In order to make a shape tween, we'll have to create another shape on another keyframe. Click on step 2 to see how that's done.
Flash Animation 2: Shape Tweening
From Adrien-Luc Sanders, former About.com Guide
With this lesson, we'll pick up at the end of where we left off in Lesson 1, Motion Tweening. We ended in frame 12, after one second of animation that moved our circle from one corner of the canvas to another; now we're going to animate the circle morphing into another shape using a technique called shape tweening. Shape tweening can take two different shapes at keyframes set any number of frames apart, and mathematically calculate the frames in between to produce a smooth animation depicting the transformation between one and the other.
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