Shape tweening allows us to change the shape of objects over time. This is similar to morphing where one object changes to another. One of the main differences between a shape tween and a motion tween is that shape tweens do not work with symbols or groups. If you want to apply shape tweens to groups or symbols, you have to first ungroup or break them apart.

In our first tutorial we will create a simple shape tweening. We are going to turn a star into a circle using a basic shape tweening.

1. Create a new FLA

2. Select the first frame on the main timeline and in the properties panel assign a shape tweening to that frame (Fig1)

Fig1
3. with the first frame still selected, select the polystar tool . Click on the options button in the properties panel and select star for the style, 5 for number of sides and 0.50 for star point size. (Fig2)

Fig2

You should end up with a star that should look like the one below (Fig3)

Be sure that the object drawing option is NOT selected when you draw the star and the circle on the stage. If it is selected your shape will automatically be converted in a symbol and the shape tweening won't work. If those shapes have been converted into symbols just break them apart by selecting them and pressing CTRL+B



4. Insert a blank key frame at frame 30, your timeline should now look like the one below (Fig4)



You will notice that all frames that are associated with a shape tween are light green. All frames associated with a motion tween are light blue.

5. With keyframe 30 selected draw a circle on the stage, this will represents the final state of our morphing. (Fig5)

Fig5

We now have a star on frame 1 and a circle on frame 30 that are both linked with a shape tweening (Fig6)

Fig6

If you test your movie you should end up with an animation like the one shown below :