in an application, a sprite world is the stage. The background is the play's set; the background may be a single solid color, an image, or a combination of images. The sprites are the actors in the play.

A sprite has properties that describe its location and appearance at a given point in time. During the course of an animation, you modify a sprite's properties to cause it to change its appearance and move around the set or stage.

Each sprite has a corresponding image. During the animation, you can change a sprite's image. For example, you can assign a series of images to a sprite in succession to perform cell-based animation.