Flash 8 Cookbook

4.4. Applying Advanced Tweening Effects

Problem

You want to apply an advanced tween that combines several easing settings and/or has elastic or rebound effects.

Solution

Use the Custom Ease In/Ease Out utility.

Discussion

Prior to Flash 8, applying advanced tweens was a manual procedure requiring you to use several tweens back to back. For example, if you wanted to do something as simple as animate a ball that drops and bounces, it required several tweens—one as the ball dropped and accelerated, a second as the ball rebounded, a third as gravity pulled the ball downward again, and so forth until the ball finally rested. The process became even more complex if the ball’s shape changed as it hit the surface, as a tennis ball might.

However, starting with Flash 8, you can accomplish such advanced and custom tweening effects with just one tween by utilizing the Custom Ease In/Ease Out utility. In order to use the utility, you must first apply a tween as discussed in Recipe 4.1. Then, with the first frame of the tween selected, click the Edit button next to the Ease field in the Property inspector. Clicking the Edit button opens the Custom Ease In/Ease Out utility.

The Custom Ease In/Ease Out utility displays the tween progress as a line moving across a graph from the lower-left corner to the upper-right corner. The lower-left corner represents the starting point of the tween, and the upper-right corner represents the stopping point of the tween. When you first apply a custom tween effect using ...