The examples in this chapter demonstrated how powerful focus and depth of field can be as three-dimensional cues in a scene. In the first section, you designed a magnifying lens that illustrated how focus can be used to pull an image forward. You used a prerendered Gaussian Blur to simulate a lack of focus.
In the second section, we described how to move an object toward the plane of focus. We presented a couple of different techniques: a manual approach and a programmatic version. With the manual approach, you animated by hand a UFO that emerges from distance and then disappears into the sky. You then used two variations of the programmatic approach to guide spheres in an elliptical path on a checkerboard and make text dance in an elegant preloading animation. In these examples, we showed how to simulate a blur in Flash using multiple instances of a movie clip.
In the final section you explored some more advanced techniques and learned how the plane of focus itself can be changed and used to travel through a scene along the imaginary z-axis.
This chapter emphasized how focus, opacity, and blurring techniques can be used together to create a variety of effects that establish depth and help move an animated element to and from a plane of focus. These techniques are powerful tools that help add dimensionality and realism to a scene.